A 27.5″ / 29″ aluminum frame full suspension enduro bike with upper mid-range components. Compare the full range
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Based on frame geometry and build specs. Learn more →
A bike with lower gearing will be easier to ride up steep hills, while a higher top end means it will pedal faster down hills. Learn more
used for climbing
used for descending and sprinting
4'11" – 5'5"
5'3" – 5'9"
5'7" – 6'1"
5'11" – 6'5"
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The Polygon Siskiu T8 is a 135mm, 29er that outshines it's $2,600 price tag and was a tester favorite during our recent Budget Bike Round Up.
4 piston brakes
Tektro Brake Levers
Requires precise shock settings
Jan 2023 · Alan Muldoon
The Polygon Siskiu is a hard hitting 29er trail bike with 135mm of travel and a 140mm fork. Dig a little deeper however, and you quickly discover that this isn’t your typical entry-level full suspension bike that’s been dumbed down for mass production. In fact, it’s one of the best budget mountain bikes out there. Best mountain bikes: the ultimate trail, enduro and XC bikes Need to know: Fox 34 fork and Float DPS shock deliver 140mm and 135mm of travel respectively Polygon offers four frame size with a generous 496mm reach on the XL Shimano SLX 12 speed derailleur, shifter and cassette, but with a KMC chain The in-house Entity components are all top quality. The Siskiu gets a relatively slack 65.8º head angle for a stable steering response, ultra-short 430mm chainstays to make it easier to loft the front end, and generous reach measurements across the four frame sizes to guarantee a good fit. And while lots of brands make a big song and dance about custom sizing, but fail to provide short enough seat tubes with adequate dropper post insertion to make it possible to upsize, Polygon has nailed it on the Siskiu T8. With the 430mm seat tube we could comfortably ride the XL bike with the 170mm dropper with room to upgrade to a 200mm post if needed. Detailing on the Siskiu frame is also first rate, from the copper highlights under the seat collar that matches the logo on the underside of the downtube, to the one-piece rocker link that adds frame stiffness while maintaining a minimalist, clean look. Even the bespoke chainstay protection looks fitting for a more expensive bike. Cable routing on the Siskiu is internal on the front triangle, and thanks to tighter sealing on the entry and exit ports for the cables, there was no noticeable rattle. That’s not to say the Siskiu was a silent runner, however. The large loop of brake hose that’s necessary to prevent it from kinking as it exits the rear brake calliper has a tendency to touch the spokes of the rear wheel after the suspension has been compressed, so it can sound like you have a stick stuck in the swingarm. Suspension Getting Fox suspension on a £2k trail bike is quite a boon. And while the 140mm travel Fox 34 Rhythm fork isn’t quite as stout as the 35mm chassis on the RockShox equipped Jamis Faultline, an equivalently-priced bike, it’s only 1mm smaller, so nothing to write home about. The Fox 34 feels responsive and supple off the top, and with a good degree of ramp up it doesn’t bottom too easily on bigger hits. We measured the rear travel on the Siskiu frame at 136mm, so clearly there’s no rounding up here. The single pivot suspension design is controlled by an inline Fox Float DPS shock. It offers a really usable range of rebound adjustment that will comfortably cover a wide variety of rider weights. Using all of the travel doesn’t …Continue reading »
Progressive sizing and geometry, great value for money
Needs a Shimano chain
Jan 2023 · Luke Marshall
When it comes to bang for buck, the Siskiu T7 29 has to be one of the most impressive bikes out there
Geometry is on point for trail riding
Frame is future-proof and ready for upgrades
Decent tyres for getting rowdy
Brakes are component weak link
Great for thrashing rather than mile munching
Sep 2022 · Jeremy Benson
The Polygon Siskiu T8 is an excellent mid-travel trail bike offered at a reasonable price. Polygon's consumer-direct sales model helps keep it affordable...
Awesome build for the price
Apr 2022 · James Smurthwaite
Polygon's race team has been spotted at Sea Otter on a new enduro bike that is due to replace the current Siskiu N9..
Dec 2021 · Ryan Palmer
Possibly the best $2,500 bike we've ever ridden.
Fully capable, modern trail bike geometry
Excellent parts spec for the price
Internal cable routing
Resin-only brake rotors create weak braking
Suspension platform isn't very sophisticated
Oct 2021 · Kelly Jorgensen
An affordable full suspension 24" kids mountain bike? The Polygon Siskiu D24 is a perfect blend of price and performance. Read the review!
Polygon's updated Siskiu T is proof that you don't have to spend the earth to get a very capable trail bike. Featuring on-trend geometry, a robust build kit and a host of improvements over the old model, the Siskiu T8 will have you questioning why you'd need to spend any more.
Exceptionally capable package for the money
Grippy high-volume rubber
Supple & supportive suspension
Sporty handling for a tough trail bike
Handlebars need more sweep
Brakes aren't hugely powerful
The wheels ain't light
BB Standard: BSA, 73mm, Threaded
Color: Radiant Purple - Black
FOX 34 RHYTHM 150mm (27.5") / 140mm (29") TRAVEL
Spring Type: Air
FOX FLOAT DPS SPECIAL TUNING E2E:210X55MM, HARDWARE:8MMX25MM
SHIMANO 2-PIECE CRANKSET BSA THREADED
ZERO STACK (ZS) SEALED BEARING FOR TAPER HEAD TUBE, ZS 44/28.6 | ZS 56/40
Entity Xpert, Alloy, 35mm
ENTITY XPERT, ALLOY W:780MM R:20MM BB:35MM
TRANZ-X 150MM (S-M) 170 (L-XL) TRAVEL, ZERO OFFSET, 30.9MM
ALLOY FLAT PEDAL W / REPLACEABLE PIN & REFLECTOR
Polygon Lock On
SHIMANO SLX RD-M7100-SGS DIRECT ATTACH
SHIMANO MT-510-1 BOOST 32T
SHIMANO SLX SL-M7100-R, 1x12-SPEED TRIGGER
12 SPEED 11-51T
KMC X12 12SPEED
TEKTRO HD-M745 4-PISTONS HYDRAULIC DISC BRAKES
584 / 622-35 32H FOR TYRE 584 / 622-54/76 TUBELESS READY
Novatech D91SB-CL, Thru Axle 15x110mm 32h, Center Lock
Novatec D462SB, 12x148mm 32h, Center Lock
PERFORMANCE TIRE, 27.5”X2.40” / 29”X2.40”
SHIMANO SM-RT54 180mm CENTER-LOCK