
Originally Posted by
MXNUT
I would be very surprised if the valves were not bent. Due to the combustion chamber design there are not many modern engines that have clearance when a valve is fully open and the piston comes up to TDC. .....

Originally Posted by
NordieBoy
......The Nordie was at 7,000rpm after changing down a cog when the belt snapped. The valves were sweet

Surprised the hell out of me. .....
This is a bit intriguing about lack of bent valves with belt driven motors. I'd have expected bent valves as well.
Wild and woolly theory's time - belt disengages from cam sprocket very quickly so removes inertia from system and valve springs strong enough to stop cam turning almost instantly and close valves. Apart from belts snapping more regularly this sample of two (that I know of) is good reason to run belts over chains. Then again chains don't snap, they stretch, get noisy and you replace them.
Like I said woolly engineering going on here!
Cheers R
"The ultimate result of shielding men from the effects of folly is to fill the world with fools." - Herbert Spencer, English Philosopher (1820-1903)
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