Valve Adjustment

When the bike is running there is pressure fed oil holding the cam in the center of the journal clearance.

Nessism wrote: When the bike is running there is pressure fed oil holding the cam in the center of the journal clearance.

You'd think if the oil pressure did not hold the journals centered, you be burying one, every stroke, in the babbit and wiping it out.
When the engine is not running... it seems like all the oil could squeeze out if the cam flexes a bit.
Interestingly, when I dry fitted one cam at a time and check shim clearances, they were a solid half thou off from the two points discussed.
Before I put my top end back together, I also used plastigauge (dry) to see where they all were and actually had two bearing sets that were a little big, so I put four new bearing halves in the head.... others were good.
I wish I would have remembered if those shims were the ones that were a half thou off....

If someone thinks the cam is flexing their just fuckin stupid.
Put a cam in a press setting on two side by side bearing journals
with a dial indicator and see if it flexes before it breaks.
Cast iron does not bend.

The cam is not flexing enough to matter. It's moving in the journal clearance.

If the cam is moving in the journal it's making metal to metal contact
goddamn listen to what you're saying

zukdave wrote: If the cam is moving in the journal it's making metal to metal contact
goddamn listen to what you're saying

Maybe you should calm down and try measuring it both ways yourself sometime. It's not a huge difference, but it may make the difference between one shim size and the next, and that could really matter if you're on the low end of the clearance range. I don't think Kawasaki developed the procedure just to piss you off.

zukdave wrote: If the cam is moving in the journal it's making metal to metal contact
goddamn listen to what you're saying

The journal clearance is what? .003" or so?

What do you think happens to the cam sitting in the journal clearance when the adjacent valve is pushing up? Answer: the cam is pushed up so it contacts the cam cap bearing surface. So instead of there being .0015" clearance all around the cam like it will be when running, the cam has literally 0 clearance at the top of the cam, between the cam cap, and .003" clearance at the bottom of the cam, between the journal in the head. Use your 180 degree measuring method and the measurements will be off by about .0015".

This time around I put in new bearings. I tried adjusting both ways. There was a slight difference. Not much but it was there. I do it two at a time now. The cam isn't flexing, it's the clearance in the bearings.
Steve

Nessism wrote: By adjusting the valves in pairs the adjacent valve is on the base circle as well as the valve being adjusted.

The FSM I posted is from the 750 twin. I don't believe there is a point of cam rotation on the 750T where both valves are on the non-lift portion of both cams at the same time, at least that's what I found when assembling the head. If there was a spot, it would have made assembly easier. Maybe that's why they use the 180-away method for adjusting valve clearance.

As for "false clearance readings", I have seen them when I accidentally released cam chain tension when rotating the engine using the 17mm wrench by reversing direction of rotation to get the cam lobe "centered up" pointing away from the valve. It is, as somebody else stated, due to up-down play the camshaft has in the journals. With full tension on the chain, it minimizes clearance. And worst case, it can vary a couple of thousandths.

And I did check clearance in every cam journal with plastigage, all were nominal.

I just check mine at tdc for each piston

bountyhunter wrote: As for "false clearance readings", I have seen them when I accidentally released cam chain tension when rotating the engine using the 17mm wrench by reversing direction of rotation to get the cam lobe "centered up" pointing away from the valve. It is, as somebody else stated, due to up-down play the camshaft has in the journals. With full tension on the chain, it minimizes clearance. And worst case, it can vary a couple of thousandths.

This may have been the problem I currently have. I checked clearances a couple months ago, using the 180 method. Pretty certain I reversed direction while trying to moved valves into place.

I'll be pulling the bike apart tomorrow to check, I've been having a pretty noticeable tick/knocking in the case, that resembles the problems in this thread.

Have you synced your carbs?
Steve