Setting valves on the bench

[nitro3custom]

I'm taking apart the head to see if the seats need any work or just a good cleaning and lap job. When I get my new cams would it make sense to set the valve shims while on the bench? That way it will really be, bolt it on set cam timing and done. I know that the cams have to come off when I put the head back on. but that shouldn't have any effect. Thoughts?

[Testarossa]

It should get you close. I think that there may be some small variances with the head installed due to the torqued head and tension of the cam timing chain.

[koolaid_kid]

Absolutely set them on the bench. They will change slightly when on the bike , but all you have to do at that time is calculate the delta.

[hampshirehog]

Why not do it when the motor is back together in the bike? I can't see why you would want to put the cams on and then take them off again.

[nitro3custom]

That's pretty much what I was thinking. And I forgot to mention I'm doing this on the dinning room table, and the wife is giving me looks. If you don't hear form me soon. call 911. thanks

[sharpy]

Yes, that be a wise way to do them. But only have the cam in one side at a time as u will touch some valves it both cams are installed and ure turning only one side to check clearances. Oil everything slightly and it be easier if the head was sitting in some V-blocks and the kitchen table isnt the right area as it does get a little messy.

[koolaid_kid]

You do them on the bench first because it may take 2-4 swaps to find the correct shim. Once they are dialed in on the bench and you do them on the bike, it should take 0-1 swaps to make them correct. Personally, I find it easier to swap shims on the bench than on the bike. But that's just me, I'm not elastoman.

[blowerbike]

bench shimming is the shlt!
especially if its a shim under set up.

[Nessism]

I did shims on the bench and it was a pain. For one thing it's difficult to turn the cams in order to check valves, and another thing is the head needs to be supported so the valves can open and not get bent. No huge big deal mind you, but it sounds easier in theory than practice.

[Suzuki_Don]

Take it from me do it when the head is on the motor, much simpler that way. Changing shims with the head in place is a breeze with a few cable ties, small screwdriver and long nose pliers.

[blowerbike]

I did shims on the bench and it was a pain. For one thing it's difficult to turn the cams in order to check valves, and another thing is the head needs to be supported so the valves can open and not get bent. No huge big deal mind you, but it sounds easier in theory than practice.

head stands and valve shimming tools go a long way

[mighty13d]

head stands and valve shimming tools go a long way

How does this help anything? Concentration maybe?

[bwringer]

The rest of the engine makes a very nice cylinder head holder.

Almost as if they were meant to be together or something.

There's even a nifty built-in way to turn the camshafts and everything.

And FWIW, the motorcycle frame makes a pretty nice engine holder for the same reasons.



Anyhoo, there's little point to attempting this on the bench -- you might easily bend a valve as noted above, and turning the camshafts is a royal pain. Plus, you end up installing and removing the cam caps one more time than needed, and we all know how &%$#! delicate those bolts and threads can be.

It is, of course, worthwhile to write down exactly what shim is in each one.

[rapidray]

Terry & I are both engine builders & KNOW it is easier to shim them on the bench. You use a wrench to turn the cams with the sprocket bolts. My set of head stands get the crap used out of them, as I'm sure Terry's do too! Guys, when we tell you some of our engine building "tricks" once in awhile, you might just want to stop & ask yourself if we MIGHT just know what we are talking about. Ed was right in that if you don't have head stands it can be more difficult but you can buy stands cheap, or make a set even cheaper! Ray.

[blowerbike]

How does this help anything? Concentration maybe?

its very simple.
i would rather work on engines or cyl. heads ect... on a bench rather than being bent over reaching through frame tubes.
this question is talking about a head that is off of the bike already...not removing the head to service it.
PLUS.....
if you run into to any problems such as bad threads ect...
this is much easier addressed with the head off the engine.
wouldn't a person rather have a head that could be bolted on/set the cams/button up and fire??
when i was doing a lot of work i would have my people adjust the valves on shim types after they did a valve job for me(bench shim).
time was money and the little they charged to shim a head was well spent so that i could put the top end back together and move on to the the next job.