Ducati.ms - The Ultimate Ducati Forum banner
  • Hey Everyone! Enter your bike HERE to be a part of this months Bike of the Month Challenge!
1 - 7 of 7 Posts

·
Registered
Joined
·
173 Posts
Discussion Starter · #1 ·
Hey everyone,

Bike in question:
1995 900SS/SP

Question about horizontal opening shims being .02mm too loose / gap too large

Every other opener and closer on the bike is now within spec, after a few swaps.

My process:
  • Pull the belts
  • Remove openers on both inlet and exhaust
  • Check closers first
  • Check openers with both inlet and exhaust installed; check the side opposite the side that is engaged / pushing down / rocking
I have a shim kit, but the next shim up won't allow a .10mm (.06 will fit) and the next size down takes me out to .16mm

Haynes reminds me that my acceptable range is .10 – .12mm

So I'm calling it a .14ish, which is .02 too loose.

I put around 3k a year on her commuting; city and highway mileage, no tracking.

Waiting for new belts and gaskets to arrive, BTW.

Anyone see any issues?
 

·
Just Visiting Your Planet
Joined
·
10,443 Posts
I have a shim kit, but the next shim up won't allow a .10mm (.06 will fit) and the next size down takes me out to .16mm
You can lap shims down with 400 grit and a little oil. I use a thick piece of glass underneath so it's perfectly flat.
 

·
Registered
Joined
·
58 Posts
Yes, 400 grit black wet and dry paper and wd40 for me, turn the shim often and about 45 secs removes a thou.

Make sure you wash the shim with brakeclean and dry before re measuring, carborundum in the engine is not recommended by the manufacturer....
 

·
Registered
Joined
·
173 Posts
Discussion Starter · #4 ·
To extend the discussion a bit…

What are the repercussions — if any — of running for another interval (6,000 miles) with openers that are .02mm too small?
 

·
Retired Pipe Polisher C2H6O+
Joined
·
19,081 Posts
According to LT Snyder’s book Ducati’s specs are 0.05 - 0.12mm on intakes and 0.05 - 0.15 on exhaust.




Sent from my iPhone using Tapatalk Pro
 

·
Registered
Joined
·
171 Posts
You can lap down the next size up ship to get it exact. But honestly I’d go with the .02 undersized shim and call it a day. Opening valves tend to get tighten up over time


Sent from my iPad using Tapatalk
 

·
Registered
Joined
·
3,647 Posts
i wouldn't go under 0.10mm. ime the openers only get tighter when the valves are moving in, and you'll see corresponding loose closers. i find they both open up, closers as the collets settle/wear and openers just a little.

you can rub them down easily.
 
1 - 7 of 7 Posts
Top