valve inspection question

What is your largest feeler gauge?

Does the bike have good compression?

My largest feeler gauge is a .20 motion pro. The compression seems good, but I have not used a guage on it. It seens to have plenty of power. I do have a set of different automotive feelers but they are too wide to fit.

So, then, because you didn't actually measure it, you don't know what the clearance originally was, only that it was larger than .20mm (about .008").

Without getting too far side tracked, how did you check your exhaust valves if the biggest gauge you have is .20mm?

Regardless, there are 5 things that come to mind that would account for excess clearance. (actually 6, but we're going to assume that you already know that the exhaust valves are the two in front of the head).

> Incorrect assembly. The wrong shim was put in place to begin with.

> Wear at the cam carrier cap.

> A valve is bent. (You would loose compression)

>A valve is sticking or being held off its seat by carbon, or other debris. (compression loss again)

> Wear at the lifter or lobe (rather unlikely)

Tap the lifter a couple of times to bounce the valve on its seat and encourage it to shut all the way, then recheck the clearance.

If nothing changes, you need to look the cam cap over for the problem in item two.

After that, I suppose you simply need to go to a 190 with it. I never have any trouble using normal 4" automotive feelers in a 450. You might look into a set of them.

For each shim size .05 you should pick up .0015 you should have picked up at least .003in.

.05 mm = .00197"

The problem still is that he doesn't really know what he started with.

.05 mm = .00197"

The problem still is that he doesn't really know what he started with.

That is just a little over.0015 and we are talking A BLANK HAIR. I rounded down, COME ON.:thumbsup: ONE IN A HALF THOUSANDTHS,just to make it simple.

Correct everything is thrown out of the window if his beginning measurement is in the air.

That is just a little over.0015 and we are talking A BLANK HAIR. I rounded down, COME ON.:thumbsup: ONE IN A HALF THOUSANDTHS,just to make it simple.
If you're rounding, it's a whole lot closer to .002, wouldn't you say?
If you're rounding, it's a whole lot closer to .002, wouldn't you say?

Definetly closer,but when I SHIM I have it in my head that 1 shim size down or up (with a hot cam kit,not Yamaha's shims)is .0015in I do not use the chart in the service manual. It is just easier for me saying 1 shim size is .0015 instead of almost .002. I like to think 1 shim isnt going to give .002in clearance or tighter. I know it will,but I am stuck on the .0015. Leave me alone:ride:

I like to think 1 shim isnt going to give .002in clearance or tighter. I know it will,but I am stuck on the .0015. Leave me alone:ride:
Admitting it to yourself is the first step.
Admitting it to yourself is the first step.

I like myself,people like me,and gosh darnit I am good enough.:thumbsup:

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