Tested: Bontrager SE4/SE5 Tyres

Traction galore!
Traction galore!

Going from some mediocre tyres to something that does exactly what you’re after will drastically increase the performance of your bike for a relatively small amount of cash.

Over the last few years, we’ve been impressed with the development of Bontrager’s range of tyres, so we were excited to get some trail time in on their new SE4 and SE5 offerings.

Bontrager's SE line is more aggressive than the XR range we've rated highly in the past.
The SE5 is one heavy duty tyre.

Who are Bontrager’s SE4 and SE5 tyres for?

Bontrager’s SE4 and SE5 tyres are a step up from Bontrager’s well-renowned XR trail tyre range, pitched as offerings for the all-mountain rider or enduro racer.

The SE4 tyre shares the same tread pattern as Bontrager’s most aggressive trail tyre, the XR4, but with a sturdier casing and stiffer sidewall for increased puncture protection and cornering stability.

The SE4 strikes a burly profile mounted to our set of Praxis Works C32 Mountain Wheels.
The SE4 strikes a burly profile mounted to a set of Praxis Works C32 Mountain Wheels.

The SE5 is a toned-down version of Bontrager’s G5 downhill tyre; however, it has slightly more puncture protection than the SE4.

The SE5 is Bontrager's sturdiest non-downhill tyre.
The SE5 is Bontrager’s sturdiest non-downhill tyre.

Due to the SE4 coming in a 2.4” width and the SE5 tyre only being available in a 2.3” width, and with the SE5 featuring increased puncture protection, we ran an SE4 on the front paired with an SE5 on the rear for the majority our testing.


How do they hook up?                                                     

Bloody well! The SE4 and SE5 tyres excel in rocky and loose conditions, but due to the wild shifts in weather Sydney has been experiencing recently, we’ve been able to test these tyres in all sorts of conditions, from bone dry and dusty, to drivetrain destructing slop.

In dry conditions, the grip from both tyres is very predictable, and the rolling resistance feels better than comparable rubber from other tyre brand alternatives with similar tread and casing.

The rolling resistance of the SE4/5 is exceptional.
The rolling resistance of the SE4/SE5 tyres is exceptional.

The SE5 is exceptionally stable under braking as a rear tyre, as well as shedding mud and other gunk when the trails are wet, however, we think Bontrager should produce a 2.5” version. The larger 2.5″ size would be a great tyre to have on the front of an enduro bike as a dependable all-rounder for all but the wettest conditions.

The SE5 only comes in a 2.3" width, which we think is a real shame.
The SE5 only comes in a 2.3″ width, which we think is a real shame.

It was only when it was very wet that we found the limits of the SE4 on the front, with the tread clogging up, and the side knobs not providing enough penetration to give the predictable handling we experienced in dry to medium conditions.

This isn’t unexpected, though, as, for a tyre that’s grippy in most conditions with such great rolling resistance, you can’t really expect it to double as a standout wet weather performer.


Do they wear out quickly? 

The SE4 and SE5 tyres do use a fairly soft rubber compound, especially on the side knobs. We chewed through a set in a solid long weekend of lift assisted gravity riding, but most tyres won’t survive multiple days of chairlift aided abuse on chopped out trails.

The wear rate on the SE4 and SE5 is about what you'd expect considering the rubber compounds used.
The wear rate on the SE4 and SE5 is about what you’d expect considering the tackiness of the rubber.

In terms of how fast the SE4 and SE5 wear from normal riding week to week, we would say it’s not drastically different to how quickly comparable tyres from Maxxis or Schwalbe will wear- for example, a 3C tyre from Maxxis or a Vertstar tyre from Schwalbe.


Do they puncture? 

Whilst the SE line of tyres from Bontrager does feature more puncture protection in the form of beefier sidewalls and casings to their XR line, we still had two punctures in the rear whilst running pressures in the high twenties, and on one occasion with the Huck Norris Anti-Flat Tubeless Protection System.

We experienced two punctures with the SE5 on the rear, including one with the Huck Norris installed.
We experienced two punctures with the SE5 on the rear, including one with the Huck Norris installed.

In comparison to other tyres on the market, the only other non-downhill tyre we’ve used that’s been 100 percent reliable throughout testing has been Maxxis’ Double Down offerings, however, they do weigh in around 100 grams heavier than the Bontrager SE models for a comparable size.

We experienced no punctures testing Maxxis' Double Down range.
We experienced no punctures testing Maxxis’ Double Down range.

We should disclose that these punctures occurred barging through rocks on less than ideal lines, so overall we were impressed with the SE4’s and SE5’s durability, especially considering their lighter weight than other ‘enduro’ focused tyres on the market.


What if I’m not happy with them?

One thing about Bontrager tyres we think is truly exceptional is their 30-day unconditional guarantee. Whilst we’ve been impressed with the SE4 and SE5 in a variety of conditions, if you pick some up and you’re not happy, you can return them to your Bontrager dealer within 30 days for a product replacement or full refund.

We're big fans of Bontrager's unconditional guarantee.
We’re big fans of Bontrager’s unconditional guarantee.

If you’re on the fence about trying these tyres out, you’ve really got nothing to lose.


Verdict?

Bontrager’s SE4 and SE5 offerings are well worth a look if you’re an aggressive rider or enduro racer looking for a tyre that’s dependable in a variety of conditions, but doesn’t weigh a ton. Our biggest gripe is the single width available for both tyres, as we think a 2.5” SE5 matched with a 2.3” SE4 on the rear could be an excellent combination.

Tested: Mitas Kratos Tubeless Supra Tyres

Tread for bite.

So much of what makes a good set of tyres comes down to tread pattern and profile. The Kratos in 2.45″ width is on the more aggressive spectrum of all-mountain tyres, but this doesn’t mean it doesn’t roll AND rail at the same time. The fairly close centre knobs do a great job of finding a happy medium between rolling resistance, braking performance and durability – sitting comfortably between say, a Maxxis Minion SS and a Schwalbe Nobby Nic. The mid and outer knobs then are spaced far further part and in a far more aggressive shape, giving superb grip on a range of surfaces. We found the outer knobs really clever; close pairs of knobs spaced out between each other still lets the rails roll smoother, but under pressure digs in deep. This eliminates that sensation you may get from big-knobbed tyres on off-camber rock slabs where riding on the side knobs suddenly feels like a set of stairs (well, not that bumpy but you get the idea).mitas-kratos-1070909

Mitas, despite having a fairly small range of models, show almost no weakness in their line-up. The Kratos is designed as a versatile second in command to its more aggressive counterpart, the Highlander. Despite the difference in size, these two tyres complement each other incredibly well.

Read our review of the Highlander here.

Could we use as a combo?

Not only do they have similar aggressive patterns and amazing side rails, but they work great as a front-back weight-saving combo – the compromise in knobs for rolling resistance in the rear doesn’t mean a lack of cornering or braking grip. You also won’t have to worry about having a ‘weaker’ rear tyre either – with the same innovative TEXTRA casing as the Highlander.mitas-kratos-1070919

TEXTRA sidewalls

TEXTRA is Mitas’ premium sidewalls – a compound of ultra-tough rubberised fabric weaved into the layers of rubber, which greatly improves the tyre’s slash resistance without adding extra plies of rubber and weight. This allows the sidewalls to still retain the perfect, supple feel and performance of a 127TPI casing and not over-stiffen them.mitas-kratos-1070926

Mitas really back their TEXTRA casings, so much in fact that they offer a 100-day sidewall guarantee! That’s a lot of riding time; if you haven’t cut them within 100 days, that’s a pretty solid indicator of a great tyre. If you do in normal riding conditions? Mitas have you covered.

Compounds

A cracking tread pattern isn’t anything without a dialled rubber compound, right? The TEXTRA model of Kratos comes with their Mitas’s Enduro Trail Dual Compound rubber. The centre tread is their CRX (Carbon Race Extremely light) Compound –aA low-density rubber compound infused with what they call carbon graphite, which is said to enhance the abrasion resistance without compromising on grip, and increasing its strength. The side knobs are a softer compound, the same as found on the Mitas Highlander we reviewed. 

