Did an engine rebuild on a KTM Duke 125 today, 10,000 miles. (Been waiting a month for bits!).
Really small noise from the engine, I said we can strip it but can't guarantee to find anything.
Even down to just rotating the crank in the cases by hand there was just a miniscule rough spot at TDC, no play in crank at all.
Cannot believe how quiet it was and how there wasn't any more damage, just LHS main bearing cage absolute shot.
Had one in before that sounded worse, told customer we needed to strip engine but he carried on regardless, 30 miles later it was bin fodder.
So seems a common theme on these engines..
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