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Valve Clearance Measurement (Head Dissasembled)

Wez_

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Location
Enfield, CT
1982 CB750 DOHC

The head is removed, awaiting new head gasket. So I am preparing the valve clearances and want to know how to mock these parts up.

Head has valves, springs, shim bucket installed.

Can I simply install each camshaft in the correct position (using the small mark on the right side of the camshaft aligned in the 12, 3, 6 and 9 o'clock positions)?

Bolt down the camshaft holders and measure the clearance for both intake and exhaust cams?

I assume rotating the cam to be in it's optimal position would require leverage and the valves will slightly open when the cam holders are tightened.

Is there a better way to do this with the head removed and disassembled?
 
Far better to be using lighter springs so can turn it easily by hand. But then it has to come apart again. Will be hard to turn it over like it is now. But yes you can do that. When I use the race checking springs I can turn it all by hand.

One cam in at a time, if both are in you can ram one valve open into another and easily bend them, the valve axis lines cross each other.

You MUST have shims in place at all places, turning cam against a no shim tappet WILL damage parts.
 
Ok, so i ran into an issue...

The intake camshaft doesn't have an indicating notch cut into the end of it. So i cannot tell where to position the camshaft to measure clearances. Normal clearance instruction have the two camshafts connected via the chain and they rotate together in the correct position.

Is there a way to position the camshaft correctly by eye?
 
I never use those marks. I move the lobe highest tip exactly 180 degrees opposite the cam contact point at the tappet shim, you are then firmly on the base circle of the cam and safe to set it there. No need to measure, an eyeball is fine.
 
You by some weird thing don't have marks on the other end do you? Odd to not have marks there. Meaning cam in backward?
 
20170605_064345.jpg

This little notch only appears to be on the exhaust camshaft right side.

Intake cam only has the white paint mark. Other end of the intake camshaft has the two square cut outs on the left side. (not sure of there purpose)
 
Could be a replacement OEM cam....................anyway, don't need the marks, they are sorta a waste anyway due to the spring pushing cam around thing and why we use .005".

Forget that mark. Do per post #6.

http://www.lunatipower.com/Tech/Cams/CamProfileTerms.aspx

First pic. You want the very middle of that base circle thing at the shim contact point. At the 'C' of Base 'C'ircle...............
 
Got it! The intake sprocket two alignment notches (to the top of the cylinder head) when aligned, placed the base circle of the camshaft in the correct position for both 1-3 and 2-4. Just had to rotate the cam 180*, then use the two sprocket alignment notches again.

Now I'm playing musical shims.
 
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