For the past few years we have witnessed larger forces in the bike industry push what they call advancements onto the market but sometimes it is the smaller companies, the ones with engineers at the heart of them that create a product that offers something more substantial.
But before we go forward let’s look back a few years. Back when Boost 148 was launched, we chose to remain on the sideline because we were not convinced it was right. At Knolly our design philosophy demands that any performance feature change needs to be supported by a valid engineering position and proven rider performance benefits. And we were right to wait. When Boost was created it was designed to help fix a problem with 29er wheelsets and it was marketed as "a huge improvement in stiffness". When in actual fact it was simply the widest possible hub width that could be implemented while maintaining normal Q-factors of existing 2 x 10 speed drivetrains and it was limited by certain suspension designs rear stays. Boost 148 was then adopted as a solution by the "plus size" tire community because it gave another 3mm of tire clearance per side. Unfortunately, it did not solve all the tire size issues, and it resulted in unfavorable geometry when switching between 27.5” and 29” tires.
After creating a list of “must have” features to ensure our new line up of bikes can do everything we want, we decided that the only option is to move our entire lineup to the existing 12 x 157 rear spacing. We are calling it 157TRAIL because our Four by 4 suspension allows us to use the wide flange 157 hubs with 73mm BB shells on all our new trail models. The first models to launch will be the upcoming Fugitive 120mm travel 29er and Fugitive 135mm travel 29er. We made this choice because our design priorities are rooted in rider functionality, not in industry trends or marketing.
“We have significant experience running trailbike drivetrains on wide chain-lines. We don’t claim to be the first to bring this back to the market, but our “Trail” version of the 157 spacing allows us to achieve incredible design innovations in our new 2018 frames. We only incorporate design changes when there are legitimate benefits to the ride experience. If the current wave of 1x drive-train technology existed, the wider spacing revolution would have skipped right over 148mm and landed on 157mm. By using 157TRAIL, our new bikes give consumers the widest range of features possible with zero downsides.”
Noel Buckley, Knolly CEO
So why 157?
AVAILABILITY: 150 / 157 hubs have been around for years. The only difference between the two measurements is an end cap on the hubs and slots in the dropout for the 157 width. These hubs started out having flange widths that were similar to a standard 135 or 142 hub, and while some manufacturers have stayed with that flange width many have widened their flanges in an effort to make a more durable wheel. If we look at the dedicated Super Boost plus hubs they typically have a non-drive-side hub flange distance of 41mm and a drive side distance of 28. We noticed that many manufacturers have progressed with their hub design and even though they don't call them Super Boost plus they have the same flange width. So this means there are already numerous hubs and wheels available from some great companies. Heck, you might even have a set in your garage already!
TIRE SIZE: 157TRAIL allows us to eliminate tire width and focus on tire diameter. Riders can pick their wheel and tire combination based on intended purpose: be it a razor-sharp handling rocket ship, or a rock crawling monster truck (or anywhere between). The Fugitive is built around 29” wheels but it can also run 27.5” x 3.0” wheels/tires without compromise to the BB height.
The Fugitive with 29” wheels and 2.25 tire
The Fugitive with 27.5” x 3.0” wheels / tires
Q-FACTOR: 157mm hub spacing can be implemented using a flipped chain ring to maintain existing Q factors on XC / lightweight cranksets such as XTR, XO1 and Race Face Next SL.
Our new Fugitive can easily run one of the narrowest Q factor cranks on the market – the Raceface Next SL.
STIFFNESS: 157mm has a massive increase in stiffness over 142mm and even Boost 148. In fact, the increase in stiffness between 142mm and 157mm is almost three times of that between 142mm to 148mm Boost.
TIRE CLEARANCE: 157TRAIL provides the most options for tire size across all models. All Knolly 157TRAIL frames will easily clear tire widths up to 3.25".
Fugitive model shown with 29x2.6” tire illustrates the massive tire clearance on our new frames.
FRAME CLEARANCE: We have re-designed the entire rear-end area to keep things as tight as possible. The 157TRAIL spacing increases rear axle width by 15mm (7.5mm per side), and yet heel clearance of our new designs has only moved outward by 1.5mm per side! Our new 157TRAIL rear-end remains the same or in some cases narrower than existing Boost 148 bikes currently on the market.
Current model rear spacing (BLUE) compared to the Fugitive shows how the rear stays are only slightly wider and that we can continue to run a 73mm wide threaded BB shell. The new downtube cross section is also significantly larger for greater stiffness and BB support.
CHAINSTAY LENGTH: Due to our Four By 4 Linkage and Knolly’s forward mounted seat tube we do not need to extend chainstay lengths to accommodate larger wheel sizes, including standard sized 29" tires and high volume 27.5 Plus tires. Four By 4 also allows us to use 73mm bottom brackets shells and is front derailleur compatible.
The Fugitive 29er sports 430.5mm / 16.95” chainstays. BB height in slack is 325.5mm / 12.8”. Our forward mounted seat tube conveniently leaves enough space to store a spare tube and CO2 cartridge.
CHAINRING SIZE: Chainring clearance remains huge: at 36T for 29" models and 38T for 27.5" models
COMPATABILITY CHECK LIST:
Knolly has a reputation for producing bikes that last and we are known for not jumping on the latest trends. We have thousands of loyal riders that, year after year, have ridden our brand because of the performance of our suspension, the longevity of the product and the customer service we provide.
So when it came time to overhaul our entire model lineup we knew we have to live up to the expectations of our riders. Our move to 157TRAIL enabled us to design, build and deliver the highest performing mountain bikes in the industry. Again.