Polygon's Siskiu models sometimes fall into a forgotten area of mountain bikes. With 120mm or 140mm of travel, mid-range geometry numbers and relatively attainable pricing, these trail bikes don't tick off any buzzwords, but should offer real-world performance.
Polygon offers two wheel sizes, with the Small and Medium rolling 27.5-inch wheels, and another Medium, Large and X-Large wearing 29-inch rubber. The XL Siskiu T8 I have in for testing has the larger hoops.
Polygon Siskiu T8 specs
- ALX aluminum frame
- Faux bar rear suspension, 140mm travel
- 140mm RockShox Revelation fork, Deluxe rear shock
- Shimano XT/SLX groupset, 1x11-speed
- Entity XL2 wheels with Schwalbe Nobby Nic tyres with Addix Speedgrip compound
The lowdown on the frame
The all-aluminum Siskiu T8 is like a friendly reminder of bikes from the turn of the century. Back then, carbon on bikes hadn't come of age, so mountain bikes were made of metal.
Also going back to those days is the Siskiu T8's silhouette and rear suspension design. For years, Specialized held the patent on the Horst link, which forced nearly every manufacturer to place the rearmost pivot on the seatstays, rather than the chainstays. I like that Polygon makes no qualms about it, calling its rear end 'Faux bar'.
The geometry is a mix of old and new school. The head angle is a relaxed 66.5 degrees and the seat angle is a rarely seen, super-relaxed 68.5 degrees. The bottom bracket is low at 337mm, while the stack and reach line up with modern numbers of 627.6mm and 475mm respectively.
Parts-wise the Siskiu T8 comes fairly well equipped. RockShox handles the hits with a Revelation RC Solo Air fork and a Deluxe RT3 Debonair shock that's claimed to have a special tune.
Drivetrain duties are clicked off by a Shimano SLX shifter moving an XT rear derailleur over 11 speeds, while non-series Shimano discs reel in the go.
The wheels are Polygon's house brand Entity, and are Boost spaced. Tires are Schwalbe's Nobby Nic with Addix Speedgrip compound, which is likely a concession to getting the price-picked wheels moving a bit quicker.
Polygon Siskiu T8 ride impression
On the uphills the ride felt really stiff but not in a fast, efficient way. Even at 25 percent sag on the shock the rear tire seemed to be deflecting off rocks and trail debris rather than maintaining traction. The lever was in Open mode, but the shock felt like it was half stuck in Locked mode.
I found the same sensation on the front. The Revelation fork looks the business being all blacked out, but its up-and-down action didn't match its appearance. It's a price-conscious spec for certain, but even with that in mind the compression feels as though it was stuck on Firm mode even though I had the low-speed compression all the way open.
I decreased the air pressure well below the recommended range for my weight, and while it did make a difference, it still felt harsh off the top and I still couldn't get full travel.
On the downs, things were better. The Shimano MT500 discs clearly didn't have loads of power, but the admirable modulation seemed to make up for it.
The wheels felt heavy when getting on the gas but I appreciated the nearly silent rear hub.
Unfortunately the Schwalbe Nobby Nic tires were pretty horrendous. They have the Speedgrip compound, which felt plastic-like. On my well-ridden test loop, they actually tossed me on the ground after sliding sideways off a root.
That's a lot of negatives, but the ride was actually a lot of fun. The short stem made it super playful and it was easy to loft the front wheel for manuals or jumping.
The modern long and low geometry provided a very carve-happy sensation, especially when driving my weight through the bottom bracket. And the frame and wheels felt decently stiff when landing jumps like a goon.
Polygon Siskiu T8 early verdict
In my full review I'm likely going to repeat "For a $2,500 bike..." a lot, because everything this bike does and doesn't do needs to be qualified with this. As for the early verdict, I was very surprised by the ride of the Siskiu T8.
It felt balanced and was extremely easy to ride. I was shocked at how well it liked being on its back wheel and how well it went around corners despite the hard compound tires.
There are a few components that I might switch up and I'm really hoping the suspension gets better with more hours of ride time. If not, I'll likely open it up and make sure things are as they're supposed to be.
Polygon's Siskiu T8 comes in at a refreshingly attainable price of £2,500 / $2,500. The lower end Siskiu T7 retails for £2,000 / $1,899. Polygon sells its bikes online and through select bike shops.