We found the tread blocks to feel soft enough to not slide off hardpack or slick rock, yet not too soft that the wheels felt slow to roll. A good indication that the different compounds are doing their thing, playing to their strength of being softer and harder where needed.mitas-kratos-1070939

We had the most expensive CRX compound tyre with the TEXTRA sidewalls to test, but for a lower price you can also get two other compounds without the (T)extra protection – the Grey Line and Standard compounds. The Grey Line is a mix of their harder CRX compound for the base and centre while utilising a softer compound on the side knobs. This has been a long-standing feature on Mitas’ former tyres under the ‘Rubena’ banner – with their signature grey side knobs. This gives you the best of both worlds for grip in corners and high rolling resistance and low tyre wear.

If you are a do-it all rider that needs some extra meat in the front end for light trail riding, a great pair of all mountain rubbers, or a fast-rolling rear end to supercharge your enduro bike, have a serious look at these tyres. Tubeless ready and super easy to seat on your wheels, comprehensive sidewall protection and superior feel, as well as a well thought out tread pattern for the all-round rider, the Kratos is a tyre we will be keeping in the stable for quite a while.

Flow’s First Bite: E*Thirteen TRS+ 650 Tyres

Wide rims and the reduced tyre pressures tubeless tyres can be run at go together like strawberries and cream.
Wide rims and tubeless tyres with lower pressures go together like strawberries and cream.

E*Thirteen’s first foray into the tyre market, the TRS range incorporates a number of exciting features that draw upon recent advances in wheel and tyre technologies.

What is the E*Thirteen TRS?


There are two versions of the TRS tyre, the TRS Race and the TRS Plus. We’ll be testing the TRS Plus, which uses slightly harder rubber compounds than the Race, however out of the box the compound feels very soft, similar to Maxxis’ 3C tyres, which is impressive considering this is the entry level tyre in the range. The Plus retails for $99.95, and the Race retails for 114.95, and both tyres are available in 27.5″ and 29″ options.

The profile could be described as sitting somewhere between Schwalbe's Magic Mary and a Maxxis Minion DHR II.
The profile could be described as sitting somewhere between Schwalbe’s Magic Mary and a Maxxis Minion DHR II.

The tyre profile is aggressive, with wide knob spacing, but the profiling of the centre knobs is quite low, and the compound of the centre tread is slightly firmer, which should assist in decreasing rolling resistance.

In the pivotal cornering department, the TRS uses meaty, angled knobs. The knobs have additional support at the base, which should assist in preventing knobs from collapsing or tearing during hard cornering. The compound of the cornering knobs is very soft, so it will be interesting to assess the TRS’s durability throughout testing.

The TRS is designed to work with 24-31mm internal rim widths, and the shape looks excellent on SRAM Roam wheels with a 30mm internal rim width.
The TRS is designed to work with 24-31mm internal rim widths, and the shape looks excellent on SRAM Roam wheels with a 30mm internal rim width.

Will they work with my rims if they have wide internal widths?


Due to the advent of wider internal rim widths, E*Thirteen designed the TRS range to work specifically with 24-31mm internals. The test wheelset they are currently mounted to is a SRAM Roam wheelset boasting a 30mm internal rim width, and the tyre profile looks spot on.

How heavy are they?


In terms of weight, the TRS Plus comes in at a very respectable 870 grams. Considering the aggressive tread pattern and reinforced sidewalls, and that an alternative like a 2.3 Maxxis Minion DHF in the comparable Double Down sidewall protection comes in at over 1000 grams, we’re impressed. It will be interesting to see if the lighter weight comes at the cost of puncture protection considering the style of riding these tyres are aimed at.

The weight of the E*Thirteen TRS Plus is very respectable.
The weight of the E*Thirteen TRS Plus is very respectable.

Where would you use this tyre?


The open spacing of the TRS and tall cornering knobs will provide excellent traction in a variety of trail conditions. We will be running the tyre front and rear, however if you were to pair this tyre we would recommend using it as a front tyre with something faster rolling out back.

How will E*Thirteen's first tyre offerings fare against the known tyre brands?
How will E*Thirteen’s first tyre offerings fare against the known tyre brands?

Our first impressions of the TRS Plus are positive, so we’re excited to see how they perform out on the trail.

www.e13components.com.au

Flow’s First Bite: Mitas Highlander Tyres

What’s the deal with them then? And where’s the grey tread colours of yester-year gone!?

Here’s a quick look at what has us so eager to blow some berms and blast some turns on our enduro bike right now!

mitas-highlander-1070065

Beefy Tread Pattern

The tell-tale sign of a good downhill tyre is a no-nonsense, aggressive and openly spaced tread pattern with a meaty shape and 2.45″ width. The Highlander is not dissimilar to other tyres in its class, but has a more symmetric and uniformly angled pattern than most – which is claimed give the Highlander better grip in mud and softer soils.mitas-highlander-1070122

Enduro Trail Dual Compound

Mitas’ dual compound configuration provides a simple and effective solution to the problem of decent tire wear vs traction performance; a harder, more wear resistant rubber makes up the base and centre knobs of the tread, while a softer, slower rebound compound is used on the side knobs.

mitas-highlander-1070135

DH SUPRA MAXX & TEXTRA

WHY THE YELLING? Don’t be put off by more buzzwords – these tyres pack an impressive construction in the form of 4ply sidewalls embedded with a rubberised fabric to try and eliminate any chance of cuts or flats. What is even more impressive, is that each tyre weighs in at 1000 grams each – almost exactly the same as comparable 2 and 3 ply offerings from Maxxis.

The Textra models in the Mitas tyre range are backed by a 100 day sidewall guarantee, that’s what we call confidence!

mitas-highlander-1070115 mitas-highlander-1070107

Along with its $90 price tag, sidewall guarantee and cool unique graphics, the Mitas Highlanders are enticing enough to raise the eyebrows of even the deepest of Maxxis fans. We are looking forward to putting this tread through every kind of trail torture in the coming weeks.

Maxxis High Roller II / Minion SS Tyre Combo

What have we got here?

The High Roller II and Minion SS are two popular treads from Maxxis. As the name implies, this is the second generation of High Roller. The Minion was the downhill tyre that was a serious ‘must-have’ for a number of years (cheers to Sam Hill for cementing its popularity), and the SS is a semi-slick version of the tread. It scores the same cornering knobs as the regular Minion DHF, just shaved down in the middle.

Compounds and construction details?

Maxxis Tyres-4597
3C = triple compound. EXO = reinforced sidewall.

EXO is Maxxis’s lightweight sidewall reinforcement. 3C stands for triple compound, naturally. It’s soft on the sides (42a durometer), firmer in the centre and firmer still underneath, for good rolling speed and excellent grip. The Minion SS is dual compound, not 3C, which is why it’s a little cheaper too.

 How do the weights and prices stack up?

Pretty well. Maxxis tend to be good value, and at $64.95 for the Minion SS and $79.95 for the High Roller II, they’re much cheaper than an equivalent from Schwalbe, and in line with what you’d pay for a Specialized or Bontrager tyre.  Weights are quite reasonable, 850g for the High Roller and 773g for the Minion SS.

These tyres have found a home on our Giant Trance.
These tyres have found a home on our Giant Trance.

What bike did you fit these to?

Our Maxxis High Roller II / Minion SS combo has found a home on our Giant Trance test sled (the same bike we’ve been using to review Shimano’s SLX groupset).

This bike is going to play host to plenty of test parts, so we want a set of reliable tyres that are up to the job – we don’t want to be worrying about flats when we’re trying to concentrate on the performance of other products.

Maxxis Tyres-4591

Will they fit my wheels?

