[69birdboy]

I've got a street 400 that has now broken two valve springs. The first one was on the exhaust and I replaced it with a stock spring. That was a few thousand miles ago. Now, an intake spring is broken (at least this one didn't take the lifter and pushrod with it!).

I'm told that my cam has too much lift for a stock-type valve-train and the heads must come off for some work. Lift is .463/.485. I'd like to verify that before I go to the trouble to pull the heads, but I'm not sure how to verify it. My google and forum searches have been fruitless.

Suggestions? Ideas?

[PunchT37]

You most prolly are having a retainer to guide clearance issue and/or coil bind. 485 lift on stock springs and uncut guides is too much.