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Discussion Starter · #1 ·
Actually 2 questions. Easiest way to pull rocker pins or just buy the 50.00 tool.
2. Using the loaded and unloaded method. If you go to a thicker shim on the unloaded measurement wouldn’t that also affect the loaded measurement.
Sorry for the stupid question but I’m adjusting my valves to LT’s spec’s this time.
 

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Using the loaded and unloaded method. If you go to a thicker shim on the unloaded measurement wouldn’t that also affect the loaded measurement.
Yes, no, not really. You're looking for the difference on the loaded check to find the closer clearance.

If you measure .008" unloaded and .010" loaded, you're looking at a opening clearance of .008" and a closing clearance of .002"

Loaded - Unloaded = Difference / Closer clearance. Opener clearance is simply the unloaded measurement.

Lets say for the sake of this example you're shooting for a opening and closing clearance spec of .004" for both.

If you tighten up the opener clearance first, you simply use a shim .004" larger than the one currently in there that is giving you the .008" clearance.

Once you've installed that .004" larger opening shim, you measure again and now find .004" unloaded and .006" loaded.

So yes, your unloaded and loaded measurements have changed, but the difference is still .002" and therefore your closer clearance has not changed and closer clearance is what you're after with the loaded measurement.

On to the closer clearance. It's still .002" after the opening shim change and you're going for .004". Install a closing shim that is .002" smaller than the one currently in there.

Once you change the closing shim, measure again.

You will now see a unloaded clearance of .004" and a loaded clearance of .008". This means you're at the target spec. .008" Loaded - .004" unloaded = difference / closer clearance of .004".

On the other hand, if you're one who likes to change the closer shim before the opener shim or one who changes both shims at once then there will be variations in what you read. Just remember the only reason you do the loaded measurement at the opening rocker is to find the closer clearance. If you could easily get a feeler gauge between the cam and the closing rocker, there would be no need to do the loaded measurement at all.

Hopefully I haven't confused you here!
 

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Here's my rocker pin puller.

It's an M5 x 50 .8 pitch bolt passing through a 10 mm socket with a washer and wingnut. Or you can spend the $50.
Just want to let you know that you'll probably need a slightly larger socket. I grabbed the wrong size. The socket has to be big enough to let the rocker pin be pulled into its recess while you tighten the wingnut. Sorry about that.
 

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Discussion Starter · #5 ·
Thanks for the fast responses and no I’m not confused. Going to order my shin kit from EMS and get to work, keeping my fingers crossed that I have no bad rockers at 29000 miles.
 

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Discussion Starter · #6 ·
UPDATE and a couple of questions.
Pulled the cams and found one bad rocker on the horizontal exhaust, not bad at 29000 miles I thought. All my clearances were within Ducati’s spec’s but adjusted to LT’s.
Checked last two valves on the horizontal exhaust and measured.013 and .011 with a loaded clearance of .014 and .012
Isn’t that a little unusual sense the rest were only off a couple of thousands ?
There must be a easier way to check the vertical exhaust valves or is there?
As far as the half rings go how do you tell which way they go back in the closer shim or should I use new ones?
Thanks again
 
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