Yes, you can get both of these tyres in 26, 27.5 and 29” versions. The Minion SS is 2.30” only, while the High Roller II comes in 2.30” plus 2.40” in the 27.5”diameter.

Mixing and matching:

On paper, these tyres looked like the perfect combo for this bike – we wanted something fast and whippy out back, to get a little loose, but with bite we could trust up front.

Mixing and matching tyres is nothing new, and we do it a lot. Other grippy front / rippy rear  combos that we’re very fond of include the Schwalbe Rock Razor/Hans Dampf, the Specialized Slaughter/Butcher and the Bontrager XR3/XR4.

Maxxis Tyres-4600

How have they gone?

They’re quick! We hoped these would roll well, but they’ve surpassed expectations in that regard. At the same time, they’re great in the corners, in a wide range of trail conditions. The High Roller excels on hardpack and or slightly sandy corners, or in the loamy stuff too. In fact, it’s an awesome all-rounder. For such a speedy tyre it handles hard braking brilliantly, which is good because the Minion SS does not.

Not cuts, flats, tubeless leaks or other worries have arisen either, and Maxxis are traditionally rather indestructible.

Maxxis Tyres-4588

Any drawbacks?

For a 2.30” they feel a little skinny. Maybe it’s just the relatively narrow Shimano XT rims they’re mounted to, but Schwalbes and Bontragers in the ‘same’ size look a fair bit bigger. The smaller volume makes them less impressive in really wild conditions with lots of loose rock.

As you’d expect too, there’s not a huge amount of rear braking traction, so the line between braking and skidding is easy to overstep.

Maxxis Tyres-4593

Would we recommend them, and why?

100%. If you like the ride feel of a rear tyre that encourages a bit of fishtailing, but you still want the front end grip to stop you crashing onto your face, then this is a great combo. The value for money and reliable construction is just the icing on the performance cake. These tyres mightn’t be new in the market, but they still deliver.

Where can I get them? 

Maxxis tyres are available across Australia at a number of preferred dealers. Take a look below to find a dealer in your state.

Queensland: 

FOR THE RIDERS / (o7) 3891 7561 www.fortheriders.com.au

CRANK’D CYCLES PH / (07) 4728 5838 https://www.facebook.com/crankdcycles/?rf=790415367668940

New South Wales/ACT  

SUMMIT CYCLES / (02) 9661 4245 http://www.summitcycles.bike/

STEEL CITY CYCLES (02) 4267 1747 www.summitcycles.bike

FLOW BIKES  www.flowbikes.com.au

Victoria:

MY MOUNTAIN / (03) 9388 8678 http://www.mymountain.com.au/

LIFE OF BIKES / (03) 5940 2299 http://www.lifeofbikes.com.au/

Western Australia:

TBE / (08) 9277 9181 https://www.tbe.com.au/search.asp?mc=5&sc=951&b=25&slf=1

South Australia:

BICYCLE EXPRESS /(08) 8232 7277 http://www.bicycleexpress.com.au/

Northern Territory:

SPOKES NT  / (08) 8931 3111 http://spokesnt.com.au/

Tasmania:

SPRUNG / (03) 6334 5419 http://sprungmtb.com.au/

Fresh Product: Maxxis Double Down Tyres

Tubeless tyres have made the mood deflating hiss of a puncture a far less frequent occurrence. But with the emergence of incredibly capable mid-travel bikes, as well as enduro racing, a gap has emerged in the market for tyres that combine lightweight efficiency with the puncture protection required in more technical terrain and at higher speeds.

_LOW6416
Aside from the DD on the casing, there’s nothing to tell you there’s anything different about these tyres.

So what are Maxxis doing about it?


Maxxis’ Double Down casing sits between their EXO and Downhill casings, offering more puncture protection and a stiffer sidewall than an EXO casing with around a 100-gram weight penalty for an equivalent EXO tyre in the same width. We’ve fitted a set of Double Down Aggressors to our Canyon Strive long term test bike (http://flowmountainbike.com/tests/wheelworks-flite-wide-carbon/), and we’ve noticed a discernible difference in sidewall stiffness, which has allowed us to run them at lower pressures without burping air.

Maxxis Aggressor-7777

Is it available for every tyre?


No, not at moment – Maxxis are concentrating on the tyres that are really aimed at the Enduro market. Double Down casing is currently available in Minion DHF, Shorty, Aggressor, High Roller II, and Tomahawk tread patterns, giving riders a variety of options from fast rolling tyres (like the Aggressor or High Roller) to wet weather options (like the Shorty).

_LOW6522
The Aggressor is a new tread in the Maxxis lineup. With closely spaced knobs, it’s quite a fast tyre. Probably more of a rear tyre overall, but we’re giving it a go up front too.

Will they work for me?


If you’re the kind of rider who pinches or tears tubeless tyres, wallops rims, or just rides hard, then give these a try. 100g weight penalty at each wheel is not a big price to pay for more reliability.

We think the type of rider who would benefit from Double Down casing is likely to pair a more aggressive front tyre with something faster rolling out back (some bloke called Richie Rude runs a DHF up front paired with an Aggressor in the rear to moderate success).

Do they cost more?


Yes, a little. A Double Down tyre will set you back about $20 more than the equivalent ‘standard’ tyre – $99.95 is the going rate, versus $79.95 for an EXO 3C tyre.

Maxxis Minio WT-7858
Big boy. The Minion DHF WT 2.50.

Are they suitable for wide rims?


While the trend towards wider rims has huge benefits, a lot of tyres haven’t kept pace. A ‘standard’ tyre on a 35-40mm rim can end up with a very square profile that’s not conducive to consistent cornering.

Maxxis have got on the front foot here, and released ‘WT’ (Wide Trail) specific tyres for rims with 35mm or greater internal widths. We’ve got a Minion WT at Flow HQ awaiting testing as well. It’s a beast of a tyre, so keep your eyes peeled!

Maxxis Aggressor-7790

Where can I get them? 


Maxxis Double Down tyres are available across Australia at a number of preferred dealers. Take a look below to find a DD dealer in your state.

Queensland:

FOR THE RIDERS / (o7) 3891 7561 www.fortheriders.com.au

CRANK’D CYCLES PH / (07) 4728 5838 https://www.facebook.com/crankdcycles/?rf=790415367668940

New South Wales/ACT  

SUMMIT CYCLES / (02) 9661 4245 http://www.summitcycles.bike/

STEEL CITY CYCLES (02) 4267 1747 [email protected]

FLOW BIKES  www.flowbikes.com.au

Victoria:

MY MOUNTAIN / (03) 9388 8678 http://www.mymountain.com.au/

LIFE OF BIKES / (03) 5940 2299 http://www.lifeofbikes.com.au/

Western Australia:

TBE / (08) 9277 9181 https://www.tbe.com.au/search.asp?mc=5&sc=951&b=25&slf=1

South Australia:

BICYCLE EXPRESS /(08) 8232 7277 http://www.bicycleexpress.com.au/

Northern Territory:

SPOKES NT  / (08) 8931 3111 http://spokesnt.com.au/

Tasmania:

SPRUNG / (03) 6334 5419 http://sprungmtb.com.au/

Tested: Continental Pure Grip X-King and Mountain King Tyres

FLOW3321
818g in a 29×2.4″ size. The Mountain King is great mid-weight, loose conditions trail tyre.

We had two different tyres to review – the X-King and the Mountain King – and in both we opted for a 29×2.4″ size. The X-King is probably the one that most riders will reach for first, it fulfils that classic fast-rolling, trail tyre role, with low tread blocks that are closely spaced. The second tyre we had to test is the Mountain King, which is a unique looking tyre with lots of open space between the centre tread blocks, and staggered side knobs. It’s a more aggressive tread than the X-King, but it’s still aimed at the trail bike market.

FLOW3344
With low-profile tread blocks, the X-King is a fast mover. 802g in a 29×2.4″.

