[Fot] Beaten By Equipment

[marty sukey]

My Jefferson 500 weekend has been cut short by a broken crankshaft key. Post break inspection in the paddock shows some weird stuff going on.  The key itself only engaged into the crank sprocket for a length of about 3/16 to 1/4 inch.  It is at this point where it sheared off. The crank is a NOS Moldex that was made probably 25 years ago. I installed it a couple of years ago, it probably has 3 race events on it. When I look at the location of the keyway in the Moldex crank and compare it to a stock Spitfire 1296 crank it looks like the keyway has been machined about 1/4 inch forward on the Moldex. I did not pay any attention to this upon assembly, never gave it a thought. This did not allow for enough engagement into the crank sprocket me thinks. My thoughts are to have a new keyway machined into the crank farther back.  Has anybody else seen anything like this?  The Jefferson 500 was not kind to Spitfires. 3 for 3 went down for the count due to issues.

Marty
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