Polygon’s new Siskiu could be a budget trail shredder

We last reviewed the Siskiu D7 back in 2017 and found that despite the bike having a great overall feel, it did suffer from some slightly questionable forks that flexed at the first opportunity and tyres that struggled to grip when it got wet and sloppy.

It looks like Polygon went back to the drawing board, building on their capable chassis with a host of new and better-performing parts. The new Siskiu D7 could be contending for your cash, riding hot on the heels of Marin’s highly-acclaimed Rift Zone 1.

Polygon Siskiu D7 frame details

With 120mm of travel, the Siskiu uses a four-bar style rear suspension system where the rear wheel is bolted to the chainstay rather than the seat stay. The bike has internally-routed cables and while it doesn’t feature a dropper post, it’s dropper-ready.

The bike uses size-specific wheels: the smaller 15.5” frame has 650b hoops while the 17inch frame can be used with either 650b or 29inch wheels. The larger bikes — 19inch and 20.5inch frames — get 29-inch wheels and all frame sizes have a tapered head tube.

Polygon Siskiu D7 geometry

The Siskiu has promising geometry for a budget 120mm travel trail bike. The 19inch, 29er size large bike has a 76-degree effective seat tube angle, a 67.5-degree head angle, 465mm of reach and a 1189mm wheelbase with a 436mm chainstay length.

The 650b bikes get 432mm chainstays, a 70-degree seat tube angle and a 67-degree head angle.

Polygon Siskiu D7 spec
Despite sponsoring plenty of top-level riders, Polygon’s name is still relatively unknown in the West.  Alex Evans

This is where the Siskiu D7 really shines and Polygon must’ve been listening to our every word when we reviewed the previous model.

Now fitted with a RockShox Recon RL fork that has a 15×100mm axle and 120mm of travel (for both the 650b and 29er bikes), we’re optimistic that the front end won’t be nearly as flexy as on the old model.

Polygon Siskiu

The forks are matched with an X-Fusion O2 Pro RL rear shock that has both externally adjustable rebound and a lockout function.

You’re treated to an 11-speed Shimano XT mech, SLX shifter and a Sunrace 11-speed 11-46t cassette. You also get Shimano’s M201 disc brakes with a 180mm front rotor and 160mm rear.

Polygon Siskiu

The bike’s finishing kit is taken care of by a host of Polygon in-house parts, branded as Entity. There’s a 780mm wide bar, a 45mm stem and XL2 wheelset.

The wheels are wrapped in WTB Trail Boss tyres that, whether in 650b or 29in versions are 2.25in wide.