Size Guide
Description
Specifications
Geometry
Size Guide
Assembly
REFINED FOR MORE
The revamped Siskiu T adds UDH compatibility, a reinforced rear triangle, and improved internal cable routing for a sleek, future-proof build. A discreet top-tube mount adds utility, while progressive suspension with a larger volume spacer smooths big hits. A 0.5° slacker head tube, slightly steeper seat tube, and longer reach improve stability and climbing balance without changing the familiar Siskiu ride feel.
ULTIMATE VALUE
Built for riders chasing real trail performance: FOX 34 Rhythm fork and Float DPS Performance shock deliver responsive, balanced suspension, Shimano SLX 12-speed drivetrain ensures crisp, reliable shifting, and a Manic dropper post keeps you in control. Shimano 4-piston brakes and Maxxis Dissector EXO+ tyres complete a performance-focused build.
ANY TRAIL, ANY RIDER
The Siskiu T is Polygon's do-it-all trail bike for riders of all levels. From flowy singletrack to technical features, this bike is designed to conquer any trail you encounter. With a lightweight alloy frame, 135mm of rear travel, and 29er wheels, it's both nimble and stable, providing a comfortable and confidence-inspiring ride.
INDUSTRY REVIEW
“The changes made to the 2026 Polygon Siskiu T8 certainly fall into the ‘upgrade’ category in our minds… it is impressive to see that Polygon was able to accommodate those upgrades while somehow lowering the price. The frame still looks sharp and continues to stand out in its category.” - The Loam Wolf
FOX 34 FLOAT RHYTHM
The latest FOX 34 Float Rhythm features a stiffer, more precise chassis and refined internals, giving you the confidence to push harder on every trail. Its plush 140 mm FLOAT EVOL air spring delivers improved small-bump sensitivity, while the proven GRIP damper keeps control buttery-smooth from flowy singletrack to chunky rock gardens.
FOX FLOAT DPS PERFORMANCE
This shock combines a larger-volume EVOL air spring with refined dual-piston damping for smoother small-bump feel, better support, and consistent control. A new main piston, valving, and Internal Floating Piston boost performance and tuneability, while the one-piece EVOL sleeve and bottom-out bumper improve responsiveness and add end-stroke progressivity for confident finishes.
SHIMANO SLX/DEORE & BR-MT420
Reliable and precise, Shimano SLX/Deore 1×12 drivetrain features a wide-range 10–51T MicroSpline cassette with Hyperglide+ technology, delivering smooth shifting up or down the cassette even under heavy pedalling load. Powerful BR-MT420 4-piston brakes provide impressive stopping power, excellent modulation, and proven reliability.
IMPROVED WHEELS & MAXXIS
Over 200 g lighter, this reengineered wheelset features a reinforced nipple channel and offset spoke lacing for balanced tension, paired with upgraded Sapim stainless spokes. A hookless rim bead shrugs off impact damage, while a destressed, hand-retention build helps the wheels stay true ride after ride. Paired with grippy Maxxis Dissector tyres, it delivers speed, strength, and confident handling when trails get technical.
X‑FUSION MANIC
Confidence on every descent is just a lever-press away. The internally routed Manic LC dropper offers smooth travel that can be stopped at any position within its set range, letting you quickly get the saddle out of the way. Paired with a new composite lever for lighter, stiffer actuation, its low stack height and micro-adjust clamp maximise fit, keeping you in control.
We reserve the right to modify product specifications and details without prior notification.
Length measurements are provided in millimeters and degrees, unless specified otherwise.
If you are outside of the size range or unsure of the best fit, give us a call and we'll help get you on the right bike.
| Size | Age | Range (cm) | Range (ft & in) |
|---|---|---|---|
| 12" (Balance) | 2 - 4 | 80 - 100 | 2'6" - 3'1" |
| 16" | 4 - 7 | 100 - 120 | 3'4" - 4'0" |
| 20" | 7 - 9 | 120 - 135 | 4'0" - 4'5" |
| 24" | 9 - 11 | 135 - 145 | 4'5" - 4'9" |
If you are outside of the size range or unsure of the right fit for you, give us a call or come in and visit your local store to talk about your best options.
Explore our series of how-to video guides designed to walk you through every stage of assembling and fine-tuning your new Polygon Siskiu T8 - Mountain Bike MY26. Whether you watch the entire series or focus on specific tasks, we've got you covered. Our dedicated Customer Service team is here to offer expert advice and ensure your bike is ready for the road.
Planning to assemble at home? Remember to install the pedals with care. Make sure to align them square and gently tighten to avoid stripping the threads.
