Acceptable valve clearances ... which camp?

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fasterdammit
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Acceptable valve clearances ... which camp?

Post by fasterdammit »

I've read a bunch of marginally conflicting opinions on what the acceptable clearances are inside cylinder heads; some implying the vertical cylinder be slightly different than the horizontal, some saying get the exhaust closers to approaching .000, others saying ~.05mm is ok.

So, I know this has been beat to death here and everywhere, but I wanted to ask the question here, for myself, and poll the thoughts of my fellow Paso owners. Below are my measurements, but the one thing I haven't done is confirm the cams spin easily (w/o the belts engaged).

So am I reasonably assured thinking I'm relatively ok, here?

  • Vertical
    • Intake
      • Opener: .076mm / .003"
      • Closer: <.038mm / < .0015"

    • Exhaust
      • Opener: .101mm / .004"
      • Closer: <.038mm / < .0015"
  • Horizontal
    • Intake
      • Opener: .101mm / .004"
      • Closer: <.038mm / < .0015"

    • Exhaust
      • Opener: .152mm / .006"
      • Closer: <.038mm / < .0015"
My biggest concern is the opener for the exhaust on the horizontal cylinder. .152mm sounds a little out of spec. Possibly the intake opener on the vertical, too.

Are these acceptable?

Thanks in advance, all.
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Re: Acceptable valve clearances ... which camp?

Post by Finnpaso »

If i would be in Your trousers, i would adjust both, as its easy job... :thumbup:

If You take half rings away, put some ear plugs to oil channels, that half rings cant go inside engine... :)

Btw, did You remember to drive engine with high RPMs before adjusting, as valves MUST be CLEAR from shit before You start make adjustments? Adjusting only with cold engine!
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Re: Acceptable valve clearances ... which camp?

Post by Mc tool »

[quote="Finnpaso"]
If You take half rings away, put some ear plugs to oil channels, that half rings cant go inside engine... :)

Ha ha , I learnt this the hard way. I was reduced to tying a small fragment of a magnet to a piece of dental floss and dangling it down the hole, to no avail . Eventually I kicked her in the guts , went for a short ride and removed the sump plug , and there it was stuck to the magnetic bit on the plug .
I have found that if your closers are a bit loose ,it can pay to check those 1/2 rings as they do wear and replacing them can make the difference.
I set my closers at zero clearance , so that I can just rotate the shim with oily fingers. ducatitech.com has a short vid on how to do this valve clearance thing ..... worth a look
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Re: Acceptable valve clearances ... which camp?

Post by fasterdammit »

Hey Finn

Yeah, it's definitely a cold engine. She hasn't been fired in about 2.5 years (which explain my absence from this forum). So I didn't get the high revs in, but believe me - the valve chambers are pretty clear. ;)

I've done valves on my Monster (a couple years ago, now) , so I'm not unfamiliar with the process - but considering my measurements were only marginally out of spec, and the the sort of vague opinions around the internet, I just thought I'd ask the question here anyway.

I had a length of solder attached to a 5mmx20 screw which I dropped into the oil return holes, but I think I like the ear plug idea better. The solder was handy because it was long enough to get looped over the side - so you couldn't put the valve cover back w/o first removing it. I don't think I'm likely to forget a brightly-colored ear plug though, and that would seal the hole much nicer. Good call.

And makes sense to adjust both, yeah ...

@McTool: that describes my closers pretty well. I can turn the closing shims when I load the closing arm. And the loaded gap on the opener is marginally higher than the unloaded gap, which confirms it. Guy Martin recommended to me the same thing w/ the closers, upon a discussion of the Monster (I bought his collet kit for the Monster; may do the same w/ the Paso, we'll see).

Thanks all. :thumbup: Cheerio!
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Re: Acceptable valve clearances ... which camp?

Post by Mc tool »

The ear plugs are a good idea , I plug the holes with a bit of grease , but yeah ' a bright coloured earplug would be hard to miss, and if your of a " thrifty " nature you could still use it as an earplug, certainly would slide in easily :lol:
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Re: Acceptable valve clearances ... which camp?

Post by Finnpaso »

Hi guys!

That "earplug" is old "trick", what was one of first ones i learned from local guys here who have played very long time with Ducati engines, when they showed to me first times how to adjust Ducati valves... :mrgreen: Its little funny, that i put allways papernote before valve adjusting to fuel tank where reads: "Muista sitten ottaa korvatulpat pois!" = "Remember then to take ear plugs away" :) I have never forget ear plugs to oil channels and never dropped anything to inside engine, but i have heard one case from Finland, that such "used"(and very hard!) earplug have been found from that area just close that coarse oil filter(without any harm to engine), so remember to take them away after all is done before put valve covers on... :thumbup: :thumbup: :thumbup:
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Re: Acceptable valve clearances ... which camp?

Post by Desmo_Demon »

With my 2V Ducati engines, I shoot for 0.004"-0.006" (0.10mm-0.15mm) for the openers and 0.000"-0.002" (0.00mm-0.05mm) for the closers. I've heard of the clearances that you mention, but I just what I listed (I think I did my metric conversion correctly).
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Re: Acceptable valve clearances ... which camp?

Post by fasterdammit »

Desmo_Demon wrote:With my 2V Ducati engines, I shoot for 0.004"-0.006" (0.10mm-0.15mm) for the openers and 0.000"-0.002" (0.00mm-0.05mm) for the closers. I've heard of the clearances that you mention, but I just what I listed (I think I did my metric conversion correctly).
I spoke w/ my buddy Steve @ ECS about the clearances as well, and it seems like .006" is still tolerable, so I think I'm just going to wet-sand a tinsy bit off the .003" opener shim, and then let it all ride until the next check. At which point I'm planning to put MPB's collets in there, so things may change then anyway.
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