TAPPET CLEARANCE 78 GS1000

[renobruce]

I checked my cam lobe to tappet clearance on the GS1000 as per the manual. My feeler guage only goes down to .002 in. Most of the valves fell between .002 and .003, which is good. The others I could not get the feeler guage under (tighter than .002). However, when I would try and rotate the bucket/shim, they would spin around easily (no drag), which to me meant that there was SOME clearance between the lobe and shim. Am I safe to assume that the valve is closing all the way? I know looser is better than tighter, but if the valve is seating all the way, I should be good.... right?

[SqDancerLynn1]

It would be safe to ride but it NEEDS adjusting

[renobruce]

I suppose that once it warms up, I might loose my clearance if it's too tight?

Anyone know where to get a feeler guage that measures .001 inches?

[nert]

I suppose that once it warms up, I might loose my clearance if it's too tight?

True to a pushrod and rocker arm design. But, I have pondered that question. Due to the overhead cam design and aluminum head, steel valves, etc. Aluminum expands greater than steel, would the head expansion not RAISE the cam lobe higher above the valve??? Increasing clearance? I don't know for sure, seems it would to me. This is the type of thought that always gets me in trouble on this forum.

SnapOn has a .0015 gauge. Sears did at one time, don't know if they still do.

[Sandy]

If the .002" gauge won't go in and the shim is rotating chances are the clearance is either alright or slighly tight. What I do in this situation is install one size thinner shim and then check the clearance and usually it will still be within spec and just leave it in there. Just a guess but if the .002" gauge is a tight fit the clearance is probably around .0015" and if it won't go in at all it's probably .001" or less. Better to run them on the loose side of spec rather than risking it getting too tight.