New Trek Session, now with big wheels
Originally posted on May 25, 2017 at 10:30 amTwo wheel size choices, and stiffer, stronger, lighter. The Session is all new and ready to continue winning World Cups.
The new Session gets longer, lower, stiffer and more adjustable, which is what all updated bikes seem to do these days. The real news is a frameset option for 29 inch wheels.
When you have one of the winningest downhill racers (and her brothers) riding for you, it is imperative to stay at the forefront of go-fast technology. Although can you really call a wheel size that is now at least 18 years old the forefront of anything?
All that aside, the big wheels seem to be set to take over the downhill racing scene, and perhaps further separate the park bikes from the racing bikes, in a similar fashion to the separation between cross-country race bikes and trail bikes.
From Trek:
The world’s fastest downhill race bike gets even faster.
Forged by the brutal demands of the World Cup circuit, all-new Session 9.9 turns up the speed with a stiffer frame, race-focused geometry, and a livelier ride with an updated suspension design optimized for air shocks. While the complete bike sports ever-popular 27.5” wheels for all-around performance on any track, we’re also offering something special for riders who always want more.
For more speed, we’re offering all the benefits of new Session on a 29er chassis. Offered in limited quantity as a frame & fork package, Session 29 brings faster-rolling big wheels to the downhill scene.
Trek has been missing around with big wheels longer than any other major player, starting way back when Gary Fisher still had his own brand. In 2008 Trek built up this 29er DH test mule:
And more recently, this bike was making the rounds:
In final form, we’ll get this:
Much like the recently announced Santa Cruz V10 29er, Trek uses the same OCLV carbon front triangle for both wheel sizes, with separate linkages and swingarms for each.
| MODEL | US | AVAILABILITY | |
| Session 8 27.5 | 3,999.99 | Now | |
| Session 9.9 27.5 RSL | 7,999.99 | September | |
| Session Alloy 27.5 frameset | 2,099.99 | Now | |
| Session Carbon 27.5 frameset | 3,999.99 | August | |
| Session Carbon 29 frameset* | 4,999.99 | October | |
| *Session 29 frameset includes FOX fork as well as frame and shock | |||
The Session 8 is the same aluminum frame from last year, no geo changes or 29-inch option.
The new bikes are designed around the spring curve of an air shock, although a coil shock can be fitted. Geometry is easily adjustable. The Mino link chip can drop the head angle a half-degree and the bottom bracket 8 mm. The bikes will include a set of 1 degree offset headset cups to further adjust head angle by a full degree in either direction. Geometry is at the end of this post.
The Full Floater shock linkage is gone. Trek claims improvements in air shock tuning and adjustability negated the need for the floating shock linkage. Eliminating this linkage allowed Trek to drop a bit of weight while making the frame stiffer and stronger.
Since the big wheels were the worst kept secret on the downhill circuit this year, the new Session 29 doesn’t feel as groundbreaking as one would expect. It should be an interesting season for professional downhill. With talk of seconds saved on sub-five minute courses, 29 inch wheels might be enough of an advantage to shuffle some podium positions. Check out Trek’s website for more info, and tune into the Fort William coverage on Redbull to see the big wheels put to the test.
