Shim problem

[AliDL]

Hi all, 750ie vertical cylinder inlet closer, shim measuring 6.95 getting a clearance of .12mm, have larger shim which I’ve sanded several times and fitted but is still binding. I’m down to 7.02 -03 on replacement shim still binding…don’t get it. Belts are off openers both sides off, the keepers are back in same orientation, have new keepers but these look ok. I’ve followed all the videos and advice on here many times, for other shims no problem.
I’m slightly confused why it’s doing this?
Tried the 6.95 shim no binding plenty clearance. Slightly frustrating at this point,

 

[AliDL]

I did position the cam for maximum clearance, when measuring the inlet closer, I felt the exhaust rocker arm just want to move downwards as in Brad the bike boys video.

 

[Dukedesmo]

You're measuring the outside, the 'working face' of the shim that sits against the retainers is inside the 'thin end' of the shim.

You need to use a measurement tool that sits inside the shim to get the true reading.

 

[AliDL]

You're measuring the outside, the 'working face' of the shim that sits against the retainers is inside the 'thin end' of the shim.

You need to use a measurement tool that sits inside the shim to get the true reading.

I’m using a 3mm measuring tool which I zero the gauge on. It’s a Kawasaki shim.

 

[Dukedesmo]

Apologies, I didn't see it - appears to be totally inside the shim.

I have a couple of different measuring tools but they are 10mm and 15mm respectively, they are Ducati specific so I wonder if yours is sitting on the correct surface?

Are the shims identical internally, is it possible they were machined slightly differently internally making them sit different?

What are the retainers like? I understand if worn they can make a difference, I have the MBP collets in mine to avoid any discrepancies and broken half-ring shenanigans.

 

[AliDL]

The 3mm Kawasaki shim/tool is a good fit onto the inner shoulder of the Ducati closer, and seems to give uniform measurements, I wonder if the shim on the right I’m fitting which is used has wear to the shoulder which the tool doesn’t seat on but the keepers do seat into fully, I’ve always thought the shoulders on closets look indented by the pounding they get. I’m not sure the implications of this.
Viewing again the replacement shim doesn’t look indented as much on the shoulder, looks flatter than the current one which looks rounded indented.

 

[Dukedesmo]

One thing I have noticed is that, you often get slightly different readings when fitting, what appear to be, identical shims that measure the same on your measuring tool.

I suppose it's difficult to make them exactly the same so when you're looking for specific tolerances, you may need to try a few different shims to get what you want.

If you rotate the shim, does the clearance stay the same?

Also, whilst it maybe at the larger end of ideal, 0.12mm is still OK for openers IMO.

 

[AliDL]

thanks for that info again , that must be the case, differences in machining, strange the shim size had little relation to my measurements, lost count how many times I fitted that shim after sanding to eventually get a fit,
I was well below the shim size I was replacing, and still tight after looking closely at the machining, I did eventually get a fit with no binding late on last night! I also tried a couple other closers to compare against this Ducati phenomenon with no real conclusion that my measurements were out, I’m a bit wary of that shim, I may look for a other shims and alternative measuring tools, I need to learn more of this dark art..,