Why buy your bike from Sigma Sports?
Don't hesitate to reach out to us. It's our goal to answer all of your questions and offer the best advice from our experts. We’ll be happy to answer any questions you may have. Contact us now or visit us in-store.
All our bikes are fully built by our Cytech qualified mechanics. To find out more, see the Built, Checked, Tuned and Tested section below to see how we'll deliver your bike.
We offer FREE DELIVERY of your bike to your home or place of work. Once you've placed your order, our Customer Care team will be in contact to offer a convenient delivery date of your choice.
We've partnered with PedalSure to offer you 30-DAYS FREE bike insurance on new bikes over £400. Visit our Cycle Insurance page to learn more and claim.
Trek Session 8 27.5 GX Mountain Bike 2021
A full suspension, downhill mountain bike, the Trek Session 8 27.5 GX Mountain Bike is built for rugged, off-road trails. An Alpha Platinum Aluminium frame is paired with a RockShox Boxxer Select fork, and the SRAM 7-speed groupset is a fantastic addition. Damping the impact from even the most extreme of jumps, the Fox Performance VAN rear suspension is adjustable and easy to tailor to the intensity of the terrain you are riding.
Truvativ's Descendant DH crankset features a 34T steel chainring and it's paired with an 11-25 cassette, offering smooth and precise shifting. Wheels come courtesy of Bontrager, with their Line DH 30 alloy Tubeless Ready variants combining with Bontrager G4 Team Issue tyres. Bontrager further contributes to this bike with the addition of a Bontrager Line Pro stem, Line handlebar, Rhythm Elite alloy seatpost and Arvada saddle. Finishing touches include Wellgo BO-87B pedals and Bontrager XR Trail Elite grips.
- Trek Alpha Platinum Aluminium frame
- RockShox Boxxer Select fork with 200mm travel
- Fox Performance VAN rear suspension with externally adjustable rebound and low-speed compression
- Mino Link lets you make small adjustments to your geometry quickly and easily, even mid-ride
- 27.5-inch wheels are great for flicking the bike around through the most technical trails
- Bontrager Line handlebar and stem
- Bontrager Arvada saddle
|Frame||Trek Alpha Platinum Aluminium, tapered head tube, internal control routing, integrated frame protection, downtube guard, ISCG 05 mount, magnesium rocker link, Mino Link, ABP, 157x12mm thru-axle, 210mm travel|
|Fork||RockShox Boxxer Select, DebonAir spring, Charger RC damper, 46mm offset, 20x110mm Boost thru-axle, 200mm travel|
|Rear Suspension||Fox Performance VAN, externally adjustable rebound and low-speed compression; (S 400lb; M 450lb; L 500lb; XL 500lb spring), tuned by Trek Suspension Lab, 8.75x2.75"|
|Bottom Bracket||SRAM DUB, 83mm, BSA threaded|
|Stem||Bontrager Line Pro, 35mm, Direct Mount, 50mm length|
|Handlebar||Bontrager Line, alloy, 35mm, 27.5mm rise|
|Grips||Bontrager XR Trail Elite, alloy lock-on|
|Front Brake||SRAM Guide R hydraulic disc|
|Rear Brake||SRAM Guide R hydraulic disc|
|Brake Levers||SRAM Guide R hydraulic disc|
|Rear Derailleur||SRAM GX DH|
|Shift Levers||SRAM GX DH, 7-speed|
|Cassette||SRAM PG-720, 11-25, 7-speed|
|Chain||SRAM PC-1110, 11-speed|
|Crankset||Truvativ Descendant DH, DUB 83, 34-T steel ring|
|Pedals||Wellgo BO-87B, alloy body, Cro-Mo axle, replaceable pins|
|Front Wheel||Bontrager Line DH 30 alloy, 27.5-inch, Tubeless Ready, 6-bolt|
|Rear Wheel||Bontrager Line DH 30 alloy, 27.5-inch, Tubeless Ready, 6-bolt|
|Front Tyre||Bontrager G4 Team Issue, Inner Strength sidewalls, wire bead, 60 tpi, 27.5x2.4"|
|Rear Tyre||Bontrager G4 Team Issue, Inner Strength sidewalls, wire bead, 60 tpi, 27.5x2.4"|
|Saddle||Bontrager Arvada, hollow chromoly rails|
|Seatpost||Bontrager Rhythm Elite alloy, 31.6mm, 0mm offset|
|Manufacturer Claimed Weight||M - 16.27kg / 35.87lbs (with tubes)|
Built, Checked, Tuned and Tested
All our bikes are fully built, checked, tuned and tested by our Cytech qualified mechanics and then securely packaged, ready for delivery. All you have to do is add the pedals (if specified), attach the handlebars to the stem and tighten them following the included detailed instructions or by watching our video and using the provided FREE tools. Visit our Bike Assembly page to see how you assemble your new bike once you receive it.
All bikes collected from our shop, are built, tested and ready to ride.
Please note, occasionally, manufacturers may change the specification without notice. Bicycles do not come with pedals unless otherwise specified. We do not install accessories to bikes, including mudguards.
Trek Session 8 27.5" GX Mountain Bike 2021 Sizing
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