Thus far, Pivot is the only one making trail mountain bikes with a 157mm rear axle standard, calling it Super Boost. Now, Canadian MTB brand Knolly is about to join them with their new 157TRAIL design. Having held off of regular 148mm Boost axle spacing, they say this wider format gives them more tire size options, better suspension design profiles, and zero crank or Q-factor compromises.
Quick background: 157mm hubs have been used for Downhill for ages, so it’s not a new standard. What’s relatively new is the combination of that hub standard with regular mountain bikes. And wheel brands like Industry Nine (among others, including custom wheelbuilders) can easily lace up the appropriate hub to whatever rim you want.
Knolly is using the extra width at the back to make their bikes ready for anything from 29×2.6 to 27.5×3.25. So you can choose the right wheel and tire combo for the day, without (they say) affecting BB height. They say the extra hub flange spacing width provides a massive 31% increase in lateral stiffness, too, so the wheels themselves get better.
Other than that, fit and finish stay the same. They’re even able to keep a short 16.95″ (430.5mm) chainstay length. And chainstay width only spreads by 1.5mm, so heel clearance is still good, letting it work with narrow Q-factor cranks like the Race Face Next SL in a regular threaded 73mm BB shell.
The nearly universal move to wide-range 1x drivetrains helps make this happen. While Knolly says their design is front derailleur compatible, appearances suggest it’s single-ring optimized. The numbers say it’ll fit up to a 36-tooth single ring on 29er builds, and 38-tooth rings with 27.5″ tires.
THE KNOLLY FUGITIVE 29er
The first bike to get their new 157TRAIL design is the upcoming Knolly Fugitive 29er, which will be their first 29er mountain bike, too. Coming this spring, it’ll be a 120mm travel trail bike designed with 120-140mm forks in mind. Head angle is around 66º (+/- depending on fork travel). More info as we get it.
