checking valve clearance with head off?

Is it possible? I have my head off and the valves and seats were cut, and I would liek to get the clearances so I can order the shims now as I don't have the block yet. However, is there any way to spin the camshaft?

Thanks

when i did mine i used a screwdriver very carefuly on the teeth and pried it around .Then I used a wrench on the bolts on the cam sprocket but you have to watch out when the cam lobe comes off the center line because it will spin the cam from the pressure of the valve spring.

Trav wrote:

Is it possible? I have my head off and the valves and seats were cut, and I would liek to get the clearances so I can order the shims now as I don't have the block yet. However, is there any way to spin the camshaft?

Thanks

YES THERE IS
Check the filebase section, wiredgeorge posted how to do this. But it is for the 900-1000 models and you measure the valve stem height. It was taken from the Kaw Shop Manual, maybe your models' Shop manual has the same information?

Post edited by: OKC_Kent, at: 2006/05/10 14:13

Turning on the camshaft sprocket bolts works. Just a word of caution, only have ONE camshaft bolted in at a time. If you are turning one while the other is stationary you will jam the intake and exhaust valves together on one cylinder whichever happens to be open on the stationary camshaft. (How do I know? 'cos I'm a thickheaded SOB and actually did it twice. One time no foul, the other time bent a valve.)

OKC_kent, I got a PM from "duck" with the same information. I replied this to him.

Hm. My cylmer manual gives a dimension for stem height like that, and it must be below it, otherwise the smallest shim availible would probably be too big, it says.

They give a forumula to figure out the shim to use, using the clearance desired, the clearance measured, and the current shim size.. but nothing between the two.

All my valves are just under the max stem height, some by only a few 32nds of an inch. The highest ones shim out ok with a 2.25 shim, and they go to 2.00, so I'm sure they will all shim out ok. It's just a matter of what that is exactly.

I only have one cam in right now (just seemed like a good idea, plus I'm lazy) but thanks.. I will definitely remeber that!

The only thing I would worry about is breaking the torque on the bolts (or over-torquing them, depending on which way you go) but I guess I could always just re-torque them afterwards.

Very interesting thread. I just paid extra to have my head "bench shimmed" after major head work, so I know it can be done. I never thought of just how they might do it! I've shimmed the head on the motor plenty of times, but never off. Turning the cam is definitely the trick to that. I wanted mine bench shimmed so I could at least have a good idea of where to start with the shims because everything is brand new. Hopefully it'll be right on when I bolt it in. Good Luck!

lots of machine shops wont shim heads unless motor is together so things dont change when head is torqued down.

wireman wrote:

lots of machine shops wont shim heads unless motor is together so things dont change when head is torqued down.

Not sure what you mean here...the clearance between the top of the shim and the heel of the cam doesn't change when you bolt the head to the bottom end.

I use a large flat blade screwdriver to rotate the cam sprocket with pry points on the cam chain valley - being careful not to "fold over" the rocker cover surface.I have never turned the cam with the sprocket bolts and would be worried about breaking one off in the cam flange.Once they break,the cam is a paperweight. Bench shimming saves a ton of time compared to on the bike.

when sid pogue used do stuff for us back in the stone age he wouldnt adjust valves on heads unless it was on a comlete motor.i always thought it had something to do with things moving around when head was torqued down kinda like using a torque plate when boring a car engine block because the bores get distorted from torqing down head.a certain motorcycle builder that used to be here in town whos name cant be mentioned (i think hes in witness protection program now!:whistle: )would shim them close on the bench but would always say to check them again once head was on motor.

wireman wrote:

when sid pogue used do stuff for us back in the stone age he wouldnt adjust valves on heads unless it was on a comlete motor.i always thought it had something to do with things moving around when head was torqued down kinda like using a torque plate when boring a car engine block because the bores get distorted from torqing down head.a certain motorcycle builder that used to be here in town whos name cant be mentioned (i think hes in witness protection program now!:whistle: )would shim them close on the bench but would always say to check them again once head was on motor.

I think you're right Wireman, my builder also told me that even though things were "bench shimmed", the clearances definitely might change when the head is bolted down. Bench shimming is no guarantee that the clearance will be exact, but at least I'll be very, very, close. If I ever get the darn thing together, that is, but that's another story

You always want to bench shim them after a valve job. If yoe is too tight or too loose, you want to find out before you put it on.

Jay