hi

Has anyone any idea why my buell lightning keeps blowing the main shaft oil seal?

Cheers

You might need to give more info than that, circumstances, when it started, how/when it happens after you replace, ect.

Edit-BTW i wont have a clue even with enough info :D

not harley/buell specific but usually an engine that is building excessive crankcase pressure can blow out seals. find crankcase breather wherever it is on a buell and make sure its not clogged

What Lager said. That's the common cause of this problem.