All the Pure Grip treads are tubeless ready tyre (which is exceptional at this price point) and we initially fitted them to two different bikes. After a few rides we decided that the X-King and Mountain King actually make a pretty mean combo, so we popped the X-King out back and the Mountain King up front on our Norco Optic C9.2 (read the bike review here!). Running a tyre combo that’s fast out back and bitey up front is something we often do, particularly if we’re riding on trails that don’t require a lot of hard rear braking.

If we lived where the trails were predominantly hard-packed, we’d go an X-King front and rear. Or if the trails tended to have a bit of loose rock, like Buller for instance, a pair of Mountain Kings would be killer. But for the varied conditions near us, mixing and matching worked well.

FLOW3338
We ran the X-King out back, and the more aggressive Mountain King up front on our Norco Optic.

29×2.4 might sound like a massive pair of tyres, but compared to most nominally sized 2.4-inch tyres, the Contis are on the narrow side. Busting out the vernier calipers revealed the Mountain King to be 57mm across, or 2.25-inches, when mounted to a set of Pacenti TL28 rims. Keep that in mind when you’re choosing your size – if your inclination is to go for a 2.2-inch, we’d encourage you to upsize to the 2.4.

If you are rough on rubber or live in a particularly slicey kind of area, perhaps the ProTection version is the way to go.

Most of our previous experience with Conti tyres has been on their ProTection series, which are little heavier and more expensive, but are indestructible. The Pure Grip range gets a lighter sidewall, and unfortunately we did put a small cut into our rear X-King tyre after slamming the sidewall into the edge of a sandstone block. Rider error? Certainly, but it still does prove to us that there’s a reason you pay more for the ProTection versions of this tyre. We wouldn’t say the Pure Grip tyres are fragile, but if you are rough on rubber or live in a particularly slicey kind of area, perhaps the ProTection version is the way to go.

FLOW3332
The open centre tread pattern does well in softer, looser soils. It’s not a big tread for a 2.4″ – it measures up closer to a 2.25″.

The combo of X-King and Mountain King is a winner. These tyres move quickly in a straight line, and thanks to the open, blocky design of the Mountain King there’s still plenty front end braking and cornering bite in loose soils. The fast-rolling X-King will break traction before the Mountain King too, which makes for some killer speedway style drifts with a dab of rear brake, if that’s your thing.

 A pair of these costs less than a single tyre from many of the competition, you’ve really got to give these a look in.

In terms of overall grip, the performance of these tyres is varied, and really depends on the trail surface. The compound is pretty firm, and so they don’t have that gummy adhesion to roots and rocks you experience with some other super soft tyres, especially in the wet. As you’d expect from the X-King’s tread pattern, it does best in hardpack or other fast surfaces, whereas the Mountain King prefers softer conditions that let it bite in hard. On hardpack the Mountain King is claws noisily at the trail, but it’s still quite confident as the side knobs are well supported and don’t ‘walk’ or squirm.

FLOW3348
The X-King is best on the rear if you ride loose conditions, or good front and back if your trails are more hardpacked.

The plus side of the firm compound is the durability of the tread blocks. After a bunch of rides in rocky terrain, the tyres have still got the little ‘hairs’ from the rubber moulds and we’ve only noticed minimal wear on the rear X-King tyre. Compared to the wear we’ve come to accept as normal from soft compound tyres, these guys look like they’ll last for ages.

Yes, there are plenty of tyres out there with compounds that provide more grip in more varied conditions, or which have tougher sidewalls. But when you consider that these are tubeless-ready, they come in a variety of tread patterns, and that a pair of these costs less than a single tyre from many of the competition, you’ve really got to give these a look in. All up, the Pure Grip range represents excellent value for money with options to suit most riders and trails. We think there’ll be a lot more Continental on the trails in the future.


Bargain: Pushy’s currently have these tyres on sale for $34.99. Take a look! 


 

Flow’s First Bite: Continental Pure Grip Tyres

The Mountain King is aimed at the dual-suspension trail bike market.
Conti position the Mountain King as an all-rounder for the dual-suspension trail bike market. We’re running it on a Norco Optic C9.2.

The Pure Grip range offers up Conti’s traditionally high-quality construction and compounds but at a seriously good price. We’ve seen them going for as low as $34.99 through some Australian online retails. That’s pretty hard to ignore, when you consider that it’s easy to pay up to three times that amount for tubeless rubber.

The tread pattern is rather unique, very open, allowing good penetration in loose surfaces.
The tread pattern is rather unique, very open, allowing good penetration in loose surfaces.

We’ve lined up two sets of Pure Grip tyres to review; the X-King and the Mountain King, both in a 29×2.4″ size. Both of these treads are available in a narrower 2.2″ width if that’s your thing (in both 29 and 27.5″ too), but we prefer the extra volume of the larger tyre.

Low-profile tread blocks on the X-King.
Low-profile tread blocks on the X-King.

The X-King is a tread we’ve used many times in the past. With closely spaced, low-profile knobs, spread evenly across the tread, it’s your classic fast-rolling trail tyre. We’re hoping that the speedy tread pattern combined with the large volume 2.4″ size, run low pressures, gives us that perfect combo of pace, grip and control. For a 2.4″ tread, the weight is reasonable, at 802g on our scales.

With a more open and blocky tread pattern, the Mountain King is aimed at looser riding surfaces or generally more aggressive riding too. The spacing of the tread blocks across the centre should deliver a lot of braking and climbing bite. Its side knobs are well supported, and far more pronounced than the X-King. We weighed the Mountain King at 818g, which is pretty good for an aggressive tyre like this.

The sidewalls are two-ply, with three layers under the tread.
The sidewalls are two-ply, with three layers under the tread.

Looking at the tyres’ features, perhaps most importantly, these are a proper tubeless-ready tyre with Conti’s Revolution Tubeless Ready bead. This alone makes these tyres exceptional at this price point, tubeless rubber for under $40 is pretty much unheard of.

The casings are quite lightweight. Most Continental tyres we’ve ridden in recent years have been the super-tough ProTection versions, which have some fairly heavy duty four-ply construction. These Pure Grip treads have three-ply construction under the tread area, and two-ply in the sidewalls. The lighter casings of the Pure Grip tyres save about 70-90g over the equivalent ProTection version, but hopefully they’re still resilient. Time will tell!

Closely spaced centre tread should keep the X-King rolling quickly, even in the 2.4" size.
Closely spaced centre tread should keep the X-King rolling quickly, even in the 2.4″ size.

Conti’s compounding technologies are some of the mot advanced in the business; their Black Chili compound has legions of devoted fans, who praise its balance durability and grip. The Pure Grip compound found on our test tyres, claim Conti, sits just below Black Chili in the performance stakes.

We’ve fitted these tyres to two very different 29ers – time to go find out if these treads can deliver premium performance at a bargain price.

 

Flow’s First Bite: Mitas Textra Tyres

_LOW0061
The sidewalls are reinforced with a rubberised fabric that is super cut resistant.

We’ve got mixed feelings about this, especially when it comes to tyres. While the feeling of zippiness and responsiveness that you get from lightweight tyres is nice, we’ve seen far too many rides and races ruined through fragile tyres getting sliced to pieces. Consequently, we’re usually happy to carry around a bit of extra heft for the security and reliability of tougher treads.

The Textra series of tyres aims to mitigate this compromise, with new sidewall technology which adds a lot of protection with minimal weight gain.

The new Mitas (formerly Rubena) Textra series of tyres aims to mitigate this compromise, with new sidewall technology which adds a lot of protection with minimal weight gain. We’ve been running a pair of these treads on our 29er for the past couple of months; out back we’ve had the zippy 2.25″ Scylla Textra, and up front the more knobbly Kratos, also in a 2.25″.

_LOW0063
The Scylla is a fast-rolling tread. In race conditions, we’d be tempted to use this tyre front and back.

