Bikes. Parts. Chaos.

Karate Monkey is a highly-versatile trail bike that plays the part of 29er and 27.5+ equally well.

Karate Monkey delivers a resilient, lively ride on all sorts of gnarly terrain. Its frame is a highly-versatile canvas for whatever dirty masterpiece your brain cooks up. According to our computing machine (Thor) it can be set up in approximately 487 different configurations.

Originally designed as a 29er (and the frame that helped spark the 29” wheel movement), the latest Karate Monkey is designed to perform just as admirably as a 27.5+ rig as well. This allows you to pick your poison — provided your poison is having a really great time while permanently donning a shit-eating grin, of course.

  • Modern trail standards: dropper post compatibility, 44mm headtube, Gnot-Boost rear spacing, thru-axles, suspension corrected fork
  • Compatibility with most mountain bike standards makes it the perfect parts bin bike (no rim brakes allowed though)
  • Clearance for 29” x 2.5” or 27.5” x 3” tires

Bike Capabilities

  • 5/5 with Singletrack
  • 4/5 with Bikepacking
  • 3/5 with Commuting
  • 4/5 with Tire Clearance

NOTE: You can ride your bike wherever the hell you want, but this is what we think this bike is best at.

Karate Monkey in woods
Karate Monkey over rocks
Karate Monkey on rough trail
Karate Monkey on dirt
Karate Monkey downhile
Karate Monkey at sunset
Karate Monkey in wildflower field
Karate Monkey on boardwalk
Karate Monkey on rugged trail

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Where to Buy

Karate Monkey Front Suspension Bike - Lemon Lime Soda

Specifications

Frameset

Frame Surly 4130 Chromoly Steel

Custom double butted externally flaired tubing. Horizontal slotted with derailleur hanger, Surly “Gnot Boost” 142 or 148mm hub spacing compatibility

Fork Surly 4130 Chromoly Steel

483mm axle-to-crown x 47mm offset, 110mm hub spacing, tapered and butted straight blade, 4130 Chromoly. 51mm I.S. disc mount

Seatpost Clamp Surly stainless, 33.1mm

Components

Headset Cane Creek
Brakes SRAM Level
Brake Levers SRAM Level
Rotors SRAM Centerline 180/160
Grips Velo single lock-on
Shifters SRAM NX
Stem Promax, 31.8mm
Handlebar Salsa Rustler 31.8mm
Saddle WTB Volt Sport
Seatpost Promax 30.9mm

Drivetrain

Crankset SRAM NX 30t
Bottom Bracket SRAM Power Spline
Front Derailleur None
Rear Derailleur SRAM NX
Cog or cogset Sunrace 11 speed 11-42t
Chain KMC X11EL-1

Wheels

Front Hub Novatec, 32h, Thru-Axle
Rear Hub Novatec, 32h, Thru-Axle
Rims WTB Scrapper i40 TCS
Tires Surly Dirt Wizard 27 x 3, 60 tpi

Frameset

Frame Surly 4130 Chromoly 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

Components

Headset Cane Creek
Brakes SRAM Level hydraulic
Brake levers SRAM Level hydraulic
Rotors SRAM Centerline 180/160
Handlebar Salsa Rustler 31.8
Grips Velo single lock-on
Shifters SRAM NX Eagle
Stem Promax, 31.8mm
Saddle WTB Volt Sport
Seatpost TranzX SP15, dropper post 80mm travel on XS/SM 120mm travel on MD/LG/XL

Drivetrain

Crankset SRAM Descendant 32T
Bottom Bracket SRAM Power Spline
Front Derailleur None
Rear derailleur SRAM NX Eagle
Cog or cogset SRAM Eagle 11-50t
Chain SRAM NX Eagle

Wheels

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
Karate Monkey 27.5+ Geometry
units:
  • in
  • mm
XS SM MD LG XL
Reach 14.8 377 15.8 402 16.8 427 17.7 450 18.6 472
Stack 23.5 597 23.5 597 23.5 597 23.9 606 24.2 615
Head Tube Angle 69.0° 69.0° 69.0° 69.0° 69.0°
Head Tube Length 3.9 100 3.9 100 3.9 100 4.3 110 4.7 120
Seat Tube Length 13.0 330 14.5 368 16.5 419 18.5 470 20.5 521
BB Drop 2.2 55 2.2 55 2.2 55 2.2 55 2.2 55
Wheelbase 41.5 1053 42.4 1078 43.4 1103 44.4 1129 45.5 1155
Chainstay Length 16.7 423 16.7 423 16.7 423 16.7 423 16.7 423
Top Tube Length, Actual 21.6 549.7 22.1 560.4 22.6 575 23.5 597.5 24.6 624.5
Top Tube Length, Effective 22.0 560 23.0 585 24.0 610 25.0 635 26.0 660
Seat Tube Angle 73.0° 73.0° 73.0° 73.0° 73.0°
Standover Height 29.3 743 29.9 759 30.8 783 32.0 812 32.6 827
Fork Length 19.0 483 19.0 483 19.0 483 19.0 483 19.0 483
Fork Rake 1.9 47 1.9 47 1.9 47 1.9 47 1.9 47

*Standover is measured from the top of the TT, at the center, with a tire measuring approximately Ø749mm

