How do I know what length bottom bracket I need?
To find out the size of bottom bracket needed, measure the inside of the bottom bracket shell in your frame, it will be 73mm, 70mm or 68mm. Some older frames may have Italian threaded bottom brackets, instead of the more modern English.
Should there be a gap between crank and bottom bracket?
No you don’t need a spacer – the axle does all the load bearing by itself.
How do you measure crank arm length?
Crank length is measured from the centre of the bottom bracket axle to the centre of the pedal axle. If you’re not sure what length the cranks on your bike are, the quickest way of finding out is typically to just look at the backside of your cranks, just below the pedal axle.
What are the dimensions of a Shimano bottom bracket?
Shimano cartridge bottom brackets are typically coded with a model designation and two numbers: shell width and length. Model designations include: Square Taper: CT21, LP27, UN40, UN51, UN52, UN71, UN72, UN91. Shell width in millimeters: 68 for standard ISO/British Length: overall spindle length in millimeters.
How big is a Shimano MegaExo crank spindle?
Designed to work in frames shell width from 68mm to 86.5mm. Designed to work in frames shell width from 68mm to 92mm. Splined interface much like Shimano HollowTech II. NOTE: FSA MegaEXO crank spindle diameters can be as large as 24.07mm.
What are the numbers on a Shimano cartridge?
Shimano cartridge bottom brackets are typically coded with a model designation and two numbers: shell width and length. Square Taper: CT21, LP27, UN40, UN51, UN52, UN71, UN72, UN91. These are all interchangeable if the other numbers match.
What kind of crankset does Shimano Hollowtech 2 use?
Hollowtech II ® Two-Piece Cranksets: Shimano’s latest top-of-the line system is a two-piece crankset. One piece is the combined right crank and spindle, the other piece is the left crank. Hollowtech II uses separate bearing modules that screw onto the opposite sides of the frame.