Mitas (nee Rubena) tyres have a strong following in cross country racing circles, where they’ve won a stack of National Championship and been raced by Australian Olympians. The cross country heritage is clear when you pop them on the scales –  even with the Textra sidewalls, these are quite a lightweight set of treads, especially the Scylla which is just over 620g. The Kratos with its more aggressive tread blocks is still only 750g.

Mitas clearly have a lot of faith in the technology as they’re offering a 100-day sidewall guarantee on a Textra tyres!

The Textra sidewalls are these tyres’ real point of difference. The sidewalls are hatched with the pattern of an ultra-tough rubberised fabric which greatly improves the tyre’s resistance to slashes, but without making the sidewalls overly stiff or thick, which can affect the ride quality. This is the genius of the Textra tyres – greater protection, but preserving the supple performance of the 127TPI casing. In fact, to touch, the Textra sidewalls don’t feel noticeably thicker than a regular Mitas tyre. But Mitas clearly have a lot of faith in the technology as they’re offering a 100-day sidewall guarantee on a Textra tyres! You can do a lot of riding in 100 days, so that kind of reassurance is gold, as anyone who’s had to bin a near-new tyres with a slashed sidewall will attest. And apparently, this faith in their product’s performance is justified – the local Mitas distributors promise us they haven’t had one report of a slashed sidewall on a Textra tyre yet, and we certainly didn’t experience any issues. Taking a look at the wording of sidewall guarantee, it’s a very honest, no bull-shit assurance – if your Textra tyre gets slashed in normal riding conditions, you’re covered. You can read more here.

_LOW0054
The Kratos has a more open tread pattern for looser conditions and great braking bite, but still rolls well too.

We set our Mitas tyres up on some Stan’s Crest rims, which suited the cross-country intentions of this rubber perfectly. They’re definitely a ‘true’ 2.25″ tyre – compared to the generous dimensions we’re used to from the likes of Schwalbe and Bontrager, the Mitas treads are a bit narrower. The compound on the Textra treads is also quite firm. For now, Mitas only do Textra rubber in their CRX compound, which is really designed for durability and rolling speed. There are plans to introduce their dual compound Greyline rubber to the Textra range in the future, which we’d welcome for the increased side knob grip.

We’ve probably logged about 100km on these tyres to date (which is as far as many people on these tyres will ride in a single race) so we can’t claim to have ridden these tyres into the ground, but we’ve certainly got our head around how they perform. They’re a very fast set of treads, but with good bite in hardpack and sandy conditions too. If we were racing, we’d be very tempted to run the Scylla front and back, as it has sensational straight line speed, but with enough bite that you don’t approach every fast corner with your heart in your mouth. If conditions are looser, using the Kratos up front is a good option. Even though it has a chunkier tread pattern, it’s surprisingly fast too as the centre blocks are quite low profile. We were particularly impressed with its braking performance.

_LOW0042

If you’re looking for new rubber, that won’t leave you stranded in a pool of tubeless sealant as everyone else rides away, then give the Mitas Textra tyres a crack.

Both tyres have a really compliant ride quality too, conforming nicely to the terrain when we ran our pressures in the 25-27PSI range. Given these tyres don’t have a huge air volume, that suppleness is really important, helping keep a good footprint on the trail rather than skipping around.

If you’re a cross country or trail rider, then the 100-day sidewall guarantee alone makes these tyres a sound investment, especially if you’ve gone through the wallet emptying pain of binning near-new tyres in the past. These are great cross country treads, with performance characteristics that will be ideal for dusty, sandy Australian race tracks this summer. If you’re looking for new rubber, that will definitely go the distance and won’t leave you stranded in a pool of tubeless sealant as everyone else rides away, then give the Mitas Textra tyres a crack.

Fresh Product: Schwalbe Rock Razor

The fastest gravity tire. For the first time, we brought a “real” semi-slick to the Gravity and Enduro scenes. It’s a very interesting option especially on the rear wheel and for very fast, dry trails. These is no better tire for low rolling resistance than Rock Razor.

Technologies:

TRIPLE STAR COMPOUND MTB
Our best and most sophisticated compound. Triple compound. Perfectly adapted to the specific purpose.

PaceStar – Extremely fast XC compound

Easy rolling base layer (base)
Fast center (medium)
Grippy shoulders (medium soft)

TrailStar.
Enduro & Freeride Compound

Easy rolling base layer (base)
Grippy center (medium soft)
Extra-grippy shoulders (soft)

EVOLUTION LINE
The Evo tires offer the unique combination of low weight, excellent performance and optimum puncture protection. These are ensured by the high tech materials such as the Triple Star Compound, the HD Speed Guard against punctures, or the allround Double Defense protection with SnakeSkin side wall.

SUPER GRAVITY
Super Gravity has a new carcass construction at its core. The principle is a familiar one in motorbike tires. We have taken the best features and developed them further for the MTB. For SUPER GRAVITY the sidewalls are made up of four layers of carcass material, but there are only two layers underneath the cap*.

SNAKESKIN
One of our most effective inventions for Mountainbikes. SnakeSkin fabric adds only ca. 40-50 g per tire. This makes it the most practical protection against sharp rocks that can easily cut the side wall of light racing tires. SnakeSkin – in rocky terrain it is a great call!

TUBELESS READY
No tubes. Schwalbe Tubeless Ready tires make it possible. With three advantages – weight, puncture protection and low rolling resistance.

SUPER GRAVITY
Super Gravity has a new carcass construction at its core. The principle is a familiar one in motorbike tires. We have taken the best features and developed them further for the MTB. For SUPER GRAVITY the sidewalls are made up of four layers of carcass material, but there are only two layers underneath the cap*.

Fresh Product – Specialized Butcher DH tyres

Specialized Butcher DH tyres-1

The tread of choice for our World Cup DH Team. The Butcher tyres excel in even the gnarliest terrain with fast rolling, ramped centre knobs and perfectly sized shoulder knobs for bite in the corners.

  • Casing: 60 TPI, Dual Ply
  • Bead: wire
  • Compound: Base 70a / Top 42a
  • Pinch Protection: Butyl Inserts at bead
  • 26″ x 2.3; psi 25-50; approximate weight 1250g
  • 26″ x 2.5; psi 25-50; approximate weight 1290g

Flow’s First Bite: Specialized Ground Control and Purgatory Tyres

Specialized bikes are a little different in that they often come off the showroom floor with different tyres front and rear; a meaty tread up front with slightly faster-rolling rubber out back.

This mixing of tyres is seen more commonly on the bikes of  experienced riders who know exactly what they want out of their rubber, so it’s pretty cool to see Specialized offering this setup from stock. One of the common pairings on their trail bikes is a Purgatory up front and Ground Control out back, so we thought we’d give this selection a try too.

The Purgatory 29x2.3. Big, openly spaced tread blocks give the tyre the ability to bite into loose surfaces.
The Purgatory 29×2.3. Big, openly spaced tread blocks give the tyre the ability to bite into loose surfaces.

We’ve opted for the ‘Control’ version of both treads, rather than the lightweight S-Works version, as we’ve found the S-Works options a little fragile in the past. The Control versions are said to offer 15% more cut resistance, however the hell you measure this!

Both tyres are 2-Bliss Ready (butyl wrapped tyre bead) and sealed up tubeless very easily on SRAM Roam 50 rims. For a 2.3″ tread, the volume of both tyres seems smaller than we’d anticipated, but that’s probably because the Schwalbe rubber we’ve been using is notoriously oversized. Weights are 793g for the Purgatory in a 29×2.3 and 723g for the Ground Control in the same size.

Specialized Purgatory Ground Control-1

Both the Purgatory and Ground Control are 2-Bliss Ready.
Both the Purgatory and Ground Control are 2-Bliss Ready.

We’ve done around 15 hours on the treads to date and we’re completely sold on the Purgatory in particular thus far. We’ve been running pressures in the mid 20s (far lower than the stupidly high 35psi recommended on the sidewall) and while we’ve burped the front tyre once, the grip is excellent. Testing conditions so far have included lots of rock and sand, but also a smattering of dark root trails. The Purgatory has proved both supportive and tacky enough to hold an edge on the rocks, but also sensitive enough to find grip on the roots.

