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O.D. Crank

O.D. Crank
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O.D. Crank

We designed our O.D. crankset to offer frame and tire clearance while maintaining a reasonable q-factor (pedal stance). Maximizing the distance between the chain and the tire is important on fat bikes such as our Pugsley and Moonlander, or if you’re running really big tires and rims on some other bike (like our new Krampus, for example). With normal cranks, wide tires on wide rims can rub the chain when in the lowest, or farthest-inboard, gear combinations. Like our MWOD crank, the O.D. crank doesn’t just add a longer spindle to move the rings outboard. Rather, it does away with the big ring of a standard triple and moves the middle and granny rings to the outer and middle positions. This effectively moves the rings outboard without moving the arms outboard too. The O.D. is a simple, dedicated version of this idea. Neato!

Forged of 7000 series T6 aluminum, the O.D. crank is a 2-piece, with spindle embedded inextricably in the drive side arm. It’s a dedicated 2x, although its chainline is outboard a bit compared to standard mountain cranks, and it is 9 and 10 speed compatible. We offer versions to fit 73mm bottom bracket shells and two versions to fit 100mm BB shells: one for Pugsleys (to accommodate the offset required for 4˝ tires) and one for Moonlanders (frames offset for 5˝ tires). Each of these will be available as complete cranks (arms, spindle, rings, and bearings) in 170mm and 175mm lengths. 180mm will be available too, but as arm sets only. Completes for 73mm BB shells will have 39/26t rings. The 100mm BB shell versions will have 36/22t rings, and we are also offering an aftermarket version with a PF41 bottom bracket and 132mm spindle. The 132mm, PF41 bottom bracket O.D. crank is what goes on our Ice Cream Truck bikes, so if you've got that setup, that's your crank. We’ll also offer 33t and 20t rings separately. These chain rings are designed to shift best in specific combinations….change to a 39/22t, for example, and your shifting will suffer. The bearings on which they spin are also worth mentioning: we’ve upgraded our bearings on these and our Mr. Whirly and MWOD cranksets to aftermarket Enduro bearings with double labyrinth seals, meaning they actively shed and stay clean of dust, muck, and grime, even in wet and muddy climates. All O.D. cranks are available in black.

OD Crank Instructions
Crankset Chainlines and Basic Dimensions

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Choose:
  • 100mm Moonlander

  • 100mm Puglesy

  • 73mm

Choose:
  • 170mm

  • 175mm

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