Tight valves- all 8 less than .002

[scoot]

I have this 1980 motor that obviously needs thinner shims all around. My thinnest feeler gauge is .002", and it does not slip under any cam. I suspect there is zero clearance. Yes, the lobe is opposite the lifter when gauged.

So how should I proceed? I'm thinking to pull the cams and read all the current shims, source a shim thinner than any installed and test it for a measurable clearance. Or is there a straighter path to correct valve clearance?

scoot

[BA80]

I just went through some vave adjustment issues ( my stupidity) yesterday. You need to get some clearance measurements before you go changing shims or you won't know what to put in.

I used my Motion Pro tool and it worked flawlessly. But, to each his own.

[crazy steve]

I've found that they rarely get to zero as the motor will start running poorly before that happens. The minimum they seem to get to is about .0015". So work from that assumption, you might have to go back and re-shim a few but that should get you close...

[crazy steve]

I'll add that you should see a healthy increase in compression after the adjustment...

[scoot]

I just went through some vave adjustment issues ( my stupidity) yesterday. You need to get some clearance measurements before you go changing shims or you won't know what to put in.

I used my Motion Pro tool and it worked flawlessly. But, to each his own.

Well, that's the thing... can't measure them with even my thinnest gauge. Crazy Steve (thanks, Steve) sez try estimating at.015. Good as any plan, I guess.

I got that MoPro tool, will start with that just to see if I can get it to work. I'll prob. grind it a bit and go real easy with it.

scoot

[BA80]

Well, that's the thing... can't measure them with even my thinnest gauge. Crazy Steve (thanks, Steve) sez try estimating at.015. Good as any plan, I guess.

I got that MoPro tool, will start with that just to see if I can get it to work. I'll prob. grind it a bit and go real easy with it.

scoot

Any plan is better than no plan. A good place to start.

Have you ever had this engine running?

[scoot]

This engine runs really well. as you can guess, no valve racket at all. Starts quick, idles at 1100 rpm real smooth. Fast throttle response, no hesitation. Has about 55k miles, apparently eats about a quart of oil per 1000 miles.

scoot

[BA80]

This engine runs really well. as you can guess, no valve racket at all. Starts quick, idles at 1100 rpm real smooth. Fast throttle response, no hesitation. Has about 55k miles, apparently eats about a quart of oil per 1000 miles.

scoot

Something doesn't sound quite right here...........no clearance?

[scoot]

Ya, clearance is less than .002" Maybe .0015", I cannot measure that thin.

scoot

[ddragon63]

Highly recommend grinding tool like this... help fit it in there 4 times faster. YMMV but I wasted 15 minutes on my first one. finally ground it and too me 15 to do the next 4 together.

[BA80]

Ya, clearance is less than .002" Maybe .0015", I cannot measure that thin.

scoot

It shouldn't run for crap that way is what I'm saying.

[scoot]

Ya I get that. I'm thought I was doing it wrong, but there's not many ways to gauge them. Anyway, I can borrow some thinner gauges tomorrow, maybe that'll get me some numbers.

And thanks for the pic, Dragon. I need that.

scoot

[ddragon63]

trust me just do it... it will fall right into place with out creating new words once you remove a little off the face side... I threw mine across the garage twice before going to the bench grinder with it.

[bikerphil]

What I would do is take each shim out and write down the number. Then I would go 2 sizes smaller on the intakes and 4 sizes smaller on the exhausts. That should be just about right assuming all your clearances are between zero and .002". You might be able to swap some around that you already have. Members here have shims they will swap with you and new ones can be found here....

http://www.newmotorcycleparts.com/mo...lve_shims.html

Remember, each shim step is .002"

[scoot]

Thanks, Phil. Good plan. Good sources.

scoot