One of the most common questions we receive at BikesOnline is whether you should buy the Polygon Siskiu D7 or Siskiu T7. On paper they share similar frames, 29-inch wheels and respectable components, but out on the trail they serve very different riders. Over two days of back-to-back testing I set out to discover which bike excels on which terrain and who each model is for.

Rear and fork travel: The D7 has 120 mm of rear travel matched to a 120 mmRockShox Recon Silver RL fork [1]. The T7 increases rear travel to 135 mm and uses a 140 mmfork, giving more cushion for bigger hits [2]. Extra travel increases stability and confidence onrough descents but adds weight and can mute the bike’s lively feel.

Geometry: A head tube angle of about 67° on the D7 keeps steering quick and makes it easy tothread through tight trees [1]. The T7’s slacker ≈ 65.8° head angle lengthens the wheelbase forstability at speed [2]. The D7’s effective seat tube angle between 75.5° and 76° and slightlylonger chainstays (432–436 mm) help keep your weight forward for efficient climbing [1]. TheT7 shortens the chainstays to 430 mm, making it easier to lift the front wheel for manuals andjumps [2].

Drivetrain and components: The D7 uses a Shimano 1×11 drivetrain, while the T7 upgrades toa 1×12 Shimano SLX setup, offering a wider gear range for steep climbs [2]. Both bikes comewith a dropper post so you can quickly adjust saddle height on the fly [1]. The D7 is lighter an

Riding the D7, I immediately appreciated its lively character. The shorter travel and steeperseat angle encourage you to spin up climbs, and the 67° head angle delivers nimble steeringwhen snaking through singletrack [1]. However, on rough, high-speed sections I felt the limitsof the 120 mm suspension sooner and had to pick smoother lines.Switching to the T7, the extra travel and slacker geometry were immediately noticeable [2]. Thebike ploughed through roots and rocks with confidence, and the longer wheelbase kept it stableat speed. The downside was slightly more effort on climbs and in tight corners, and the heavier1×12 drivetrain added some weight. For aggressive riders who prioritise descending, though, thetrade-off is worth it.

Choose the Siskiu D7 if you enjoy long days in the saddle, XC loops and smoother singletrack.Its efficient pedalling and lively handling make it versatile and more budget-friendly [1].Choose the Siskiu T7 if you love hitting technical descents, jumps and rougher trails. The extratravel, slacker head angle and 12-speed drivetrain give you confidence and control ondemanding terrain [2].