Interbike 2012: FSA Brings BB386EVO to Mountain Bikes, Debuts Gradient Carbon Trail Group!
FSA’s new Gradient line falls under the Gravity segment. It’s a bridge between the SL-K and the full on Gravity parts, aimed at the 6″ trail bikes.
The Gradient MegaEvo crankset comes spec’d with their new D10 chainrings in a 36/24 double layout that’s compatible with SRAM and Shimano front derailleurs. The new rings are moved outboard a bit to improve SRAM compatibility.
They’re shown with a new bash guard that’ll fit 36 and 38 tooth big rings. They’re working on a smaller one, too. Outside is clean with comolded inserts that use chainring bolts to hold it on from the inside.
More on the group and other bits below, plus details on how they’re taking the BB386EVO road standard to the dirt…
The cranks are UD carbon fiber and get removable rubber endcaps. They’re also the first mountain bike crankset to get the 30mm Evo spindle. Like their BB386EVO road cranks, it’ll work with BSA threaded bottom brackets as well as BB30 and PFBB30.
When BB386EVO was introduced, we asked if it would port to mountain bikes and the answer was no. Why? Because the 86mm wide BB shell wouldn’t allow for the smaller chainrings typically used off road.
The solution is that this spindle is 5mm wider that the road versions, so it’ll fit in a standard BSA setup because the external BB cups provide the necessary space between the frame and the small ring. For BB30/PFBB30, you’ll simply put 8.5mm spacer in either side for a 73mm BB shells and 11mm spacer on 68mm BB shells. For most trail bikes, though, you’re probably looking at frames with a BSA setup and won’t need all those spacers. Keep reading at the bottom of the post to see where this is headed.
The Gradient cranks come in 165, 170 and 175 lengths with a 104BCD. Weight is 845g with chainrings and bashguard (170). The bashguard alone is 158g, so remove that and you have a very competitive weight. It’ll come with the bashguard and work as a double or triple.
The carbon arms are molded as an inner carbon tube first, which give them fine control over the layup and wall thickness. Then the pedal thread inserts are bonded in at room temperature after construction, which eliminates any contraction or expansion that could cause things to come loose down the trail. They’re fairly straight, necessary because of the wider spindle, and engineer Jason Miles says this also lets them make it lighter and stronger.
The Gradient line includes two handlebars and a 400mm long seatpost. All use a CSI (Carbon Structural Integration), which is an alloy base wrapped in carbon. The benefit is a mix of strength and weight savings and they’ll bend rather than snap if you take a hard landing.
Bars are both 777mm wide and have 10° backsweep and 4° upsweep with 0 ad 15mm rise options. Weights are 336g.
Post is 0mm setback with all three common diameters at 400mm long. 240g.
Gravity Light Lock On Grips have a tapered edge to be super thin and have color matched anodized lock rings. 140mm wide, 114g.
On their more performance oriented lines like SLK and K-Force Light, their placards showed 386 as an option. Their reps said those cranksets will come online as 2014 products, but given the likelihood of PFBB30 frames on the bikes these cranksets will show up on, we’re hoping they come up with a more elegant spacing solution. That, or we’re going to start seeing some pretty interesting frame designs!