my 05 crf 250r, is starting to have the valve problems that i always here about. it is only my clutch side intake valve. i have had to shim it twice in the last three weeks and running out of shims small enough. i have always thought that the valve smashes into the head damaging the head, not the valve. what is it that actually goes bad or is damaged. isnt the aluminum, head softer than the hardened valve. i got a price on a new head 270$. what my question is; what gets actually damaged the valve or the head? and what are my options to fix this, besides going back to good old pre mix. i race 125 B motocross and ride it pretty hard if it means anything.
thanks for the help