Description
REFINED FOR MORE
The revamped Siskiu T adds UDH compatibility, a reinforced rear triangle, and improved internal cable routing for a sleek, future-proof build. A discreet top-tube mount adds utility, while progressive suspension with a larger volume spacer smooths big hits. A 0.5° slacker head tube, slightly steeper seat tube, and longer reach improve stability and climbing balance without changing the familiar Siskiu ride feel.
ULTIMATE VALUE
Built for riders chasing real trail performance: FOX 34 Rhythm fork and Float DPS Performance shock deliver responsive, balanced suspension, Shimano SLX 12-speed drivetrain ensures crisp, reliable shifting, and a Manic dropper post keeps you in control. Shimano 4-piston brakes and Maxxis Dissector EXO+ tyres complete a performance-focused build.
ANY TRAIL, ANY RIDER
The Siskiu T is Polygon's do-it-all trail bike for riders of all levels. From flowy singletrack to technical features, this bike is designed to conquer any trail you encounter. With a lightweight alloy frame, 135mm of rear travel, and 29er wheels, it's both nimble and stable, providing a comfortable and confidence-inspiring ride.
INDUSTRY REVIEW
“The changes made to the 2026 Polygon Siskiu T8 certainly fall into the ‘upgrade’ category in our minds… it is impressive to see that Polygon was able to accommodate those upgrades while somehow lowering the price. The frame still looks sharp and continues to stand out in its category.” - The Loam Wolf
FOX 34 FLOAT RHYTHM
The latest FOX 34 Float Rhythm features a stiffer, more precise chassis and refined internals, giving you the confidence to push harder on every trail. Its plush 140 mm FLOAT EVOL air spring delivers improved small-bump sensitivity, while the proven GRIP damper keeps control buttery-smooth from flowy singletrack to chunky rock gardens.
FOX FLOAT DPS PERFORMANCE
This shock combines a larger-volume EVOL air spring with refined dual-piston damping for smoother small-bump feel, better support, and consistent control. A new main piston, valving, and Internal Floating Piston boost performance and tuneability, while the one-piece EVOL sleeve and bottom-out bumper improve responsiveness and add end-stroke progressivity for confident finishes.
SHIMANO SLX/DEORE & BR-MT420
Reliable and precise, Shimano SLX/Deore 1×12 drivetrain features a wide-range 10–51T MicroSpline cassette with Hyperglide+ technology, delivering smooth shifting up or down the cassette even under heavy pedalling load. Powerful BR-MT420 4-piston brakes provide impressive stopping power, excellent modulation, and proven reliability.
IMPROVED WHEELS & MAXXIS
Over 200 g lighter, this reengineered wheelset features a reinforced nipple channel and offset spoke lacing for balanced tension, paired with upgraded Sapim stainless spokes. A hookless rim bead shrugs off impact damage, while a destressed, hand-retention build helps the wheels stay true ride after ride. Paired with grippy Maxxis Dissector tyres, it delivers speed, strength, and confident handling when trails get technical.
X‑FUSION MANIC
Confidence on every descent is just a lever-press away. The internally routed Manic LC dropper offers smooth travel that can be stopped at any position within its set range, letting you quickly get the saddle out of the way. Paired with a new composite lever for lighter, stiffer actuation, its low stack height and micro-adjust clamp maximise fit, keeping you in control.
Specifications
We reserve the right to modify product specifications and details without prior notification.
Geometry
Length measurements are provided in millimeters and degrees, unless specified otherwise.
Size Guide
If you are outside of the size range or unsure of the best fit, give us a call and we'll help get you on the right bike.
Assembly
Explore our series of how-to video guides designed to walk you through every stage of assembling and fine-tuning your new Polygon Siskiu T8 - Mountain Bike MY26. Whether you watch the entire series or focus on specific tasks, we've got you covered. Our dedicated Customer Service team is here to offer expert advice and ensure your bike is ready for the road.
Planning to assemble at home? Remember to install the pedals with care. Make sure to align them square and gently tighten to avoid stripping the threads.
Our Polygon Siskiu T8 - Mountain Bike MY26 includes the industry-leading Reid Warranty: lifetime on frame/rigid forks and 2 years on non-consumable parts. Shop online to enjoy a 30 Day Test Ride to guarantee you get a great deal.
Home Delivery
Our bikes are shipped in a box 85% assembled and require basic assembly, like turning handlebars and inserting pedals. Check out our Assembly Videos that give instructions on how to do this.
Buy One, Plant One
Since January 2020 we have worked with not-for-profit reforestation partners to donate enough money to pay a local person a fair wage to grow, plant and guard to maturity 1 native tree for every bike we sell.
We've now planted more than 400,000 trees and counting!
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