If you were making the rounds out at the second day of Outdoor Demo, you would have had the chance to catch World Cup Champion Aaron Gwin signing autographs in front of the Trek and Shimano tents. Sitting right next to Gwin was the latest iteration of his Trek Session 9.9 DH weapon. While most people were glancing right over it, a closer look would reveal a few interesting parts that may signal a new DH group from Shimano in the near future. Shimano has been completely mum on the subject, but they weren’t too concerned about having the bike right out in the open.

Check out the Shimano trickery after the break!


Once you got past the bitchin’ America paint job and Gamut bash guard, my eyes naturally gravitated towards the rear derailleur. There is no hiding the fact that it is an XTR Shadow Plus equipped derailleur, but it is also one of the few short cage models likely in existence. In addition it appears that the area around the B-Tension assembly has been beefed up compared with the standard XTR model. All of which further suggess that this may be more than just a short cage XTR derailleur, and may lead to a new DH spec down the road.


The perfect DH rear der?





Now about the brakes. It’s fairly public knowledge that for some time Gwin has been riding a set of custom Shimano brakes that consisted of a stock Saint caliper attached to an XTR trail lever. The brakes that are currently on Gwin’s rig may look extremely similar to his prior setup (minus graphics) but there are key differences if you look hard enough.


Visible differences to the caliper include the fairly obvious top loading brake pads, which follow in the steps of the newly revised XT and XTR disc brakes. Also, the previous Saint caliper was a two piece design which was held together by 4 different bolts. This “mystery” caliper is still a two piece design, but it loses two bolts along the way.



Levers remain largely unchanged from the XTR Trail levers Gwin was running, save for the new lever design. No word on whether this is just a personal customization for Gwin, or if this is something that may see production, but the new lever does seem more likely to hold up in a crash – especially on a DH bike. Note that the lever still features tool-less reach adjustment and the adjustment screw for free stroke.



  1. C’mon Shimano make short cage available in all your derailleurs. Until that happens I am sticking with SRAM. I will admit that Shimano’s shifting actually seems little nicer than SRAM when it comes to the ten speed stuff. Can’t say the same for the 9 speed though.

  2. Gwinny and Moseley were in the Trek Store Colorado in Boulder, CO in July with both of their bikes. I talked to Gwinny about the XTR and he said the Derailleur wasn’t the best part, it was the prototype shifters. They were completely redesigned and were capable of shifting up (harder gear) twice with one throw of the lever. It has two clicks and shifted up really well. It of course had the standard capability of shifting down (easier gear) three times with a full throw of the shifter. It was super impressive to click back and forth.

  3. Its good he’s got Monk doing his wrenching. That guys has a lot of experience and even more experience working with prototype weirdness.

What do you think?