31-08-2019, 01:56 AM
(This post was last modified: 31-08-2019, 02:02 AM by Bob Culver.)
hi Tony B
The current tolerance for inner rings of bearings is 0 to 10 microns under, .0004 inch.
Cranks just to size may explain why so many bearings loosen.
Half of .0025 interference fit is defined as a force fit so .0025 would need brute force to assemble and the separate bearing parts would be unlikley to then fit together.
But it would cure the Seven rumble.
(Quarter of a thou is .00025, the factory tolerance, and probably the figure you recall?)
The current tolerance for inner rings of bearings is 0 to 10 microns under, .0004 inch.
Cranks just to size may explain why so many bearings loosen.
Half of .0025 interference fit is defined as a force fit so .0025 would need brute force to assemble and the separate bearing parts would be unlikley to then fit together.
But it would cure the Seven rumble.
(Quarter of a thou is .00025, the factory tolerance, and probably the figure you recall?)