You had to know it was on the horizon. All the posts hinting at new 29″ DH forks and teams testing the wagon wheels in big races were a dead giveaway. Now it looks like Trek is ready to take the plunge into 29er DH territory, though it’s been many years in the making. As far back as the Gary Fisher days, Trek has been playing with long travel 29ers. While the frames proved that the geometries were compatible with the wheel size, they said that the “complementing parts just weren’t there yet.” Â Add a few more prototypes into the mix and before you know it, you arrive at the all new Trek Session 29 – a carbon DH frame that is very similar to the new Session 27.5 Carbon, with the exception of a slight difference in wheel size…
![](https://bikerumor.com/wp-content/uploads/2017/05/Session_29_last_Prototype-e1495727080223-600x341.jpg)
Back in the GF days, the big wheel experiment never made it to the public, though the project proved what was possible. Then it was a 180mm travel frame with a 64.5° head tube angle and 440mm chainstay – numbers that would probably still do pretty well today. After the Gary Fisher brand was phased out, Trek got a hold of the long travel 29 project and started making Session prototypes.
It seems that with the introduction of more DH worthy 29er parts, that Trek is finally ready to release the big wheeled session to the world – though only as a frameset. While complete bikes will be available in 27.5″, the 29″ Session will only be sold as a frame, Float Factory X2 rear shock, and the matching Fox 40 FIT RC2 fork for $4,999. Feature wise, the frame is the same of the 27.5″ version with a few exceptions like geometry and 190mm of travel front and rear to accommodate the bigger wheels.
One of the biggest changes to both wheel size frames comes in the form of the revised suspension design. No longer relying on the Full Floater concept to gain additional tuning from the rear shock, the frame has been designed around the Fox Float X2 air shock with a fixed lower shock mount. Trek claims the improved tune of the X2 allowed them to find the performance they were looking for without the Full Floater mount which in turn made for a stiffer frame. The Session still runs an ABP (Active Braking Pivot) rear end with a 157 x 12mm thru axle for both sizes for suppleness under braking. Rear suspension has also been tuned to provide a more lively ride through progressive valving in the shock, a lower leverage ratio, and longer shock stroke. Not a fan of air shocks? The Session can still run a Metric coil shock as well.
A high degree of adjustability has been built into the frame with Trek’s Mino Link and an adjustable headset system. Through the Mino Link, the head tube angle can be adjusted by 1/2°, and the bottom bracket height varies by 7mm. To add further adjustability, the frame ships with flat headset cups as well as two fixed angle cups as well. The standard 56/49mm cups are offset by 1° allowing for 1° of headset adjustment in either direction for a total range of 62.1-64.4°.
Additional improvements have been made to increase the frame’s stiffness as well as tune the geometry to be more aggressive – this is a race bike after all. Featuring a 20mm longer reach, 10mm lower bottom bracket and 63° stock head tube angle, the bike is all about aggressive World Cup level riding, though park rats should still be able to find their happy spot by going down a size. Or, there’s always the aluminum Session which hasn’t changed like the carbon Session.
As you’d expect, the Session OCLV Carbon frames include details like Carbon Armor for the downtube, chainstays, and seatstays, ControlFreak internal cable routing, and integrated fork bumpers – all of which is the same for the 27.5 and 29″ Session. Trek says that ultimately the 29″ Session will be for riders looking for every advantage when it comes to speed as well as those who are ok being early adopters. Otherwise, the 27.5″ Session will still be the go to for the remaining 90% of the market.
The Session 27.5″ Carbon will be available as both a frameset (no fork for the 27.5″ version) for $3,999, or as a complete Session 9.9 27.5 RSL for $7,999. Expect availability on both the 27.5 and 29″ version this fall.