What caused this failure???

I will add a third theory to oil ratio used in a 2 stroke. The more oil used in your mix of fuel/oil/air leans the motors air/fuel ratio.
We were told a similar story by a Rotax dealer. His theory is that 8 ounces of oil in the gas instead of the reccomended 2.6 ounces of oil caused a lean mixture which caused overheating which seized the piston causing the bearing to fail. 🤷🏻‍♂️
 
Cylinder and piston. Did this seize?
 

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I can't really see and have never seen an engine with that damage caused when running extra oil. Never. And piston shows damage and signs of wear all around. I have seen this kind of damage with air leaks though.
 
I think it had other issues before the pin/cage failed. He sent me some extra pictures and I can see signs of the piston seized on different areas all around. The ring area also show signs of damage that could have happened before the cage failed, and he told me the engine lost performance at one point but kept running till he reached the pits. If the cage fails like that before anything else happened he wouldn't have kept the engine running. That engine might have been overheating way before the cage finally gave up. Or some air leak too.
 
I would agree. Wrist pin bearing failure. The rest is damaged caused by the engine eating the broken bearing.
Whatever happened 1st I still see there has to be a reason for that failure, especially after watching some of the extra pics he sent me.
 
We were told a similar story by a Rotax dealer. His theory is that 8 ounces of oil in the gas instead of the reccomended 2.6 ounces of oil caused a lean mixture which caused overheating which seized the piston causing the bearing to fail. 🤷🏻‍♂️
The more air into an engine the more hp.
 
Carb,timing,flex too short,no oil in fuel,air leak around intake or reeds(engine will have a dead spot in it)too hot of spark plug.running a piston too long and mechanical failure.i had a piston in a sudam and i burnt a hole in it the size of a quarter.
 
Victor is thrashing on the 450 with the Birky this week. Hopefully ready by Thursday so we can roll out to Roebling Road on Friday. Would like to see how it holds up on the Daytona big track later this year.
 
Looks like the piston is blue. Got hot. The parts look dry, not oily. It’s always impressive to look at a failure. Expensive and heart breaking though.
 
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