Dan reviews the Polygon Siskiu TE
The Polygon Siskiu TE is a brand new e-MTB for 2023. Joining the existing Collosus NE (formerly known as the Mt Bromo), the Siskiu TE utilises a simpler suspension design and features a little less travel. Along with the new Shimano EP801 motor and a value-oriented component package, the Polygon Siskiu T7E looks to be a rather appealing package for the price. So, does it deliver on the trail?
Watch our Polygon Siskiu TE video review here:
It’s a lot of bike for the money, as you’d be paying thousands more to get an equivalent Specialized Levo or Trek Rail.
An overview of the Polygon Siskiu TE
The Polygon Siskiu TE is designed to be a versatile all-round trail bike. It’s built around a hydroformed alloy frame and is equipped with a 150mm travel fork and 140mm of rear travel. It rolls on 29in wheels, though a flip chip in the lower shock mount means it can also accommodate a 27.5in rear wheel for those wishing to try the mullet thing.
Just like the non-motorised Siskiu T, the Siskiu TE gets a single pivot suspension platform. The seatstays drive the shock directly, with a compact rocker link helping to control the leverage rate. The shock layout gives just enough room underneath for an itty-bitty bottle and cage.
Powering the entry-level Siskiu TE is a Shimano EP6 motor and 504Wh battery, while the higher-spec’d model gets an EP801 motor and 630Wh battery. Whatever the size, the battery can be easily removed from the downtube with a 4mm hex key for charging separately.
Polygon Siskiu TE geometry & sizing
There are four frame sizes to choose from in the Polygon Siskiu TE range, and overall geometry isn’t too far different to the slightly longer travel Collosus NE;
- Head angle – 65°
- Seat angle – 77°
- Reach – 445mm (S), 465mm (M), 485mm (L), 505mm (XL)
- Stack – 618mm (S-M), 627mm (L), 641mm (XL)
- Rear Centre – 445mm
- BB Drop – 39mm
In addition to being able to fit a 27.5in rear wheel thanks to the flip chip in the lower shock mount, the Siskiu TE is rated for use with up to a 160mm travel fork. This would slacken out the geometry a touch and lift the BB.
2023 Polygon Siskiu TE price & specs
There are just two models in the Polygon Siskiu TE lineup for 2023, and both are priced very well compared to the competition.
Prices start at $5,499 AUD for the Siskiu T6E, which comes with a Shimano EP6 motor, a 504Wh battery, a Deore 1×10 drivetrain and a cheaper Suntour fork and shock.
The model we’ve been testing is the Polygon Siskiu T7E, which has a current retail price of $6,599 AUD. This gets you an upgrade to the Shimano EP801 motor, Suntour Aion 35 fork, a piggyback shock and a SLX 1×12 drivetrain. It’s a lot of bike for the money, as you’d be paying thousands more to get an equivalent Specialized Levo or Trek Rail.
Part of the reason for the impressive pricing is because in Australia, Polygon bikes are shipped directly to your door through the local distributor BikesOnline. You will have to add a relatively small amount for shipping, and there’s some minor assembly required to get the bike rideable out of the box.
Polygon Siskiu T7E
- Frame | ALX Alloy, Single-Pivot Suspension Design, 150mm Travel
- Fork | SR Suntour Aion 35, RC-PCS Damper, 51mm Offset, 160mm Travel
- Shock | SR Suntour TriAir2 3CR, 210×55mm
- Drive Unit | Shimano EP801, 85Nm
- Battery | Shimano BT-EN806, 630Wh
- Wheels | Shimano MT400 Hubs & Entity XL3 Alloy Rims, 35mm Inner Width
- Tyres | Schwalbe Hans Dampf 2.6in Front & Rear, Super Trail Casing & ADDIX SpeedGrip Compound
- Drivetrain | Shimano SLX 1×12 w/34T Alloy Crankset & 10-51T Deore Cassette
- Brakes | SRAM Code R 4-Piston w/203mm Rotors
- Bar | Entity Expert Alloy, 25mm Rise, 780mm Width
- Stem | Entity Expert, 35mm Length
- Seatpost | TranzX Dropper, 30.9mm Diameter, Travel: 150mm (S-M), 170mm (L-XL)
- Saddle | Entity Xtend
- RRP | $6,599 AUD (plus shipping)
I was pleasantly surprised at its confident handling and the ability to charge pretty hard on some steep and rough trails, especially with ‘only’ 140mm of rear travel.
Polygon Siskiu TE weight
Confirmed weight on our Polygon Siskiu T7E test bike is 24.66kg. That’s not a bad weight for an alloy e-MTB with a full-size motor and battery, and especially one at this price point.
We’ll point out that while we did weigh our test bike without pedals, that figure does include inner tubes as that’s how the bike comes out of the box. Thankfully the rims are taped from the factory, though you will need to purchase valves and sealant separately in order to set up the wheels tubeless.
