Surly Bikes (United States) - Years ago the Karate Monkey helped start the 29” wheel movement and, as time’s gone by, many companies ­– Surly included – have experimented with even more wheel sizes.

With so many different types and sizes of tires now on the market, riders have begun to understand the effect that tire width has on overall wheel diameter, and with ample tire clearance, you can see the benefits of multiple wheel sizes all on one bike. 27+ tires have the same rolling diameter as a 29” wheel, yet you get all the traction and floatation benefits of extra-wide knobbies. And that’s just the tires.

For 2019, the Karate Monkey SUS version features a 140mm travel Rock Shox Sektor RL suspension fork and a dropper post out the box. The Karate Monkey uses a horizontal dropout with a derailleur hanger that features Gnot-Boost spacing, which gives the rider the ability to run any kind of mountain bike hub they choose. 10 x 135mm QR, 12 x 142, or 12 x 148 Boost™ will all work in the Karate Monkey frame. The frame uses a 44mm headtube for broad fork compatibility and is ED coated for an added layer of internal protection. If, at any point, you decide you want to throw on some skinny meats, standard 29” wheels and tires can be swapped in with no issue. If you want to round-house kick some trail right in the face, the Karate Monkey is your sled.

Complete bike spec:

• Frame: Surly 4130 Cro-Moly Steel. Custom double butted externally flaired tubing. Horizontal slotted with derailleur hanger, Surly “Gnot Boost” 142 or 148mm hub spacing compatibility
• Fork: RockShox Sektor RL, 27.5 140mm travel, 51mm offset, 15x110 front axle, Disc.
• Seatpost Clamp: Surly stainless, 33.1mm
• Crankset: SRAM Descendant 32T
• Bottom Bracket: SRAM Powerspline
• Front Derailleur: None
• Rear Derailleur: SRAM NX Eagle
• Cog or cogset: SRAM Eagle 11-50t
• Chain: SRAM NX Eagle
• Headset: Cane Creek
• Brakes: SRAM Level hydraulic
• Brake Levers: SRAM Level hydraulic
• Grips: Velo single lock-on
• Rotors: SRAM Centerline 180/160
• Shifters: SRAM NX Eagle
• Stem: Promax, 31.8mm
• Handlebar: Salsa Rustler 31.8
• Saddle: WTB Volt Sport
• Seatpost: TranzX SP15, dropper post 80mm travel on XS/SM 120mm travel on MD/LG/XL
• Front Hub: 110mm, 15mm thru-axle, 32h
• Rear Hub: 148mm, 12mm thru-axle, 32h
• Rims: WTB Scrapper i40
• Tires: Surly Dirt Wizard 27 x 3, 60 tpi