It could be argued that fat bikes are set to become another mainstream segment of the sport instead of just a tiny niche. Salsa is one of several companies to now offer a carbon fibre chassis, and after taking our first look back in June, we’ve just taken delivery of its new Beargrease Carbon model.
Switching to carbon fibre from the more common aluminium offers the usual claimed benefits, including a stiffer and more responsive feel, better vibration damping (although in this case the tyres leave little left over for the frame to deal with), and certainly lighter weight. According to Salsa, a medium Beargrease Carbon frame weighs just 1,250g – more than a kilogram lighter than the aluminium version it replaces and not much heavier than standard carbon hardtails. The matching Salsa Makwa full-carbon fork adds another 720g.
Salsa says the new Beargrease also features a more race-friendly geometry with quicker handling characteristics than what we’ve normally come to expect from fat bikes, and our initial test rides have confirmed that claim so far. Despite the 4in-wide clown shoes, steering feels impressively normal.
Key characteristics include a 68.5-degree head tube angle, a suspension-ready fork with a more generous 51mm offset, and unusually short 440mm chainstays (the category-busting Surly Pugsley measures 448mm; the new Specialized Fatboy 455mm; the 9:ZERO:7 Whiteout Carbon 467mm).
A few splashes of color helps underscore the incredible down tube width on the salsa beargrease carbon:James Huang/Future Publishing
Through-axles are used throughout, with the 177x12mm rear and 142x15mm front spacing mimicking those of common 170mm and 135mm quick-release fat bike hubs. Here the move should be especially beneficial in terms of stiffness and handling precision given the huge gaps between the dropouts.
Our salsa beargrease carbon tester came with proven avid bb7 cable actuated disc brakes, which are often favored in snow bike circles for their greater reliability in extremely cold temperatures:James Huang/Future Publishing
Other features include a 1 1/8 to 1 1/2in tapered head tube with zero-stack cups, a 121mm-wide bottom bracket shell with press-fit cups (standard 100mm fat bike cranks will fit), a removable direct-mount front derailleur clamp, internal cable routing designed around full-length housing to protect against winter weather, and a slim 27.2mm seatpost to add a little more cushioning to the ride.
The 122mm-wide press-fit bottom bracket shell accepts the same cranksets as other fat bikes with threaded 100mm shells. that extra width allows for wider chain stay spacing, though, which boosts tire clearance. also note the size of the down tube in comparison:James Huang/Future Publishing
Naturally, tire clearances are very generous. Salsa says the rear end of the Beargrease Carbon is designed around 26x4in tyres on 82mm wide rims with a ‘full drivetrain’ but will also work with 4in tyres mounted on 100mm-wide rims. 29x3in tyres will supposedly clear, too, but only with a 1x setup. There isn’t enough room for new-school, ultra-fat 5in tyres through the stays but the fork will apparently clear 26×4.8in rubber on a 100mm-wide rim.
Salsa says the beargrease carbon frame is designed around 4.0James Huang/Future Publishing
Despite the enormous rolling stock and modest SRAM X7/X9/BB7 build of our tester, actual weight is still quite reasonable at 13.04kg (28.75lb) without pedals. The complete bike as shown retails for US$3,499/£2,799 and for more dedicated fat bike riders, there’s a high-end build with SRAM XX1 for US$5,499/£4,199. Framesets are also available for US$2,599/£1,599 and they come rather well equipped, including the usual frame and fork but also a Salsa Lip-Lock seatpost collar, a clamp-on direct mount front derailleur adapter, and Salsa Fat Conversion front and rear hubs set up for thru-axles with DT Swiss RWS skewers.
Salsa offers the beargrease carbon in one of two build kits. we received the lower priced version, which comes equipped with a mix of sram x7 and x9 drivetrain components:James Huang/Future Publishing