We used to produce these, but due to tome constraints and unrealistic shipping costs from our country home in Canada, we no longer produce any parts. Any basic machine shop with a lathe can make any of the parts shown here, so feel free to print out the drawings have have these made. If you have a lathe and want to make these available for other AZ Forum Members for a fair price, feel free to contact us for a possible listing in our parts for sale thread.
There are now several different crank bearing systems and standards. The different standards do not allow interchangeability between bearings or cranksets. Having some knowledge of the standard will help the mechanic be aware of service options.
What is a bottom bracket? Your bottom bracket connects your cranks to your bike in such a way that they can rotate freely as you pedal and put power into the drivetrain. Shell and spindle widths vary depending on the type of bottom bracket.
A bicycle bottom bracket often called the "BB" by bicycle mechanics is that bearing and axle assembly that the crank arms are attached to. The bottom bracket shell is the part of the bicycle frame that houses the bottom bracket. Usually the chainstays, downtube and seat tube are attached the the BB shell.
FREE U. For those who are looking to upgrade the cranks on your mountain bike, or just need a replacement bottom bracketit's very important to make sure you get the correct bottom bracket for the job. The two major dimensions that differentiate bottom brackets of similar types are the shell width and spindle diameter.
The bottom bracket shell width is the width, in millimeters, of the frame where the bottom bracket is mounted. Bottom brackets must fit the frames interface type. For example, an english threaded bottom bracket can only be installed on a frame that accepts english threading.
Once upon a time, all bikes were made of steel. And the bottom bracket axle was a solid steel rod. There were cups in the bearings into which loose ball bearings fitted, with the axles having a curved surface which pushed against the ball bearings.