Valve Lash Measurements

Took the following (averaged) measurements today, 5000 miles since the head/cams were installed on March 19
3 Ex shim was changed from 250 to 255, which was near the upper spec. limit according to the FSM.
All exhausts were within .010+/-mm of measurements shown, while the intakes remained consistent through several repeated checks.

Any comments for me to consider before closing it back up?

Looks fine to me.

Glad to see this. Maybe the ones that refuse to do their valve adjustments will do them now. :lol: Good job.
Steve

I'd be happy with that, especially when the engine is blazing hot on the middle of the summer on a +90° day!!

Side note: I didn't think to loosen the APE tensioner before removing the cam cover bolts. Seems it didn't matter though, because the chain was not pressing against the guide inside-under the cover, even after the gasket was removed. :huh:

Maybe the chain tension was a little loose, but it wasn't slapping around that I could tell

daveo wrote: Side note: I didn't think to loosen the APE tensioner before removing the cam cover bolts. Seems it didn't matter though, because the chain was not pressing against the guide inside-under the cover, even after the gasket was removed. :huh:

Maybe the chain tension was a little loose, but it wasn't slapping around that I could tell

One of the reasons people use the manual tensioners is because you don't have to loosen them when you remove/install the valve cover... Only the automatic tensioners have that requirement.

jackleberry wrote:

daveo wrote: Side note: I didn't think to loosen the APE tensioner before removing the cam cover bolts. Seems it didn't matter though, because the chain was not pressing against the guide inside-under the cover, even after the gasket was removed. :huh:

Maybe the chain tension was a little loose, but it wasn't slapping around that I could tell

One of the reasons people use the manual tensioners is because you don't have to loosen them when you remove/install the valve cover... Only the automatic tensioners have that requirement.

assuming you mean cam cover, why is it necessary to release the cam chain tensioner when removing the cover?

It's not about removing the cover, it is about installing the cover. The cover is part of the chain guide system. It pushes down on the chain in between the cams. If take out all of the slack, then install the cover, you are stretching the chain, and/or forcing the tensioner to retract, which it was not designed to do. You end up, at best, with extra chain-stretch, extra stress on the cams, and in bad cases, possibly broken guides, or broken tensioner, or broken cams (haven't seen a broken cam on a KZ, but did see it on a Yamaha).

Another reason to follow the directions in your MANUAL.
Steve

Later bikes had a chain glide built into the covers that did exactly that. They contributed to the tension on the chain.

Older models, like my 1977 KZ650 didn't have those new-fangled devices. :laugh: Instead, they had an idler sprocket on top of the cylinder head.

So depending on which model you have you either do or do not need to fiddle with the tensioner when removing the valve cover. To be safe, consult the manual for your specific model. Ed