We knew wide rims were going to catch on, since we reviewed these wheels almost 12 months ago the mountain biking fraternity has seen the rise and reality of more than just wide rims, we now have 27.5+ bikes. All this time we’ve been rolling around on what was pretty much a plus bike, it just wasn’t called one as such.
The 27.5″ Ibis 741 wheels are 35mm wide (internal width), we fitted them to our Trek Fuel EX with 2.4″ Bontrager XR4 tyres. These are not ‘plus’ size wheels, they use standard width hubs, on 27.5″ diameter rims. So if you’re interested in the benefits that a plus bike has, but already have a nice bike a set of these wheels would bring it pretty close in performance to the new breed of ‘semi fat’ plus bikes.
It was riding these wheels which has started our affinity for bigger bagged rubber on trail bikes, the way they transformed our bike into a traction machine was unmistakable. But as you would read in the review below, the set of wheels we were using developed cracks around a few of the spoke nipple holes. The wheels were swiftly replaced, and we sent them back to Ibis HQ in Santa Cruz, CA for inspection. Here was the official word from Ibis:
Regarding the spoke hole problem, that’s unusual (1 time) and would have been covered under our warranty.
The carbon is reinforced at each spoke hole so that the rim pull through strength is more than 2x the strength of the spoke. So the spoke will normally break long before the rim will crack. It looks like the spoke hole reinforcement material was not lined up with the spoke hole drilling, or did not mould correctly. Currently there are specific places for the reinforcements in the tooling to keep everything lined up, so this should not be a reoccurring problem.
So that was that, the replacement set of wheels are still fitted to the Trek Fuel to this day, and we still love them to bits.
The Ibis wheels took a break from the Fuel EX, and came over to Queenstown, NZ with us fitted to a Trek Remedy for some big mountain shredding. And we mean SHREDDING! There has been not one sign of any repeat issue in the carbon.
Going forward, they will now come with a DT 350 rear hub.
Read below for our initial review on the wheels.
Wider rims on bikes are inevitable, there is no doubt it’s going to be the next big thing. We’re so confident that the trend of wide rims will spread into all genres of mountain bikes, that we’ve been wondering why it’s taken so long?
Ibis are best known for making curvy and fluid carbon bikes like the Mojo or Tranny, but a few sets of wide rimmed wheel sets have appeared in their catalogue recently. These new Ibis 741 wheels are carbon, subtle in appearance and have an internal width of 35mm, now that is really bloody wide. Using pretty standard looking hubs with Enduro sealed bearings (new wheels will now ship with a DT Swiss 350 rear hub) these wheels don’t cry out ‘look at me!’ like many carbon hoops around, they almost make it look like you’re riding a fat bike, but what they do to your ability on the trails is astounding.
Many of you may remember riding rims with such width in the early days of mountain biking, most likely steel or heavy aluminium. Now it appears history is repeating itself now that carbon technology has advanced so far. These wheels are available in a 650B/27.5″ size, and the Ibis 941 set for 29ers.
It’s all about traction, and it’s that connection with the dirt that us mountain bikers seek. When there is no traction we hit the deck and that hurts, so imagine if you could add traction to your bike without adding weight to a place on your bike like your wheels? Well, you can.
Wider rim gives your existing tyre a greater contact surface with the ground. Taking the exact same tyre and fitting it to a wheel with a wider rim clearly shows the tyre looking visibly bigger and having more volume. The tyre also has a stronger stance, and withstands rolling around on the rim. With a 35mm internal width, these are a whole lot wider than your average mountain bike rim. Most traditional all-mountain rims are around 21-23mm, but we’ve seen brands like Specialized and ENVE pushing for a wider width. Specialized’s Roval Traverse SL Fattie wheels are also a beefy 30mm wide.
It took us about three minutes on the trail to make up our minds, and another three to completely confirm that wide rims are the way forward. You know that feeling when you get a flat tyre, but before it loses all the air you have that fleeting moment of magic traction? Well imagine that all the time, but without the tyre squirming, or dragging along or stopping to fix it.
We used the Ibis 741 wheels on two bikes, a Giant Trance Advanced SX and a Trek Fuel EX 9.8. Switching between the standard wheels and the Ibis felt like you suddenly had the bike handling skills of Sam Hill. We were literally throwing our bikes into the turns, harder than usual, and with new-found confidence. Rolling resistance on the trail is reduced too, with lower tyre pressures, the bike rumbles over the rougher surface with less resistance, and without pinging back off rocks or roots.
We didn’t drop the pressures enough on the first ride, and we kept going lower and lower until our tyres were running less that 20 psi. Dropping the pressures down unlocked the full potential of the wide rims, aiding the traction in corners, climbs and slippery roots like mad. With such low pressure, we never rolled a tyre off the rim or burped air from the tubeless system.
The Ibis wheels made our 120mm travel Trek Fuel feel like it had 130mm, that may sound silly, but that is exactly how it felt. Rocky terrain seemed less intimidating, and climbing up the steepest single tracks all of a sudden became a reality. We walked less climbs, hit corners harder and rode our bikes looser and more relaxed than before. Terrain was opened up to us, we felt like cheats. The trade off is increased drag on the ground, you can hear and feel your tyre’s knobs rumbling over the trail surface. But we were so happy with these wheels where it mattered the most, that we found the trade off to be perfectly acceptable.
They are really going to suit the trail bike rider with an all mountain attitude, they are light enough to drop weight out of stock bikes, and stiff enough to not feel like you’re riding a traditional lightweight set of wheels.
After a few good months of testing, the wheels stayed true and the hubs spinning fast and smooth, but we did notice a slight amount of carbon cracking around one of the nipples on the rear wheel, and two more showing a signs of stress. We immediately let the Ibis folks in Australia know, and their response was – “We haven’t seen or heard of this happening since the release of the wheels, and are confident that it was an anomaly. Ibis will be giving comment upon inspection of the fault by their engineers at Ibis HQ”. Ibis are going to take a look at our set of wheels, and also send out another set for a longer term test, so stay tuned.
In the end, we’re happy to be continuing a test on the 741s. They allow you to ride harder and in more control as if you are magically riding on ‘hero dirt’ all the time, and that is a very good thing.
So, this set is going back to Ibis, and we’ll keep on flogging the replacement set all summer long.