Trek has been refining the Session for a few years now and for 2015 they’re offering it with 27.5 / 650b wheels. Piloted and refined by the Trek World Racing team, this new big wheel’d Session has evolved. Inside we review some of the details on the carbon 2015 Trek Session 9.9 DH 27.5.
Last year we took a look at Neko Mulally’s team issue Trek Session (pictured above) and many of those features and changes carried over into the production Trek Session 9.9 DH 27.5 that you can see more of below. The decals and Shimano logo are all clear coated over as well for a clean professional look.
MSRP: $9,349.99 USD Complete
World Cup ready: 27.5″ wheels, longer wheelbase, 210mm travel
OCLV Mountain Carbon with Carbon Armor is downhill tough
ABP keeps your suspension active while you’re on the brakes
Mino Link adjustable geometry lets you fine tune your ride
We have a robust weight section on SickLines and you can see some of the key weights for the 2015 Trek Session 9.9 DH below.
Trek has been making carbon fiber bikes for quite some time. With their OCLV carbon fiber experience Trek has developed a bike that is quite lightweight and strong. Building up a lightweight Session isn’t hard when you consider how light the frame is already.
The pivot hardware on the Session 9.9 is designed well. It allows for easy torquing as all of the bolts are readily accessible even with all the parts installed. The captive nuts sit inside the frame so the bolts can easily be secured from the non drive side for almost all of the bolts. This is handy should you need to remove, check bolt torque, or when building one up.
We’re fans of conventional threaded bottom brackets on downhill bikes and Trek is too apparently. The 83mm bottom bracket shell and ISCG-05 chainguide tabs make it easy to install the necessary parts on.
The rubberized downtube guard is adhesively secured and sits near the bottom of the downtube. It doesn’t extend down the full length of the downtube behind the bottom bracket but it does get close. It would’ve been nice to see it extend all the way down in this area.
Trek’s Active Braking Pivot DH (ABP) was setup for a 157x12mm rear wheel that helps the hub slot into the frame. Trek claims this is 20% stiffer than an open dropout design. The ABP DH is also convertible to run 150x12mm wheels.
The Session 9.9 DH frame has adjustable mino chips that gives the session two geometry settings for you to pick from.
The tapered carbon fiber E2 headset is pretty clean. Trek prides itself on its carbon fiber process and its clear why.
The Session 9.9 DH frame has internal cable routing in the frame. They’ve cleverly designed the integrated fork bumpers to hide the cables. If you want to run cables externally as well that is an option although not as elegant.
Trek includes a lot of neat extras as well including
A Sag Tool that connects to the linkage (pictured below, more photos in the gallery)
Included with the DT Swiss FR 1950 wheelset are tubeless valve cores. Equipping the DT wheelset with higher engagement is easily upgraded to 36 points of engagement versus the stock 18 by purchasing DT’s 36point star ratchets.
The chainstay guard holds the rear derailleur cable. It’s a clean design for a factory look but means its mandatory unless you fabricate something else.
To keep things lightweight, Trek uses some oversized axles and bolts. The shock bolts for example are large aluminum bolts. These oversized aluminum shock allen bolts take an 8mm wrench to install versus a 5mm or 6mm allen wrench.
To accommodate the aluminum hardware, the 8.75″ x 2.75″ shock uses oversized hardware. The lower eyelet’s hardware utilizes offset hardware to center the shock properly on the frame. Since the shock hardware is wide here, you’ll have to remove it if you need to try other spring rates as the spring can’t be removed without removing the lower hardware.
We’ve taken a lot of detailed pictures of the 2015 Trek Session that you can see more of below if you’re in the market for one of these gorgeous bikes. Trek has done an impressive job with this bike from a design and construction standpoint.
Trek also offers the Session in four models for 2015. While this is the top of the line model, there is also a Session 9.8 Park 26, Session 88 DH 27.5, and a Session 8 Park 26. Learn more about the 2015 Trek Session models at www.trek.com