Well Known and Active Website User
My TTR crankcases have been cracked and welded at some point in their racing life and I've just discovered that the crankcase hole for the bearing sleeve is out of round. I plan to have it line bored a minimal amount larger and make a new bearing sleeve to fit. Calculating the difference in thermal expansion between a 3" sleeve in alloy I get 0.0035" growth in the clearance over 110 degrees celsius. Can anyone tell me what the standard cold (say 20c) interference fit was? That much interference cold will lock up the CN bearings or should they be C3?