Went riding,(got call out by a friend), fun racing, more of a test and tune. All seemed fine until the last two passes...she felt off, but was still running. It’s an alcohol bike so when I got home I fired her up to warm up the engine, then I was planning on switching carbs to my gas ones on. Well in the warm up process all seemed ok, idling fine, and I went into the garage to get my gas carb and she died abruptly! Didn’t think anything except it was odd that it died so suddenly...,but it was dinner time and I waited tell after to check it out...went to fire her up and she felt tight like a piston was dragging...not good! I did know yet but I thought it was odd that a piston would seize at idle. But I didn’t what was wrong and didn’t have time to look at it. So yesterday I started looking, pulled the reeds...pistons skirts looked great, so I pulled the head...
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I was like wow, they look almost new! Then I was thinking shoot, must be rod or crank bearings, so I pulled the cylinder(mono block) and the rod bearings were free...
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So the ment it had to be crank bearings, but running out of time. Semi relieved, and hoping it was an outer crank bearing I tore the bottom end apart today....
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Billet crank broke! Bad day!