Last week, we got word from Chris Cocalis about the new BB386EVO collaboration between BH and FSA, with a promise that all the details would be provided at Sea Otter and shown on their new bike.
The bike in question is the new 2012 BH Ultralight, a 747g frame that uses the new BB386EVO bottom bracket standard to great effect, saving weight and increasing stiffness. Before we can get to the bike, though, we need to run through the new BB standard and what it means for you and the future of road bikes. Click ‘more’ for the full technical rundown and see how they built up a 10.66lb Ultralight using (mostly) regular parts…
BB386EVO – The Future of Road Bottom Brackets?
Before you groan about another standard, let me explain it and, like me, you’ll probably click away thinking this is actually a really good idea. Here’s the deal, in convenient bullet point form:
- Current road BB shell width is 68mm.
- BB30 and PFBB30 systems have a 30mm spindle diameter and set the bearings inside the frame with the outer edge remaining at 68mm, so the crankset spindle is designed around a 68mm system.
- Standard systems use external bearing BB cups that push the edges to 86.5mm.
- GXP, Shimano standard and FSA MegaExo, etc., basically have crankarms designed around a 24mm spindle diameter and an 86.5mm spindle length since they require the external BB bearing cups.
- BB386EVO is designed with a 30mm OD spindle and an 86.5mm wide bottom bracket shell.
- Therefore, BB386EVO uses the larger 30mm spindle (lighter, stiffer) of the BB30/PF30 and the 86.5mm bearing width (wider, stiffer), giving it all of the benefits of each system with none of the drawbacks.
The result is an overall lighter, stiffer, stronger system that also allows for frame builders to make a lighter, stiffer and stronger frame. It’s a true win-win.
Plus, if you were to buy a frame with the new BB386EVO standard, you could retrofit any non-BB30 crankset to it because they’re all based on the same 86.5mm effective BB width. They’ll offer sleeves to downsize from 30mm to 24mm for the retrofit.
The Parts, For Now.
The system uses press-fit bearings contained in their own sleeve as shown on the bottom left, similar in design to current PFBB30 systems with the same 46mm frame hole and all, it just sets the bearings wider. It gets better: The external BB cups on the right are English thread that’ll fit current standard 68mm BB shells and allow you to run the new BB386EVO cranksets! You read that right, you’ll be able to retrofit any non-BB30/PFBB30 frame to fit these new cranks, too. (byTheHive have something similar but it’s proprietary to their cranks)
FSA will launch the system with two cranksets, a K-Force and SL-K Light, that should be very similar to their corresponding MegaExo models in spec.
One measurement they mentioned heavily on the new cranks is U-Factor, which is the distance between the planes created by the crankarm bolt and the outer surface of the pedal threads. BB30 systems offered a 15mm distance, creating more of a curve in the crank. Standard systems have about 5mm, and the BB386 systems (FSA’s anyway) will have about 10mm, splitting the difference. This means a slightly curved crankset for better comfort and heel clearance but a stronger system than BB30 because the crankarms are straighter.
Real World Application – The 2012 BH Ultralight
BH’s new Ultralight takes full advantage of the new system to create a 747g road frame (size 56) with no rider weight limits and a lifetime warranty:
For comparison, a smaller size-54 G5 with extended seatmast is 810g out of the mold. The frame above had been ridden by Chris for two weeks prior to this presentation.
The BH Ultralight uses a new precision carbon molding techniques that is not only really light, but claims to set benchmarks in stiffness. The BB386EVO system allows for an all carbon bottom bracket shell, and BH USA president Chris Cocalis says it could eventually lead to breakthroughs in component construction like full carbon cranksets, including the spindle. The seat tube is a box section with extensive shaping to accommodate the front derailleur yet put the biggest contact section with the BB possible.
Frame is designed around the new FSA cranks, but is easily adaptable to Campy Ultra-Torque, Shimano 24mm, SRAM GXP and FSA’s MegaExo designs. The design allows for a full 80+ mm downtube width at the BB shell, larger diameter chainstays for a much stiffer frame where the power transfer occurs.
The Ultralight is 166% stiffer torsionally than the G5 and 125% side-to-side stiffness increase at the rear axle. Claimed weight is 747g for a 56, and there’s no rider weight limit and it comes with a lifetime warranty. Weight is with 17g worth of Parlee-developed matte clearcoat and decals, just like it’ll be sold. If you’re keeping track, yes, that’s an insanely light amount of paint.
It has a tapered headtube and nicely shaped junctions between it and the top- and downtubes. The derailleur hanger is forged from 7075 aluminum and is designed with FEA to determine the stiffest structure for precision shifting. The new fork is under 300g out of the mold and has an integrated crown race to eliminate a heavy steel part found on many carbon forks.
Downtube cable guides are fully slotted to accept barrel adjusters if you want them. The cable guide under the bottom bracket allows the cable housing to come from the shifters around the head tube to keep them from rubbing on the frame then, thanks to separate channels inside it, can criss-cross the cables inside the guide. This also keeps things cleaner looking, but you can run it crossed under the downtube, too, if you want.
Frame cost is going to be about $4,199 for the frame/fork/headset/seat collar. Available in July in XS through XL (53/54/56/57/59). Will also be offered as a complete bike. Spec isn’t finalized, but look for three to four builds for the U.S., more in Spain where they’re headquartered. No current version for Di2, but it’s on the books for development soon.
And here’s how you can build one up at 10.66lbs without any crazy parts…except perhaps the cassette. Build is Reynold’s RZR Wheels with Vittoria Crono Evo CS tubular tires; BH’s foreign-market-only Titan brakes (that looked remarkably similar to Feather brakes); FSA’s K-Force bar and post and OS99 stem; SRAM Red levers, chain and derailleurs; BB386EVO crankset/BB, Prologo c.one carbon saddle and a Driven cassette that I haven’t seen before:
At first I thought it was a custom machined-out SRAM Red cassette…it looks to be one piece but with a lot of material cut out from between the cogs. If anyone’s got any intel on this piece, leave a comment. Chris Cocalis said he can’t remember where he found it but has had it laying around for more than five years and just pulls it out when they’re building a showstopper lightweight bike…like this one.