We've noticed excessive wear on the cam due to heavy duty valve springs. For 2 1/2 years we used nothing but xr70 springs with no trouble. Six months ago we started using these springs and in 40 hours of running time the intake lobe was worn down 1/8". (So far we replaced 4 cams and valve springs) If anyone had a head done by us please check for cam wear. If you have it please contact us for replacement on the cam and valve springs. We just finished our new xtreme 110 bike and went back to the old valve spring set up with no spring lock or flotting of the valves.(which means heavy duty valve springs are not the way to go).
Jim
www.precision-racing-components.com
(Paid advertiser of planet minis)
Jim
www.precision-racing-components.com
(Paid advertiser of planet minis)