Topic: Valve Adjustment

[BoCoJohn]

Has anyone else noticed that the Valve adjustment table in the Maintenance Operation section of the 1973 CB500 manual is incorrect - I think?

Under the heading: 1. TAPPET ADJUSTMENT, paragraph 6 is a table that states when the No. 1 cylinder is at TDC of the compression stroke you adjust:
inlet and exhaust of No. 1
exhaust No. 2
and inlet No. 3

when I think actually you adjust inlet and exhaust No. 1 and  inlet No. 2 (instead of exhaust) and exhaust No. 3 (instead of inlet).

Does anyone know which is correct?

[Deltarider]

The table is right.

[JBMorse]

I can't remember exactly but I think there was a typo in either the table or the text that showed one incorrect valve.  The easy way is to remember is to turn the crank as instructed, then adjust the valves that wiggle.  You should be able to move all the valves you're adjusting ever so slightly.  Then turn the crank 360 degrees and adjust the valves that are now wiggling. 
And of course make sure the lock nuts are all tight after.  I once left one loose and it came off and was rattling around in the valve cover for a while

[MCRider]

table is correct: If 1 then 2ex, 3in; If 4 then 3ex, 2in.

Checking for the clicking valves works with the infrequent but possible exception that if a valve has tightened rather than loosend, it won't click. A tight valve would indicate other problems, the valve, or seat, has settled, and the valve is possibly burned. The more likely cause is a poor prior adjustment, the valve lash tightened up when the lock nut was turned and the mechanic didn't catch it.

[JBMorse]

table is correct: If 1 then 2ex, 3in; If 4 then 3ex, 2in.

Checking for the clicking valves works with the infrequent but possible exception that if a valve has tightened rather than loosend, it won't click. A tight valve would indicate other problems, the valve, or seat, has settled, and the valve is possibly burned. The more likely cause is a poor prior adjustment, the valve lash tightened up when the lock nut was turned and the mechanic didn't catch it.

Hmmmm really?  Now I'm wondering if I've been adjusting that one tappet wrong.  Next time I do and adjustment I'll pay very close attention to this.

[dave500]

i allways do each cylinder on its own compression stroke anyway,follow the firing order as you go,that way you WILL have the cam at the base circle,even on diesel trucks ill do it the "long way".

[Whaleman]

I have always just turned crank until #1 intake goes down then up and continue to T1-4 then do #1. Then turn until #2 intake goes down the up and continue to T2-3. I just do 1 cylinder at a time. Has always worked and no charts to remember. Dan

[Deltarider]

I have always just turned crank until #1 intake goes down then up and continue to T1-4 then do #1. Then turn until #2 intake goes down the up and continue to T2-4. I just do 1 cylinder at a time. Has always worked and no charts to remember.

That's indeed the best way.

[tlbranth]

Put the book away. When #1 intake is all the way open, adjust #4 intake.
                           when #1 exhaust is all the way open, adjust #4 exhaust

etc.

1 & 4 are opposites.  2 & 3 are opposites. When a valve is fully open on one, its counterpart is fully closed on the other and can be adjusted.

This'll work for any inline 4 engine that I ever saw.

[Mark M]

Cross plane cranks are a little different though  

[dave500]

Put the book away. When #1 intake is all the way open, adjust #4 intake.
                           when #1 exhaust is all the way open, adjust #4 exhaust

etc.

1 & 4 are opposites.  2 & 3 are opposites. When a valve is fully open on one, its counterpart is fully closed on the other and can be adjusted.

This'll work for any inline 4 engine that I ever saw.

the cam still wont be fully on the base circle as its just finished closing,on the compression/firing cycle you can do both valves and they WILL both be clear from the ramps for sure.