Broken Mag Engine

[Steve Jones]

When Ang showed me the close up photo yesterday, I initially feared it was the new engine you've just finished putting together. At least that's not the case!! When I had something similar happen back in around 1997, the crank had broken across the rear crankshaft web. The front three quarters then flailed around inside the the crankcase thumping the side and punching a hole through it. That happened in the very few seconds it takes to hear the bang, de-clutch and stop. That was a 1 5/16 crank. Assume this is a 1 1/8?

As to repair, your laser welding man, whilst expensive, is, probably, your best bet.

Steve

Edited: The sploge of weld is a casting mark.