Discussion Starter · #1 ·
98 foreman 450es. I bought this bike a year ago in pretty bad shape, since then I have replaced piston , rings, cylinder, valve head, valves and seals. After I installed the new head and valve assembly and made sure the valves were set correctly on the comp. stroke, I was getting very little compression, like 30 psi. Long story short, in order to reach starting compression i had to back out the valve adjustment screw all the way and loosen the 3 bolds holding the lifter assembly down, one i did that, 90 psi and she fire right up. what the **** is up with this? what would cause the lifters to press the valves down when the assembly is fully seated?