2023 Knolly Endorphin
Wheel Size: 27.5’’ or 29’’ front / 27.5’’ rear
Travel, MX configuration: 135 mm rear / 140 mm front
Travel, full 27.5” configuration: 150 mm rear / 160 mm front
- Sizes offered: XS, S, M, L
- Headtube angle: 64.5° / 65°
- Seat tube angle: 76° / 76.5°
- Reach: 469 (size Medium)
- Chainstay length: 432 mm (size Medium)
- Sizes offered: XS, S, M, L
- Headtube angle: 64° / 64.5°
- Seat tube angle: 75.5° / 76°
- Reach: 465 (size Medium)
- Chainstay length: 432 mm (size Medium)
Frame Material: Aluminum
Price:
- Frame w/ Fox Float X Factory: $2,499
- Complete Bikes: $4,199 to $5,499
Intro
The original Knolly Endorphin cropped up during the heyday of 27.5’’ wheeled Trail bikes, and while there are still some around, including the Pivot Shadowcat, Yeti SB135 (full review coming very soon), and a handful of others, their numbers have dwindled in recent years.
Knolly clearly still thinks little wheels have their place, though (we totally agree), and they’ve done something pretty interesting with the new Endorphin. It’s designed to be run with either matching or mixed wheel sizes, but in contrast to most bikes that can make that swap, the Endorphin gets a 27.5’’ rear wheel either way and can be configured with your choice of a 27.5’’ or 29’’ front wheel — with substantial changes in suspension travel to go along with it.
Part of the reasoning behind the smaller wheel size is that Knolly prioritizes fit for shorter riders on the new Endorphin, with frame sizes starting with a very small XS and topping out at a Large (Knolly says that the run of Large frames will be limited). Smaller wheels offer more clearance and more manageable stack heights for shorter folks, and Knolly is talking about the Endorphin as being a relatively playful, nimble sort of Trail bike — but how they’ve gone about some of the details is pretty interesting.
The Frame
Knolly’s distinctive design language and suspension layout are still present on the new Endorphin, but a lot of the details have been refined — and Knolly says that many of those updates will be carrying over to the rest of the line, in what they’re calling their “sixth-generation” models.
The new Endorphin frame is offered in aluminum only and features a new tube set with straighter lines, a beefed-up one-piece rocker link, Enduro bearings in all the pivots (now with flat faces at the bearing locations to make pressing them in and out easier), a SRAM UDH, and a variety of other refinements. The cable routing is internal, with large bolt-on ports to help ease routing. The Endorphin uses a threaded bottom bracket shell, post mount brake tabs for a 180 mm rotor, and Knolly’s typical 157 mm Super Boost rear hub spacing. A flip chip at the lower shock mount toggles between two geometry settings (more on those in a minute).
Knolly’s familiar Fourby4 suspension layout — effectively a Horst-link setup with an additional pair of links to actuate the shock — sticks around on the Endorphin. Knolly doesn’t publish any kinematic data for the Endorphin but says that the layout gives them some extra flexibility to tune the leverage curve independently from braking and pedaling characteristics.
In terms of bikes that can run different wheel sizes, it’s more common for them to get a 29’’ front wheel with a provision to toggle between a 27.5’’ or 29’’ rear. This is in part because swapping between a 27.5’’ and 29’’ front wheel makes for bigger geometry changes once you take into account the change in fork length. The Endorphin goes the other way by making a substantial change in suspension travel along with the wheel size swap to even things out. For reference, Knolly specs a 140mm-travel fork on the Endorphin MX builds, paired with a 50mm-stroke shock (in a 185 mm Trunnion mount length) to produce a stated 135 mm of rear-wheel travel; the 27.5’’ builds get a 160mm-travel fork and a 55mm-stroke shock, which reportedly bumps the rear travel up to 150 mm.
Knolly also notes that their straight, uninterrupted seat tube offers especially good dropper post insertion and that most folks should be able to run at least a 175 mm post on the Endorphin, even down to the XS frame. There’s room for a water bottle inside the front triangle on the whole size range, plus an accessory mount underneath the top tube.
Fit & Geometry
Knolly has made a real point of designing the Endorphin to fit “fun-sized people.” It’s offered in sizes Extra Small, Small, Medium, and a limited run of Large frames; Knolly says those cover folks down to 4’11’’ (150 cm). Reach starts at 415 mm and grows by 25 mm per size (up to a pretty-long 490 mm on the Large), paired with size-specific chainstay lengths (428 mm on the XS and Small, 432 mm on the Medium, and 436 mm on the Large). All four sizes get a 64.0° headtube angle and 75.5° seat tube angle in the low position, both of which steepen by 0.5° in the high one.
All of those numbers are for the Endorphin MX; the 27.5’’ configuration steepens the head and seat tube angles by half a degree and adds a few millimeters to the reach in the process. The bottom bracket height for both is stated at 343.5 mm (high) or 333.5 mm (low), but the 27.5’’ configuration is presumably a little lower than the MX one, since the headtube angle winds up a touch steeper.
The Builds
Knolly is offering three Endorphin builds for the time being, with two getting the MX wheel size option and a lone 27.5’’ build. All three are clearly meant to offer solid performance without breaking the bank — there aren’t any truly budget or full-bling options here. The Deore 27.5’’ and Deore MX builds are mostly the same, apart from the suspension package to handle the travel changes (and of course the front wheel size); the XT MX build gets a Shimano XT drivetrain and brakes, Fox Factory suspension, and a few other odds and ends, such as a higher-end bar and stem package and an upgraded headset. All three builds get a Maxxis Assegai MaxxGrip Exo+ front / DHR II MaxxTerra Exo+ rear tire combination.
Here are the highlights for all the Endorphin builds:
- Drivetrain: Shimano Deore 12-speed
- Brakes: Shimano Deore 4-piston
- Fork: Marzocchi Z1 (160 mm)
- Shock: Marzocchi Bomber Air
- Wheels: DT Swiss M1900
- Dropper Post: SDG Tellis
- Drivetrain: Shimano Deore 12-speed
- Brakes: Shimano Deore 4-piston
- Fork: Fox 34 Performance (140 mm)
- Shock: Fox Float X Performance
- Wheels: DT Swiss M1900
- Dropper Post: SDG Tellis
- Drivetrain: Shimano XT 12-speed
- Brakes: Shimano XT 4-piston
- Fork: Fox 34 Factory (140 mm)
- Shock: Fox Float X Factory
- Wheels: DT Swiss M1900
- Dropper Post: SDG Tellis
Some Questions / Things We’re Curious About
(1) How coherent does the design of the Endorphin feel in both wheel-size configurations, and how much does toggling between them change its character? It’s interesting that the longer-travel 27.5’’ configuration is also a little steeper than the shorter-travel MX one, so how does that all pan out on the trail?
(2) And how does the Endorphin ride in general? It’s been a long time since we’ve been on a Knolly and we’re quite curious to see how their whole design philosophy comes together — including the unconventional Fourby4 suspension layout.
Bottom Line (For Now)
The new Knolly Endorphin offers something pretty interesting — a longer-travel 27.5’’ Trail bike or a shorter-travel MX one on the same frame, in sizing that’s especially focused on working well for shorter (or at least, not-super-tall) folks. We’re curious to get on one to see how it stacks up and will follow up with a full review if we’re able to make it happen.