Topic: CB750 valve/valve guide clearance question

[markb]

Does anyone know what the clearance between the valves and the valve guides is supposed to be on a CB750?  Or asked another way, what is the recommended OD of the valves and the ID of the valve guide?  Actually the manual says the ID of the valve guide should be .2599 to .2603”.  I don’t have a bore gauge that small but I have access to precision gauge pins.  A .259 pin goes in but the .260 one does not.  So I figure I have to be pretty close on that.  The manual shows pulling the valve out part way and wiggling it in two axes to measure the play with a dial indicator.  It’s supposed to be less than .003” for an intake valve.  My valve measured .2593” so worst case there should be .2600 - .2593 = .0007” clearance.  Does this make sense?

[Old Scrambler]

I am replacing the entire valve-train and rocker tower in my K3 after 72K miles.........the intake valve on #1 was worn and no adjustment remained at the rocker. I measured the replacement valves and guides as you did while still in the doner K1 head........very similar to yours. I then measured the K1 valves when moved to the K3 head and all were very similar for 'wiggle'room.  I did replace all of the seals and noted that the exhaust valves on the K1 had no seals on a very early motor number.  I was not the original owner but was told that motor only had less than 10K miles on it.

[bryanj]

It sounds good to me! do check the tip the rocker operates on for flat and remember THE CAN NOT BE GROUND ON THE TIP