The Ground Control features lower-profile centre tread blocks and runs a faster-rolling and more durable 60a compound across the entire tyre.
The Ground Control features lower-profile centre tread blocks and runs a faster-rolling and more durable 60a compound across the entire tyre.

The Ground Control feels great too, rolling nice and fast with a 60a compound. We’ve pinged the rear rim a few times so far without any damage to the tyre, so that’s a good sign in terms of durability.

We’ll continue to run these treads for the next couple of months to get a better idea of their performance once some wear sets in.

While you’re here, check out some of the other tyres we’ve reviewed recently!

Bontrager XR4
Rubena Scylla
Maxxis Ardent
Bontrager XR2

Interview: Frank Stacy, Bontrager's Rubber Wizard

Frank Stacy’s life is an exercise in traction. A tyre engineer and designer, Frank has spent years defining that perfect balance we take for granted when we roll our treads out onto the dirt. During his recent visit to the Antipodes, Frank took some time out from field-testing to explain to us the challenges, processes and black arts of tyre design and construction. Here’s what he had to say.

 

The evolution of a tyre designer

I grew up in the motorcycle industry. My family owned a motorcycle dealership near Buffalo, New York and we all practised and raced together. Dad had an amazing work ethic and he was a top local racer. He taught me so much about the business, about motorcycle mechanics and how the smallest of changes to the bike, such as tyre pressure, tread pattern or suspension can add up to big gains on the race track. I’ve never forgotten this and I continue to emphasise this to the young riders I work with today: Pay attention to the little things. Small differences, they add up in the end.

Frank Stacy Bontrager Interview2
Frank Stacy and Emily Batty. Beauty and the Rubber Beast. No second guesses who’s who…

I raced motorcycles as a professional from age 18 to 28 when, in 1981, Dunlop Tire Corp hired me as their lead test rider. They sent me around the world to work with incredible groups of tyre engineers and test riders to learn the art of tread design, casing structure, rubber compounding, tyre manufacturing and tyre testing.

In early 1995 my wife Carol and I started our own company, Stacy Testing and Tire Specialist Inc. Later that year Specialized Bicycle Components approached me about designing and developing its complete tyre line for the US and the world. I worked with Specialized until June 2010 – after 15 years, I was eager to grow and focus on the latest technology and innovation in the bicycle tyre industry. I received a call from the tyre management team at Trek Bontrager. I met with them and after one meeting they had convinced me they were eager to improve, and that they would provide the backing needed to build the Bontrager tyre line to be a leading brand. So in July 2010 I signed on to be Bontrager’s director of Tire and Rubber Technology.

Frank Stacy Bontrager Interview3
Seeing Aaron Gwin on top of the downhill world riding Bontrager rubber must’ve been one hell of a feeling for Frank and Carol Stacy.

My hands-on experience in motorcycles has given me an advantage in what I bring to the bicycle tyre industry. I’ve always felt that off-road motorcycle tyres have a lot of cross-over to mountain bike tyres. For example, the tread pattern ‘land-to-sea’ ratio, the casing structure and the rubber compound are all key points. Where there is a big difference is weight and rolling resistance. These two areas are low priority on a motorcycle tyre because a motorbike has power to spare, but with bicycles it’s very different. Also, pinch flats on motorcycle tyres are almost non-existent, but they’re a huge factor for mountain bike tyres.

On working with Bontrager

Working with Bontrager now on its tyre program has been a very positive experience and I feel like we’ve made some great changes. The thing that surprised me the most when I came to Bontrager was that some of its factory mountain bike race teams were racing on other brands of tyres. This blew me away. First on my list was to prove to those teams that with their help and the right people behind the tyre program, we can make winning tyres. After one year of designing treads, casing structures and compounds, and tons of work, we now have all the factory mountain bike teams, and several support teams all using Bontrager tyres. We enjoyed huge success over the past two years in cross country, enduro and downhill. Seeing Aaron Gwin on the podium at the Downhill World Cups, arguably the best proving ground for mountain bike tyres, was definitely a good feeling.

Frank Stacy Bontrager Interview9

Proving the product at the highest levels is our top priority at Trek Bontrager. I’ve always been a believer in field-testing, and to me, results at the top tier of racing are a true indicator of tyre performance.

Having said that, there’s a huge development process that leads to a tyre being raced on that kind of stage, a mixture of both lab testing and rider feedback. I’ve always believed you have to understand the tyre’s intended application before you even begin. For example, for cross country, fast rolling and lightweight are a priority, traction a close second, with handling and wear in third. For downhill tyres, traction is way out front in priority, handling is second, weight is third and wear is a distant fourth. Once you have your priorities, you can begin to decide what the tread should look like and what materials are used for casing and compound spec.

Frank Stacy Bontrager Interview11

Designing rubber compounding is an art. There are four main properties in rubber compounds: polymer (rubber can be natural, synthetic or a mixture of both), carbon black (which affects the tyre’s durability, hardness and traction level, and makes the rubber black), oils (which alters traction and hardness) and fillers (basically to protect against cracking, ozone and those types of things). I’m not a chemist but I have many years of designing the basic formula for rubber compounds to learn which part of the formula affects what. I determine the basic formula by analysing competitors’ compounds through field-testing and laboratory research. Across the Bontrager tyre range we use around eight different compounds, some of which are proprietary to Trek Bontrager.

The best proving grounds

In terms of the actual testing, we focus on four main elements in the lab: rolling resistance, puncture and cut resistance, compound analysis and wet/dry traction. For some of our lab testing we engage a third party, based in Finland, too. The testing in the field is where my passion lies – I’m very hands-on with my testing programs. I monitor everything from the fitting of the tyres to tyre pressures, and I watch the tyres with my own eyes, on various areas of the course, and I collect data from the riders firsthand.

Frank Stacy Bontrager Interview15

The first thing I tell the test riders is, go out and learn your lines and set the bike up how you want it. Once you’ve done this, the only change we’ll make is to the tyres under you. Be consistent with each set of tyres: hit the same lines and do your best to carry the same amount of speed everywhere. If you mess up, throw that lap away and start over. I don’t need lap records, it’s most important to be consistent and pay attention to the small differences.

I’ve worked with several of the best riders in the world, motorcycle and bicycle. I’ve learned that just because someone can go fast doesn’t mean they will be a good test rider. It takes a certain feel to be a good test rider, and only a small percentage of racers have it. Over time it’s rewarding to see their education in tyre-testing develop and grow, and to ultimately choose the right tyre for the right conditions to race and win.

My wife Carol comes along to the tyre tests and takes photos. That gives us the ability to review the terrain and the surfaces after the test, and to compare with other tests we’ve completed. Additionally, Carol’s photos go with my test reports so the Trek staff can get a better visual of our test without being there.

Frank Stacy Bontrager Interview14

It’s undeniable that tyres have come a long way in the past 15 or so years. Just take a look at tubeless-ready technology for an example. Tubeless didn’t start out so good because too many companies rushed it to market before they understand the application. Now, however, even the weekend rider can set his or her tyres up tubeless and enjoy the benefits. Having said that, tubeless technology for downhill is one area where there’s room for considerable improvement. There are a few top brands testing downhill tubeless and this drives technology, but it’s not going to be nearly as easy as it was for cross country, trail or even road tubeless. Motocross tyres are still tube type – I worked on a motocross tubeless project for Dunlop Tires back in the mid 80s. Even though we won races with it, it had too many teething problems so it never went to production. But I’m pretty confident that, with Trek Bontrager design, technology and resources, we’re going to get it right, so stay tuned.

I’ve always said if you’re in it to be the best, you never down tools with design, development or testing – we’ve just scratched the surface of where tyres can go. I’m constantly searching for the next generation rubber compound, casing material and tread design… There’s always lots more to do!