Testing the Polygon Siskiu TE
We put the Polygon Siskiu T7E into the hands of our rowdy enduro test rider, Dan MacMunn. Dan has previously tested the Norco Sight VLT and Trek Rail, giving him a good basis for comparison. Mind you, both of those bikes cost many thousands of dollars more than the Siskiu TE, so we were all very curious as to how the Polygon would compare on the trail.
Here we chat with Dan about his experience of testing the Siskiu TE over the past few weeks.
How have you found the overall fit and sizing?
I’m 183cm tall and the Large feels spot-on. The seated climbing position is comfortable and the top tube doesn’t feel overly long.
The Entity-branded grips are good and the bars feel neutral with a nice sweep profile. I’ve gotten along well with the saddle, which has a textured patterning on the top that helps to keep you from sliding backwards on steep climbing sections.
Tell us a bit about your suspension setup
For my riding weight of 82kg, I put 75psi in the fork and 175psi in the shock, which translated to 20% sag on the front and 30% sag at the rear.
I did find the adjustment range lacking on the damping, especially for the Suntour Aion fork. Even with the rebound dial set all the way fast, the fork’s rebound speed was too slow. To a point this is personal preference, but given how comically slow the rebound damping is at the other end of the spectrum, I think the tuning range could do with some improvement.
It was a similar story in the rear, where I only used two clicks of rebound damping off the fastest setting. The shock also has a 3-position compression adjuster that gives you Open/Medium/Firm settings. I found these to be useful, especially when seated climbing on smooth fireroads as the suspension is pretty active under pedalling. Climbing traction is excellent, and the back end delivers a pretty neutral feel across braking bumps on the descents.
What do you dig about the Polygon Siskiu TE?
For value for money the Polygon Siskiu TE is a pretty solid overall package. It rides really well, especially on the descents. I was pleasantly surprised at its confident handling and the ability to charge pretty hard on some steep and rough trails, especially with ‘only’ 140mm of rear travel.
If you’re exclusively shuttling on mega steep terrain and hitting double black diamond trails, sure, you’d want a bit more travel and a slacker head angle. But for most of the popular riding spots in Australia, the Siskiu TE feels like it has enough travel.
The geometry is spot-on and I felt comfortable on the bike pretty quickly. It’s particularly adept on fast descending trails with plenty of turns, as it’s great fun tipping in and railing through berms and ruts.
How have you found the new Shimano EP801 motor?
Firstly the positives. The Shimano EP801 is a great motor, being impressively responsive and quiet in its power delivery. The freewheel mechanism still makes noise on the descents, but it is quieter than the previous EP8 motor. The rattle is quite a dull sound, making it less noticeable compared to an equivalent Bosch drive unit.
Top-end power has improved slightly with the EP801 motor, but it’s still not as punchy as a Bosch, which is noticeable on steep pinches. I also found the stock Trail mode to be a bit lacking. It takes quite an effort to get on top of the motor and draw the maximum assistance out of it, and it feels like that support drops off easily if you lag slightly.
You can tune the motor’s settings using Shimano’s E-Tube app, which allows you to adjust the Assist Character, Max Torque and Assistance Start of each of the three modes. Furthermore you can switch over to the ‘Fine Tune’ mode that provides five different Trail settings in between Eco and Boost, giving you a fair bit of control over the motor’s output.
That said, the app isn’t the most refined user experience, and once I synced the bike couldn’t actually update the adjusted figures to the bike. I’m personally not one to muck around with that sort of tech, and would rather have the bike felt right from the box. As such I rode almost exclusively in Boost mode, which as mentioned still lacks some grunt, especially when the trail steepens.
What has the bike struggled with?
The suspension is the biggest thing holding the Polygon Siskiu TE back. The geometry means it still descends really well, but the fork and shock lack sensitivity, and that means overall grip, comfort and stability suffers as a result.
There is considerably less small bump compliance compared to more established offerings from the likes of Fox and RockShox. This is especially the case with the Aion 35 fork. I’d say the slow rebound damping has a lot to do with this, as the fork doesn’t seem able to recover fast enough to keep it in the sweet spot at the top of the travel.
It’s not such a big deal on smoother and flowier trails, but it is a problem on rough and high-speed sections of trail where the tyres struggle to maintain consistent contact with the ground. More feedback is transmitted up from the front wheel and into your arms, resulting in notable fatigue on longer rides.
Component Highs & Lows
Most of the components on the Polygon Siskiu T7E have been solid throughout testing. Throw in the fact that you’re getting a great motor and a good sized battery, and it represents decent value for money.
The wheels and tyres have been great, and I was surprised that the Schwalbe Hans Dampfs managed to hold their own during some very slippery and wet winter conditions of late. The Super Trail casings are very supportive, and along with the big 2.6in width you can run quite low pressures to help eke out more grip. There were no flats or rim damage inflicted throughout testing, despite not running inserts.