| Session 27.5 Carbon | ||||||||
| Frame Size | Small | Small | Medium | Medium | Large | Large | Extra Large | Extra Large |
| Mino Link Position | Low | High | Low | High | Low | High | Low | High |
| Size Wheel | 27.5″ | 27.5″ | 27.5″ | 27.5″ | 27.5″ | 27.5″ | 27.5″ | 27.5″ |
| Seattube | 42.5 | 42.5 | 42.5 | 42.5 | 45.6 | 45.6 | 45.6 | 45.6 |
| Angle Eff Seattube | 74 | 74.5 | 74 | 74.5 | 74 | 74.5 | 74 | 74.5 |
| Angle Seattube | 57.5 | 58 | 57.5 | 58 | 57.5 | 58 | 57.5 | 58 |
| Length Headtube | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 |
| Angle Head | 63 | 63.5 | 63 | 63.5 | 63 | 63.5 | 63 | 63.5 |
| Eff Toptube | 58.1 | 57.9 | 60 | 58.4 | 62.1 | 60.6 | 64.6 | 63.1 |
| BBHeight | 34.9 | 35.6 | 34.9 | 35.6 | 34.9 | 35.6 | 34.9 | 35.6 |
| BBDrop | 8.5 | 2 | 8.5 | 2 | 8.5 | 2 | 8.5 | 2 |
| Length Chainstay | 44.6 | 44.5 | 44.6 | 44.5 | 44.6 | 44.5 | 44.6 | 44.5 |
| Offset | 5.2 | 5.2 | 5.2 | 5.2 | 5.2 | 5.2 | 5.2 | 5.2 |
| Trail | 12.4 | 12 | 12.4 | 12 | 12.4 | 12 | 12.4 | 12 |
| Wheelbase | 121.7 | 121.6 | 123.6 | 123.5 | 125.7 | 125.6 | 128.2 | 128.1 |
| Standover | 73.2 | 73.8 | 73.3 | 43.9 | 74 | 74.6 | 74.2 | 74.8 |
| Frame Reach | 40.5 | 41 | 42.4 | 42.9 | 44.5 | 45 | 47 | 47.5 |
| Frame Rise | 61.9 | 61.6 | 61.9 | 61.6 | 61.9 | 61.6 | 61.9 | 61.6 |
| Frame Stack | 61.9 | 61.6 | 61.9 | 61.6 | 61.9 | 61.6 | 61.9 | 61.6 |
| Session 29 Carbon | ||||||||
| Frame Size | Small | Small | Medium | Medium | Large | Large | Extra Large | Extra Large |
| Mino Link Position | Low | High | Low | High | Low | High | Low | High |
| Size Wheel | 29″ | 29″ | 29″ | 29″ | 29″ | 29″ | 29″ | 29″ |
| Seattube | 42.5 | 42.5 | 42.5 | 42.5 | 45.6 | 45.6 | 45.6 | 45.6 |
| Angle Eff Seattube | 73.1 | 73.6 | 73.1 | 73.6 | 73.1 | 73.6 | 73.1 | 73.6 |
| Angle Seattube | 56.6 | 57.1 | 56.6 | 57.1 | 56.6 | 57.1 | 56.6 | 57.1 |
| Length Headtube | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 |
| Angle Head | 62.1 | 62.6 | 62.1 | 62.6 | 62.1 | 62.6 | 62.1 | 62.6 |
| Eff Toptube | 58.3 | 58.2 | 60.2 | 60.1 | 62.3 | 62.2 | 64.8 | 64.7 |
| BBHeight | 35 | 35.6 | 35 | 35.6 | 35 | 35.6 | 35 | 35.6 |
| BBDrop | 22.5 | 16 | 22.5 | 16 | 22.5 | 16 | 22.5 | 16 |
| Length Chainstay | 45 | 44.9 | 45 | 44.9 | 45 | 44.9 | 45 | 44.9 |
| Offset | 5.8 | 5.8 | 5.8 | 5.8 | 5.8 | 5.8 | 5.8 | 5.8 |
| Trail | 13.1 | 12.8 | 13.1 | 12.8 | 13.1 | 12.8 | 13.1 | 12.8 |
| Wheelbase | 122.6 | 122.5 | 124.5 | 124.4 | 126.6 | 126.5 | 129.1 | 129 |
| Standover | 73.5 | 74.1 | 73.6 | 74.2 | 74.3 | 74.9 | 74.5 | 75.1 |
| Frame Reach | 39.6 | 40.1 | 41.5 | 41.9 | 43.6 | 44 | 46.1 | 46.5 |
| Frame Rise | 61.9 | 61.6 | 61.9 | 61.6 | 61.9 | 61.6 | 61.9 | 61.6 |
| Frame Stack | 61.9 | 61.6 | 61.9 | 61.6 | 61.9 | 61.6 | 61.9 | 61.6 |