 

Interview: Frank Stacy, Bontrager’s Rubber Wizard

Frank Stacy’s life is an exercise in traction. A tyre engineer and designer, Frank has spent years defining that perfect balance we take for granted when we roll our treads out onto the dirt. During his recent visit to the Antipodes, Frank took some time out from field-testing to explain to us the challenges, processes and black arts of tyre design and construction. Here’s what he had to say.

 

The evolution of a tyre designer

I grew up in the motorcycle industry. My family owned a motorcycle dealership near Buffalo, New York and we all practised and raced together. Dad had an amazing work ethic and he was a top local racer. He taught me so much about the business, about motorcycle mechanics and how the smallest of changes to the bike, such as tyre pressure, tread pattern or suspension can add up to big gains on the race track. I’ve never forgotten this and I continue to emphasise this to the young riders I work with today: Pay attention to the little things. Small differences, they add up in the end.

Frank Stacy Bontrager Interview2
Frank Stacy and Emily Batty. Beauty and the Rubber Beast. No second guesses who’s who…

I raced motorcycles as a professional from age 18 to 28 when, in 1981, Dunlop Tire Corp hired me as their lead test rider. They sent me around the world to work with incredible groups of tyre engineers and test riders to learn the art of tread design, casing structure, rubber compounding, tyre manufacturing and tyre testing.

In early 1995 my wife Carol and I started our own company, Stacy Testing and Tire Specialist Inc. Later that year Specialized Bicycle Components approached me about designing and developing its complete tyre line for the US and the world. I worked with Specialized until June 2010 – after 15 years, I was eager to grow and focus on the latest technology and innovation in the bicycle tyre industry. I received a call from the tyre management team at Trek Bontrager. I met with them and after one meeting they had convinced me they were eager to improve, and that they would provide the backing needed to build the Bontrager tyre line to be a leading brand. So in July 2010 I signed on to be Bontrager’s director of Tire and Rubber Technology.

Frank Stacy Bontrager Interview3
Seeing Aaron Gwin on top of the downhill world riding Bontrager rubber must’ve been one hell of a feeling for Frank and Carol Stacy.

My hands-on experience in motorcycles has given me an advantage in what I bring to the bicycle tyre industry. I’ve always felt that off-road motorcycle tyres have a lot of cross-over to mountain bike tyres. For example, the tread pattern ‘land-to-sea’ ratio, the casing structure and the rubber compound are all key points. Where there is a big difference is weight and rolling resistance. These two areas are low priority on a motorcycle tyre because a motorbike has power to spare, but with bicycles it’s very different. Also, pinch flats on motorcycle tyres are almost non-existent, but they’re a huge factor for mountain bike tyres.

On working with Bontrager

Working with Bontrager now on its tyre program has been a very positive experience and I feel like we’ve made some great changes. The thing that surprised me the most when I came to Bontrager was that some of its factory mountain bike race teams were racing on other brands of tyres. This blew me away. First on my list was to prove to those teams that with their help and the right people behind the tyre program, we can make winning tyres. After one year of designing treads, casing structures and compounds, and tons of work, we now have all the factory mountain bike teams, and several support teams all using Bontrager tyres. We enjoyed huge success over the past two years in cross country, enduro and downhill. Seeing Aaron Gwin on the podium at the Downhill World Cups, arguably the best proving ground for mountain bike tyres, was definitely a good feeling.

Frank Stacy Bontrager Interview9

Proving the product at the highest levels is our top priority at Trek Bontrager. I’ve always been a believer in field-testing, and to me, results at the top tier of racing are a true indicator of tyre performance.

Having said that, there’s a huge development process that leads to a tyre being raced on that kind of stage, a mixture of both lab testing and rider feedback. I’ve always believed you have to understand the tyre’s intended application before you even begin. For example, for cross country, fast rolling and lightweight are a priority, traction a close second, with handling and wear in third. For downhill tyres, traction is way out front in priority, handling is second, weight is third and wear is a distant fourth. Once you have your priorities, you can begin to decide what the tread should look like and what materials are used for casing and compound spec.

Frank Stacy Bontrager Interview11

Designing rubber compounding is an art. There are four main properties in rubber compounds: polymer (rubber can be natural, synthetic or a mixture of both), carbon black (which affects the tyre’s durability, hardness and traction level, and makes the rubber black), oils (which alters traction and hardness) and fillers (basically to protect against cracking, ozone and those types of things). I’m not a chemist but I have many years of designing the basic formula for rubber compounds to learn which part of the formula affects what. I determine the basic formula by analysing competitors’ compounds through field-testing and laboratory research. Across the Bontrager tyre range we use around eight different compounds, some of which are proprietary to Trek Bontrager.

The best proving grounds

In terms of the actual testing, we focus on four main elements in the lab: rolling resistance, puncture and cut resistance, compound analysis and wet/dry traction. For some of our lab testing we engage a third party, based in Finland, too. The testing in the field is where my passion lies – I’m very hands-on with my testing programs. I monitor everything from the fitting of the tyres to tyre pressures, and I watch the tyres with my own eyes, on various areas of the course, and I collect data from the riders firsthand.

Frank Stacy Bontrager Interview15

The first thing I tell the test riders is, go out and learn your lines and set the bike up how you want it. Once you’ve done this, the only change we’ll make is to the tyres under you. Be consistent with each set of tyres: hit the same lines and do your best to carry the same amount of speed everywhere. If you mess up, throw that lap away and start over. I don’t need lap records, it’s most important to be consistent and pay attention to the small differences.

I’ve worked with several of the best riders in the world, motorcycle and bicycle. I’ve learned that just because someone can go fast doesn’t mean they will be a good test rider. It takes a certain feel to be a good test rider, and only a small percentage of racers have it. Over time it’s rewarding to see their education in tyre-testing develop and grow, and to ultimately choose the right tyre for the right conditions to race and win.

My wife Carol comes along to the tyre tests and takes photos. That gives us the ability to review the terrain and the surfaces after the test, and to compare with other tests we’ve completed. Additionally, Carol’s photos go with my test reports so the Trek staff can get a better visual of our test without being there.

Frank Stacy Bontrager Interview14

It’s undeniable that tyres have come a long way in the past 15 or so years. Just take a look at tubeless-ready technology for an example. Tubeless didn’t start out so good because too many companies rushed it to market before they understand the application. Now, however, even the weekend rider can set his or her tyres up tubeless and enjoy the benefits. Having said that, tubeless technology for downhill is one area where there’s room for considerable improvement. There are a few top brands testing downhill tubeless and this drives technology, but it’s not going to be nearly as easy as it was for cross country, trail or even road tubeless. Motocross tyres are still tube type – I worked on a motocross tubeless project for Dunlop Tires back in the mid 80s. Even though we won races with it, it had too many teething problems so it never went to production. But I’m pretty confident that, with Trek Bontrager design, technology and resources, we’re going to get it right, so stay tuned.

I’ve always said if you’re in it to be the best, you never down tools with design, development or testing – we’ve just scratched the surface of where tyres can go. I’m constantly searching for the next generation rubber compound, casing material and tread design… There’s always lots more to do!

 

Tested: Rubena Scylla Tubeless Supra 29” Tyres

Rubena is a Czech based tyre company that has been making a big impact on the local Australian cross country scene in recent times. Ben Henderson is behind the distribution and as a highly accredited racer, we weren’t surprised to see these aimed squarely at the XC rider and racer where speed, grip and low weight are most sought after tyre attributes. Received for testing was the Scylla Tubeless Supra’s with a dual-compound Scylla GreyLine version as a front tyre and the more durable single compound Black version as a rear. The Scylla is available in a variety of different compounds, construction and diameters, however we tested the 29 x 2.25” size.

Web_Test_Rubena_tyres-4
Rubena Scylla Tubeless Supre 29″.