All the contact points look good and perform really well, and the Shimano SLX drivetrain is solid. The TransX dropper is nice and long and performed without issue.
Are there any components that are holding it back?
Mainly the fork and shock. As mentioned above they’re both lacking a bit of responsiveness, especially over smaller bumps. The fork also suffered from some pretty serious bushing knock, which was apparent and annoying while riding. I do love the integrated mudguard though, which is a nice touch.
The SRAM Code R brakes are plenty powerful, but I find they’re sensitive to pad wear and require regular bleeding to ensure they feel solid at the lever.
It’s worth mentioning that the Siskiu T7E comes suppled with a side-entry bottle cage and a very small 425ml bottle. It’s only a couple of sips worth, so you would have to consider alternative ways of carrying water on any longer rides.
Have you had any issues with any of the parts or the frame itself?
I did have an annoying issue with the headset. This features a pretty flimsy steering limiter that sees the crown race locking into the back of the fork crown with a grub screw. The crown race then has a notch on the front of it that sits in a corresponding groove in the lower headset cup.
During a fairly innocuous crash that saw the bars twisted around, the steering limiter locked hard enough that the grub screw was actually forced out of its little pocket on the crown. This bent the crown race out of place and caused the headset bearing to bind up badly. It was a bit of a mission to solve and required some filing of the crown race to get it somewhat back in to place.
BikesOnline ended up sending us out a replacement lower headset and a standard crown race, which sorted everything out. We think Polygon needs to go back to the drawing board with the headset design or get rid of the steering limiter altogether as it’s potentially going to cause issues for Siskiu TE owners.
How did the Polygon Siskiu TE compare to the Trek Rail you tested?
Overall the Trek Rail is a much more refined package than the Polygon Siskiu TE, as you would expect given the price difference. The Rail 9.8 XT I tested costs almost twice as much as the Siskiu T7E, which puts things in perspective. Trek does offer cheaper models, but you’re still looking at $7,499 AUD for the base-level Rail 5.
I prefer the power and responsiveness of the Bosch motor on the Rail, but it’s really the quality of the suspension that sets it apart from the Siskiu TE. The suspension on the Rail is amazingly supple, and it provides a load of grip and comfort on a wide variety of terrain. Otherwise the geometry and handling aren’t too far different.
It’d be interesting to try out the Siskiu TE with a higher quality fork and shock, as I think the performance gap between these two e-MTBs would narrow significantly. Perhaps that opens the door for Polygon to introduce a Siskiu T8E?
Polygon Siskiu T7E vs Collosus N8E
With the recent introduction of the Siskiu TE, some riders might be wondering how it compares to Polygon’s existing e-MTB; the Collosus N8E (formerly known as the Mt Bromo). This is an interesting question because while the two bikes share many similarities, there are also some considerable differences.
For a start the Collosus N8E features more travel with 160mm front and rear. It utilises the 6-bar IFS linkage that does a great job of isolating the rear suspension from pedalling and braking inputs. There are a lot more pivots and bearings to worry about though. Personally, we prefer the simpler single pivot layout of the Siskiu T7E.
Geometry is close between the two bikes with the Collosus N8E having a marginally slacker 64.5° head angle. The rear centre length is insanely short at 435mm thanks to the elevated chainstays, but otherwise the overall proportions are much the same.
As for price, the Collosus N8E retails for $7,999 AUD. That’s quite a bit more than the Siskiu T7E, though you do get a lot of upgrades for $1,400 including a Fox 38 fork, a Float X2 shock, Shimano XT brakes and Schwalbe Magic Mary tyres. The rest of the component list is pretty similar and both bikes feature an alloy frame and a 630Wh battery. The Collosus N8E does come with the slightly older Shimano EP8 motor though.
So which one should you pick? If you’re on a tight budget and are typically riding smoother and flowier singletrack, the cheaper Siskiu T7E will no doubt be up to the task. If you’re frequenting enduro-type trails on steeper and more technical terrain, and you can afford the premium, the Collosus N8E is potentially the better choice. The higher spec suspension will offer a smoother ride with more grip and greater adjustability.
Our experience with the Polygon Siskiu TE has proven to be something of a mixed bag.
It’s certainly an appealing bike for the money thanks to its sturdy alloy frame, straightforward suspension design and Shimano motor and battery. Most of the spec is solid and has stood up well to being ridden along some pretty rowdy and technical trails.
We were less impressed by the suspension however, as it lacks sensitivity. The bushing knock in the fork was annoying, and the rebound damping is far too slow.
It’s a shame because the geometry and handling on the Siskiu TE are fantastic. For that reason we’d love to see Polygon offering a higher-spec model with RockShox or Fox suspension to take the performance to the next level.
Of course the low price of the Siskiu T7E relative to its big-name competitors means you could pocket the savings to invest in future upgrades as your riding and skills progress over time. That makes it a good option for a budget-conscious rider who’s looking to make their first foray into the world of e-MTB.