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Big Dummy is a Long-Tail Cargo Bike built for hauling large loads and small passengers wherever they need to go.

Take Your Longtail Bike Anywhere

Since its introduction in 2008, many a family have ditched one or both of their cars thanks to Big Dummy. We’ve also seen many entrepreneurs and small business owners minimize their carbon footprint and incorporate Big Dummy into their business model.

Big Dummy is a dependable grocery getter, the modern day mini-van, the company car, and a human-powered car replacement. It’s all those things and more in that there’s no limit to what it can haul — as long as it falls within the 400-pound weight limit.

  • Dedicated single-piece frame increases stiffness and decreases torsional flex
  • Human cargo compatible with the use of Dummy Rail Collars
  • Vertical, 135mm spaced dropouts with fender eyelets; Rohloff compatible
  • Clearance for 26" x 2.5" tires with fenders
  • 400-lb. combined rider and cargo weight limit

Bike Capabilities

  • 5/5 with Car Replacement Car Replacement: 5 out of 5
  • 5/5 with Passengers Passengers: 5 out of 5
  • 3/5 with Off Road Off Road: 3 out of 5
  • 5/5 with Trailer Compatibility Trailer Compatibility: 5 out of 5

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

Close-up of Bruised Ego Purple Surly Big Dummy Deck
Surly Big Dummy with Front Rack and cardboard box attached
Surly Big Dummy fully loaded with front rack, trailer, and many cardboard boxes loaded everywhere
Surly Big Dummy close-up of corn dog seat tube decal
Close-up of Surly Big Dummy Rail Collars attaching Dummy Rails to Big Dummy Frame
Surly Big Dummy Bags on Big Dummy Bike

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Where to Buy

Surly Big Dummy Cargo Bike, Bruised Ego Purple, side view on white background

Specifications

Frameset

Frame
100% Surly Chromoly steel, Natch tubing, double-butted main triangle, TIG welded
Fork
100% Surly Chromoly steel, Natch tubing, double-butted tapered fork blades, TIG welded, E.D. coated
Color
Bruised Ego Purple

Components

Headset
Cane Creek 40 Series
Stem
Kalloy 31.8
Handlebar
Surly Terminal Bar
Grips/Bar Tape
Velo Black
Seatpost
Kalloy 27.2
Saddle
Selle Italia X-Base

Drivetrain

Front Derailleur
N/A
Rear Derailleur
microSHIFT Advent 1x9 Speed, RD-M6195M
Cassette
microSHIFT Advent 11-46t, 9-speed
Chain
KMC X10 10-Speed
Crankset
Race Face, 32t
Bottom Bracket
Race Face BSA 24
Shifter
microSHIFT Advent Trail 1x9 shifter, SL-M9195-R
Brake Levers
Avid FR-5
Brake Caliper
Avid BB7 S MTN
Rotors
SRAM CenterLine 200/180mm

Wheels

Front Hub
Novatec QR x 100, 36h
Rear Hub
Novatec QR x 135, 36h
Spokes
DT Swiss 2.0 Stainless
Rims
OE, 38mm, 36h
Tires
Surly ExtraTerrestrial Tire - 26 x 2.5", Tubeless, Folding, Black/Slate, 60tpi

Complete bike spec subject to change

MY23 Big Dummy Geometry
units:

Select a few bike sizes to compare.

SIZE SM MD LG
Rider Height 63–70 1600–1778 66–72 1676–1829 70–77 1778–1956
Reach 16.1 409.9 17.0 431.1 17.6 447.2
Stack 22.5 571.1 23.6 599.3 24.7 627.4
Head Tube Angle 70.0° 70.0° 70.0°
Head Tube Length 5.9 150 7.1 180 8.3 210
Seat Tube Length 16.0 406.0 17.0 432.0 20.0 508.0
BB Drop 1.6 40.0 1.6 40.0 1.6 40.0
Wheelbase 57.8 1469.0 59.1 1500.4 60.1 1526.8
Chainstay Length 32.3 821.0 32.3 821.0 32.3 821.0
Top Tube Length, Effective 23.2 590.0 24.4 620.0 25.4 645.0
Seat Tube Angle 72.5° 72.5° 72.5°
Standover Height 28.5 725.0 30.4 773.0 32.4 823.0
BB Height 11.8 299.0 11.8 299.0 11.8 299.0
Stem Length 2 3/4 70 2 3/4 70 3 1/7 80
Stem Angle
Handlebar Width 28 1/4 718.0 29 735.0 29 735.0
Crank Length 6 2/3 170.0 6 8/9 175.0 6 8/9 175.0
Fork Length 16.4 417.8 16.4 417.8 16.4 417.8
Fork Rake 1.7 43.0 1.7 43.0 1.7 43.0

All dimensions are preliminary and subject to change * Standover is measured from the top of the TT, at the center, with a tire measuring approximately Ø676mm

Frame Construction

100% Surly Chromoly steel, Natch tubing, double-butted main triangle, TIG welded

Fork Construction

100% Surly Chromoly steel, Natch tubing, double-butted tapered fork blades, TIG welded, E.D. coated

Rear Dropout Configuration

Vertical

Rear Hub Spacing

10 x 135mm

Rear Brake

51mm IS (160-203mm)

Front Brake

51mm IS (160-203mm)

Head Tube

Ø34mm

Steerer Tube

Ø28.6mm (1-1/8")

Crown Race

Ø30mm (1-1/8")

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

EC34

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

EC34

Seat Collar

Ø33.1mm

Seatpost

Ø30.9mm

Max Post Insertion

Small: 375mm

Medium: 255mm

Large: 331mm

Dropper Compatible (Routing)

Yes, internal

Front Derailleur (Clamp)

High direct-mount top-pull (Ø34.9mm)

Max Chainring (CL)[3]

No frame limitations

Bottom Bracket

73mm BSA threaded (1.37" x 24TPI)

Design Wheel/Tire Sizes

26 x 2.3"

Tire Clearance Frame [1]/[2]

26 x 2.5" (w/ or w/o fenders)

Tire Clearance Fork [1]

26 x 3.0" (w/o fenders)

26 x 2.8" (w/ fenders)

Alternate Wheel-Tire Sizes

27.5 x 1.5-2.0" w/ or w/o fenders

700c x 28-32mm w/ or w/o fenders

Rigid Fork Spec

420 x 43mm

Max Suspension Fork Length

N/A

Fork Offset

43mm

Front Hub Spacing

10 x 100mm

Bottle Mounts Frame

Small: Two Standard, One 3-pack

Medium and Large: Three Standard; One 3-Pack

Bottle Mounts Fork

Four 3-Pack

Rack Mounts Frame

Yes (Surly Dummy Rails)

Rack Mounts Fork

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

Fender Mounts Frame

Yes

Fender Mounts Fork

Yes

  • [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 frame.
    [3] Listed chainring clearance is worst case scenario.  Clearances vary widely depending on components and configurations.

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.