Using a floor pump, we experienced no issues seating and sealing these tyres tubeless onto Stan’s rims; not always the case with superlight tubeless ready tyres. Once inflated, at just .6mm shy of our often go to benchmark; the Schwalbe Racing Ralph 2.25”, the Scylla offers a decent bag size but just shy of being an actual 2.25”.

Web_Test_Rubena_tyres-2
Greyline – with it’s softer compound is a great front tyre.

With a combination of the softer compound grey version on the front and the longer wearing black version at the rear, we experienced a superb combination of confident traction and speed with excellent durability. The tightly spaced knob pattern didn’t suit the rockiest or loosest of terrain, however for hardpack to intermediate conditions we were confident in the available traction when pushed hard.

Fast rolling with confident traction in a durable yet lightweight construction, it’s no wonder the Rubena Scylla’s have such an impressive list of race wins.

Web_Test_Rubena_tyres-3
Small directional knobs help the Scylla roll faster.

 

Fresh Product: Maxxis Minion DHR II Tubeless Ready tyres

Finally, Maxxis have released a mid-weight tubeless-ready version of their most popular tyres! If you wanted to go tubeless with Maxxis previously you’ve had to choose between either a heavier LUST tyre or risk running a non-tubeless tyre (which tended not to seal up as well).

The trail version of the Maxxis Minion DHR II features the same tread pattern as its downhill counterpart, but uses a single-ply casing to reduce weight. With side knobs borrowed from the legendary Minion DHF, but widened to provide more support, the DHR II corners like no other. The center tread features ramped knobs to improve acceleration and sipes to create a smooth transition when leaning the bike. Paddle-like knobs on the center tread dig in under hard braking and help keep the bike under control. Pair it with a Minion DHF up front for the ultimate aggressive trail riding tire combo!

Schwalbe Racing Ralph Evolution Series

The Racing Ralph, from Schwalbe, is a designed for speed, and the tubeless ready Evolution model with ‘Double Defense’ technology adds that extra bit of durability to the sidewalls for those who need it.

We got to test these at our local trails in Sydney and found them fantastic – albeit they wear a little quickly. [private]

Set-up was easy and we got these to seal (tubeless) with relatively little effort.  Also, the tyres kept their seal and remained flat free for a solid 300km of delicious trail riding.

The tyre rolls fantastically fast, and while there is not a huge amount of depth to the tread, traction was decent in all but the loosest trail surfaces.

Cornering was also very predictable thanks to the soft compound tread and the round profile of the tyre.  We did however find that we lost confidence once the tread started to wear as the knobs would flex significantly.  This was more evident on rock surfaces -which led to a few hairy moments.

The durability and relatively quick wear was our only beef. As with most performance tyres, it’s a trade-off between performance and durability and for those not willing to make the trade-off for performance, maybe a longer wearing tyre would suit.

An excellent tyre that performs extremely well. The only draw back is the wear, but that’s the sacrifice you make for the good performance.

 

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ERW – Airless Bicycle Tyres

Welcome to the future of bicycle technology. ERW©

The benefits of removing the air from tires completely has been known since the beginning. ERW© Patented Airless Design make bicycling safer and more efficient. Obstacles slide under the ERW© wheels with precision and ideal comfort, and keeping the tread on the tire. Our design can be created to have fully adjustable tread ride comfort, road or trail conditions.

The future is rolling forward, hitch a ride.

 

Kenda Small Block 8

The Kenda Small Block Eight is a great hardpack cross-country race tyre. But the Small Block Eight is not limited to hardpack – it’s more than capable of tagging along on any adventure you choose. Just make sure you’re ready for the ride.

The tread uses Kenda’s Dual Tread Compound, and has a hard compound in the centre and Sticky-E on the side. The tyre’s low-profile tread has a subtle ramp to the centre knobs, giving the tyre a low rolling-resistance, which is so important in a race tread.

The side-blocks are situated close to the centre of the tread. This gives the Small Block Eight a small footprint and makes it a fast-roller. It also means traction is reduced and it takes longer for the tread to bite in when the bike is leant over heavily through corners. To be fair, though, few cross country racers on 29ers are looking to lay their bikes over on a regular basis, so the low rolling-resistance of the Small Block Eight definitely outweighs that negative.

The casing on the Small Block Eight is made of Kevlar, which adds a little weight but provides that extra strength for a tubeless-specific tyre.

But be careful when setting the Small Block Eight up tubeless. This tyre seals much better on a tubeless-specific wheel than on a simpler, converted type. We had the Small Block Eight blow off a DT Swiss wheel we’d converted to tubeless with Stan’s – twice. (The second time, it was at 40psi!)

So if you haven’t run tubeless on your rims before, or you know they are on the narrow side, there is the risk that you’ll end up having to run these thoroughbred racers with tubes.

The DT Swiss wheel does have a narrower rim – once we matched the Small Block Eights with a wider, tubeless-specific rim, the tyres sealed up just fine with a track pump. We didn’t even need sealant to initially bead the tyre. Though the Small Block Eight is not a true UST tyre, Kenda markets it with Sealant Compatible Tyre (SCT) technology, and it is designed to be run with tubeless systems.

The Kenda Small Block Eight definitely meets the brief of a 29″ cross-country tyre – it’s a fast-rolling tyre offering confident central-tread traction, making it perfect for hardpack. The Small Block Eight won’t tick all the boxes for everyone, however. But then, it is a purpose-specific tyre. It’s not supposed to.

Kenda Small Block Eight – a fast-rollng confident tyre.

 

Continental X-King 2.2 ProTection tyres

Continental tyres are simply massive in Europe. Along with Schwalbe, they dominate the spec of most Euro bike brands. But they’ve been pretty quiet in Australia/NZ of late so we weren’t sure what to expect when a box with the distinctive yellow and back Conti branding landed at Flow HQ.

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The X-Kings are billed as a bit of an all-rounder, a claim that can sometimes mean mediocrity on all fronts. We’re very pleased to announce that isn’t the case here and the X-Kings have proved to be a great set of treads for general cross country and trail use.

These particular tyres feature Conti’s ProTection casing and Black Chili compound technology and they’re made in Germany, mein freund.

Out of the box and straight onto the scales they went, with a pleasing reading of just 588g blinking back at us. For a 2.2″ tyre, especially one with a reinforced sidewall, that’s an impressive figure.

While these aren’t a UST tyre (Conti actually do have proper UST version) we decided to seal them up tubeless on a some Shimano wheels. The stiff sidewall of the ProTection casing made them a little tricky to bead, but once they snapped into place the seal was tight and we experienced very minimal air loss.

Profile wise, they’re quite a tall tyre, which encouraged us to drop the pressures a little lower than normal without too much fear of denting the rims.

The tread pattern looks bitey, and it is, finding good traction in both hardpack and looser, sandy soils. We’ve been spending a lot of time on some of the gummy offerings from Maxxis, Kenda and Schwalbe lately, so it was a pleasant surprise to find that even though the Contis don’t feel as sticky, they actually delivered plenty of cornering bite on the trail.

But because the tread blocks are quite closely spaced, particularly through the centre, it’s still a very fast rolling tyre too. Straight line braking in loose conditions was a the only chink in this tyre’s armour. The tight tread pattern across the tyres centre battled to dig in sometimes, though perhaps the 2.4″ version with a bigger contact patch would do better up front for hard riding.

After a few weeks of use, there is some wear becoming apparent, but not what we’d term excessive. We’ll bring you a long term update down the track.

Conti claims that their Black Chili compound strikes the perfect grip/speed/durability balance, and we think it’s pretty optimum. After a couple of week’s solid use, the rear tyre had begun to show some wear with slight tearing on some knobs, but we certainly wouldn’t call it excessive. The sidewalls continue to live up to their name, and are in great condition too.

All up, we’d be happy to run these tyres as our day-to-day treads, from trail riding to marathon races. They’re a top all-rounder, just like it says on the box. Sehr gut! [/private]