So since fitting my new engine, it seems slightly "tickier" than the old one. Not terrible by any stretch, just not quite as smooth. So tonight I got my feeler gauges out and measured the valve clearances. They were as follows: -

Inlet (tolerance .005" - 0.007" according to Haynes)
.0045
.0045
.0060
.0060
.0060
.0045
.0045
.0045


Exhaust (tolerance .007" - .010" according to Haynes)
.0080
.0080
.0010
.0095
.0095
.0095
.0010
.0095

Now I've never replaced any shims before so I don't know a) how they would wear, and b) how much impact a given amount of variance will make.

So, given the above numbers, would that be enought to make it "tick"? Is it worth re-shimming?

Would I be correct in assuming that all the inlets with a clearance of .0045 essentially mean the valve is sitting further into its seat, and that's how they normally wear? How do we explain the exhaust, where some are at the opposite end of the tolerance (though still in tolerance). Have they somehow "worn" that way (if so what wears to make them go that way) , or perhaps just how they have been set?

I'm guessing that some have been re-shimmed in the past (guess I won't know until I remove cams and look at the shim markings), but does that sound likely? Or do they tend to wear at slightly different rates anyway?

Seems I've asked a lot of questions there - guess I'm just after some wisdom really, as Haynes deals only in cold hard facts, not real world experience!

Cheers, Simon

As they wear the tolerences tighten up, being above tolerence aint so bad but below is very dodgy, you need to address those asap. A tappy engine is a good engine. (only speaking from kwaki experience mind!) I ground mine down myself.

So I bit the bullet, removed the cams and re-shimmed as follows: -


Valve Clearances

Everything looking nicely within tolerance now. Oddly though, despite my calculations, most measurements seem slightly tighter than they were before, although of course a lot more consistent. Even the 3 I didn't change have got 1/2 a thou' tighter!

I measured after refitting cams and turning the engine a few times, but not after it's been running for a while so not sure if they "settle" a little afterwards?

Still, it sounds smoother now