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.
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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.
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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.
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The bike uses size-specific wheels: the smaller 15.5” frame has 650b hoops while the 17in frame can be used with either 650b or 29in wheels. The larger bikes — 19in and 20.5in 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 19in, 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
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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.
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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.
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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.
Polygon Siskiu D7 pricing and availability
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The Siskiu D7 costs €1,299 but there’s an even lower-priced D5 that has a lower spec — a 9-speed Shimano Alivio drivetrain and Suntour fork and shock — that costs €899.
The bikes are available to buy direct from Polygon’s website, now.