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Hi, I have a 1997 748 and am currently doing the valve adjustment. This is my first time to adjust the valves myself and am currently working on the vertical intake side valves first (easiest access).

I have been following ducatitech.com's online guide http://www.ducatitech.com/2v/maint/adjust/index.html.

The unloaded gaps seem to be fine (~.002").

The question is how much force am I supposed to press down on the closing rocker arms to check for the loaded clearance? I pushed down on the closing rocker arms with a flat tipped screwdriver and they wouldn't move at all.

Does this mean my closer clearance is too tight? If so, how would I calculate the thickness of the shim to get to make it to the correct clearance?

I'm pretty sure I am at TDC on the rear cylinder (I double checked with the flywheel mark to the first dot-horizontal TDC, then I turned it approx 260 degrees for Horizontal TDC).

Any help/advice would be greatly appreciated! :)

Larry.
 

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I recently just got done w/ my first valve adjustment and am by no means an expert, but when I pushed down, it was more like a click rather than actual movement. But there should be a little bit of movement.
 

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I'm sure there are many that would disagree, but I find it MUCH easier to measure the closers at the follower/cam behind the cam, with a set of long, curved feelers. No need to do the push-against-the-spring thing, which I never felt comfortable trying to do with 2 hands. ;)
 

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I tried the direct approach as Old Baldy recommends, but my feeler guages were not long enough. I do the unloaded loaded method. You have to overcome the closer spring on the closer rocker arm. You should be able to feel when you over come the spring tension. After overcoming the tension, then you just want to apply as much force so the spring doesnt retrack back. If you apply too much force, you wont get the correct clearance as you can deform the rocker a few thousanths. I am guessing maybe 15 to 20 lbs of force maybe is optimum. Also dont jam the feeler guage in to get your clearance. Just slip it in with minimal force, otherwise you will again get the wrong readings. I have experimented and found I can slip a feeler guage .005 in too big if I really push on it. So it does take a certain feel. After you do it a few times, you kind of figure it out.

Mike
 

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ducatimike said:
I tried the direct approach as Old Baldy recommends, but my feeler guages were not long enough.

Mike
I use a pair of smallish needle-nose pliers to hold the feelers, which I bend to about 70 degrees in a smooth arc near the end. Works like a charm.
 

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Discussion Starter #6
HI guys,

Thanks for all the replies! Tonight I just removed the left side bearing housing for the cam, and pushed on the closer arms and they do move a little bit, but this is due to the unsupported cam shaft though. So that probably means that the closer clearance is .000" or maybe -.001"? This is probably not good huh?

I'll try to get some sandpaper/glass and sand the closer shim down, aiming for .002-.005" thinner.

What a great learning experience to work on my own bike. I just wanna say that those half rings are really "risky" to remove. I didn't want them to fall anywhere, so I put a dab of grease on them and a bunch of rags around it and that helped a lot during removal.

Thanks again for all the help.

Larry
 

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I think Desmotimes sells the longer feeler gauge sets for the 'old school' method everyone here uses
 

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Mike931 said:
I think Desmotimes sells the longer feeler gauge sets for the 'old school' method everyone here uses

That's a great site there is a bunch of tools I'm going to order from them.

So does anyone check the closers at the cam? Instead of doing a Loaded and unloaded reading? I'm about 4000 miles away form doing vavle checks on my bikes but I'm trying to get as much information about them as possiable.
 

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From what I’ve seen and read I don’t really think you have to do the load unload method. Do your feeler guage checks on opener and closer positions on the cam. If it’s within spec, woohoo! If not the write down what you get. Then use the calculation from the posted images im putting up to figure out what shims you need to get. Of course you’re gonna need a shim measuring tool to figure out what new shim you need
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