Valve lash / feeler gauge question

[Blue STreak]

In the past, I understood that the gauge which fit in fairly easily, and moved with just a light drag, represented the gap.

But I've recently been told that you can't compress the valve spring with a feeler gauge, and the thickest gauge that you can force in between the cam and bucket is the measure. This might be true for the thinner intake gap, but I can shove a .017 into the exhaust gap (on my ST1100), and it sure seems to be compressing the valve spring.

So the question is: how hard should I have to push the feeler gauge in? How much drag should there be on the gauge that accurately measures the gap?

Thanks much,


--
Bob Meyer, #1157, Fairfax, Virginia
'01 Candy Dark Red, "teSTarossa"

Youth is a gift of nature. Age is a work of art.
I'm a masterpiece. :-)

[Byron]

Bob,

You shouldn't have to FORCE the gauge at all. If you force things you run the risk of damage to the cam, shim or gauge which ever may be the softest. Here is what I do.

Choose a feeler and try and slide it in. If it goes in easily pick a thicker one and try again. As soon as I hit the one that won't go in, without force, the last one that went in is the gap. Also try and do it with the gauge level with the shim. If it's angled then you're adding thickness to the gauge. If you are having trouble with the feeler assembled in the group of feelers disassemble them and use them by themselves.

[Mongo]

+1 for Byron

[Blue STreak]

OK, thanks. That's the way I've always done it. Thanks for confirming it. The guy who gave me the contrary advice was knowledgeable enough in general to make me question myself.