Polygon Siskiu D5 Lg

The Siskiu D5 is Polygon’s way into real full-suspension mountain biking. It runs 120 mm of travel front and rear on an ALX XC Trail alloy frame, with a tunable air shock, hydraulic disc brakes and a simple Shimano CUES 1×9 drivetrain — the parts that actually matter on a trail, without the parts that only add price.

It is a bike designed to grow with you. Modern trail geometry keeps it steady when the ground gets loose, the rims are tubeless ready for when you want to drop pressure, and the frame uses standard sizing and a threaded bottom bracket, so it stays easy and cheap to service.

Who it is for

Riders moving up from a hardtail, or buying their first proper mountain bike. If you ride Hatta, Showka, Al Qudra’s rougher loops or Mushrif Park and you have started to feel the hardtail bouncing you around, this is the step that fixes it. It is also a sensible choice for a rider who wants one capable bike for weekend trails rather than a specialised race machine.

What you get for the money

A real air shock

The rear shock is an SR Suntour Raidon LO — air-sprung, not a coil. You set the pressure to your own weight, so the bike works the same for a 60 kg rider and a 95 kg one. At this price most bikes give you a coil you cannot adjust.

120 mm front, 120 mm rear

An SR Suntour XCM32 fork with 32 mm stanchions and a hydraulic lockout lever. Flip the lever for road and climbs, open it for the trail. Matched travel front and rear keeps the bike balanced when things get rough.

Shimano CUES, one shifter

A single 32T chainring and a 9-speed 11-46T CUES cassette. One shifter, nothing to cross-chain, nothing to drop — and CUES is Shimano’s current entry platform, so spares are everywhere. Braking is Shimano MT200 hydraulic disc.

Geometry that builds confidence

A slack front end, a 760 mm bar and a short 45 mm stem. The D5 is set up to feel stable when you point it downhill, which is exactly what you want on a first full-suspension bike.

The build at a glance

• Frame — ALX XC Trail 6061 aluminium, one-piece linkage, 120 mm travel, internal cable routing, 141 mm Boost QR, threaded BB
• Fork — SR Suntour XCM32, 120 mm, hydraulic lockout, tapered steerer
• Rear shock — SR Suntour Raidon LO Air, 190×51 mm, air spring with lockout
• Drivetrain — Shimano CUES 1×9: SL-U4000 shifter, RD-U4000 derailleur, CS-LG300 11-46T, 32T chainring
• Brakes — Shimano MT200 hydraulic disc, 180 mm front / 160 mm rear
• Wheels — Polygon MT6 alloy double wall, 23.3 mm internal, tubeless ready, on WTB Trail Boss Comp 27.5×2.25″
• Cockpit — Polygon Sport alloy, 760 mm bar with 20 mm rise, 45 mm stem
• Weight — 16.8 kg (37 lb), size L
• Included — alloy cage pedals with reflectors

Sizing

Polygon builds the Siskiu D5 in S, M and L on 27.5″ wheels. As a rough guide Polygon puts S at 155–168 cm, M at 163–178 cm and L at 173–185 cm. If you are between two sizes, or you are not sure, message us on WhatsApp with your height and inseam or come and sit on one at the shop before you buy.

Specification as published by Polygon and subject to change by the manufacturer without notice.