XS SM MD LG XL
Reach 14.2 361 15.2 387 16.2 412 17.1 434 18.0 457
Stack 23.9 607 23.9 607 23.9 608 24.3 617 24.7 627
Head Tube Angle 67.5° 67.5° 67.5° 67.5° 67.5°
Head Tube Length 3.9 100 3.9 100 3.9 100 4.3 110 4.7 120
Seat Tube Length 13.0 330 14.5 368 16.5 419 18.5 470 20.5 521
BB Drop 1.7 44 1.7 44 1.7 44 1.7 44 1.7 44
Wheelbase 42.2 1071 43.1 1096 44.1 1121 45.2 1147 46.1 1172
Chainstay Length 16.7 423 16.7 423 16.7 423 16.7 423 16.7 423
Top Tube Length, Actual 21.6 549.7 22.1 560.4 22.6 575 23.5 597.5 24.6 624.5
Top Tube Length, Effective 22.2 565 23.2 590 24.2 615 25.2 640 26.2 665
Seat Tube Angle 71.5° 71.5° 71.5° 71.5° 71.5°
Standover Height 29.8 757 30.5 775 31.4 797 32.5 826 33.7 855
Stem Length 60 70 70 70 80
Stem Angle
Handlebar Width 750 750 800 800 800
Crank Length 165 170 175 175 175
Fork Length 20.5 521 20.5 521 20.5 521 20.5 521 20.5 521
Fork Rake 2.0 51 2.0 51 2.0 51 2.0 51 2.0 51
Frame Construction

4130 Chromoly, Natch tubing, double-butted main triangle, trumpet flaired tubes, TIG welded, ED coated

Fork Construction

4130 Chromoly, Natch tubing, double-butted tapered fork blades, TIG welded, ED coated

Rear Dropout Configuration

Horizontal slotted with optional vertical dumpout

Rear Hub Spacing

"Gnot-Boost" 145mm
12 x 142mm or 12 x 148mm (Surly axle included)
10 x 135mm with Surly 10/12 Adapter Washers (not included)

Front Hub Spacing

15 x 110mm (Surly axle included)

Rear Brake

Disc - 51mm I.S. (203mm max rotor)

Front Brake

Disc - 51mm I.S. (203mm max rotor)

Head Tube

Ø44mm

Steerer Tube

Ø28.6mm (1-1/8")

Crown Race

Ø30mm (1-1/8")

Stock Headset Upper (S.H.I.S)

ZS44/28.6

Stock Headset Lower (S.H.I.S)

EC44/30

Seat Collar

Ø33.1mm

Seat Post

Ø30.9mm

Front Derailleur (Clamp)

High direct mount top-pull (Ø34.9mm)
26mm offset adapter (not included) for 142 or 135mm rear hub spacing
29mm offset adapter (not included) for 148mm rear hub spacing

Max Chainring (CL) [3]

1x (Mtn):  28T
2x (Mtn):  24/34T
1x (Boost):  32T
2x (Boost):  24/36T

Bottom Bracket

73mm threaded (1.37" x 24TPI)

Tire Clearance Frame [1]/[2]

27.5 x 3.0”
29 x 2.5"

Tire Clearance Fork [1]

29 x 3.0”

Rigid Fork Spec

483 x 47mm

Max Suspension Fork Length [4]

551 x 51mm (27.5+ 140mm)

Bottle Mounts Frame

1 Standard + 1 Three-Pack (XS - M)
2 Standard + 1 Three-Pack (L - XL)

Bottle Mounts Fork

2 Three-Pack

Rack Mounts Frame

Yes (upper and lower threaded)

Rack Mounts Fork

Yes (upper, lower, and mid-blade threaded)

Fender Mounts Frame

Yes

Fender Mounts Fork

N/A

Other Features

Internal dropper post routing compatible

[1] Different tire and rim combinations will result in different clearances.  
[2] Depending on drivetrain configuration, tire clearance may be limited by the chain and not the frame.
[3] Listed chainring clearance is worst case scenario.  Clearances vary widely depending on components and configurations.
[4] Suspension fork length listed at full extension (not at sag)

FAQ & Reviews

Support

Frame Warranty

LIMITED WARRANTY

This Surly product is warranted against defects in materials and workmanship for three years from the date of retail purchase of the product, subject to the limitations detailed below. Save your dated receipt for proof of purchase.

This warranty does NOT cover the following:

  • Damage due to improper assembly or follow-up maintenance or lack of skill, competence or experience of the user or assembler
  • Products that have been modified, neglected, used in competition or for commercial purposes, misused or abused, involved in accidents or anything other than normal use
  • Installation of components, parts or accessories not originally intended for or compatible with bicycle as sold
  • Damage or deterioration to the paint, surface finish, aesthetics or appearance of the product
  • Normal wear and tear
  • Labor required to remove and/or refit and re-adjust the product within the bicycle assembly

This limited warranty is expressly limited to the repair or replacement of a defective product, at the option of Surly, and is the sole remedy of the warranty. This limited warranty applies only to the original purchaser of the Surly product and is not transferrable. This warranty applies only to products purchased through an authorized dealer or distributor. In no event shall Surly be liable for any loss, inconvenience or damage, whether direct, incidental, consequential, or otherwise resulting from breach of any express or implied warranty or condition, of merchantability, fitness for a particular purpose, or otherwise with respect to our products except as set forth herein.

This limited warranty gives the consumer specific legal rights, and those rights and other rights may vary from place to place. This limited warranty does not affect your statutory rights.

TO THE EXTENT NOT PROHIBITED BY LAW, THESE WARRANTIES ARE EXCLUSIVE AND THERE ARE NO OTHER EXPRESS OR IMPLIED WARRANTIES OR CONDITIONS INCLUDING WARRANTIES OR CONDITIONS OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.