Pics of Her and old bad piston, thoughts!?

[aguita]

hey guys, well as told on my previous thread she finally went, after being a race bike back in 2004 and treated bad she finally went, the result..

all 4 valves
Piston
Bent Rod

I had a 450cc and a fallicon crank on the spare parts I got form the previous owner and Today I finally had it back together, tommorow im starting her up again..

any idea what caused the hole in the piston!?

[m_mcgranahan]

hmmm yeah not so pretty inside!

[rayspeed]

Hole in the piston by itself would be detonation from either old or bad gas... not high enough octane for its compression. However you mention bent rod and four valves and that would be more like a dropped valved that knocked that hole in there which could have been a problem with the top end. Otherwise if the valves were in intact but just bent that could be that it was overwound. Some might think that cant happen with a rev limiter but drop it into too low of a gear while you are hauling butt with good traction and it certainly can.