skygazer6033
Elio Addict
I've questioned that myself (along with a dozen other valve train issues). With this OHC design the cam operates directly on the tappets without rockers so the mass is very low. Also we know it's a small bore long stroke engine so it's set up for low end torque and low rpm. Consequently the valve springs don't need to be real strong and there's only 6 of them. Roller lifters would add unnecessary complication as well as make the whole engine 1/2 to 1 inch taller for very little return.