you are just sitting them in there? you arent mounting them securely?
if thats the case, I think vibration would be a contributing factor if not the entirely causitive one.
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El Pendejo Loco
2002 Suzuki Hayabusa
1507 "dry" block
Brocks megaphone
Spencercycle 10" swingarm
MPS auto shifter
Hays convertible clutch
Yea, that about sums it up...