What additives in oil are bad for wet clutches?

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I know you should run JASO spec oil because of not wanting friction modifiers that can mess with the clutches. However looking at UOA's confuse me because these cycle oils almost all have things like moly and boron in them. Of course they also have the normal zddp. So what additives are supposed to be a problem?
 
I'll let others discuss moly, but I'm guessing Tungsten wouldn't be advisable, however it is used only in one oil that I know of: Liqui Moly Molygen
 
I think it's high amount of molybdenum that is the problem. Having some moly is ok, but globs I'd be hesitant about using.

But Im sure someone way more knowledgeable than I will give better detail or correct me :]
 
From everything I have read just never use any oil that has the "Energy Conserving" on label. I have used Rotella and mobil1 car oils in bikes, Quads and dirtbikes's for years without a single wet clutch issue. Current sportbike makes 200+ HP ...and no clutch issues.
 
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Years ago Liqui Moly had small 75ml cans for small engines and motorcycles. This is what they say about it.

Quote:
For motorcycles with wet clutches, add maximum 2% of the oil filling volume.


In 4qts oil 75ml (2.5oz) is the max. With wet clutches you are better off with no additional moly IMO.
 
Anti-wear and extreme pressure additives are typically ok; friction modifiers are not. MoDTC at too high a concentration will cause slippage, but small amounts might be ok (depends on the rest of the formulation). Other types aren't going to show up on an oil analysis such as organic friction modifiers, or might be hard to pick out of an elemental analysis such as phosphorus and sulfur based additives.
 
Somebody forgot to tell Redline oil users they are having issues with the wet clutch. Me too, the Delo is just making it slip left and right. Not.

I'm sure there is truth to that, but at 400+ ppm moly isn't enough. I always thought it was FMs that did not show up in the UOA, something non metallic.
 
The only problem I've had with moly was back in the '70's when I built a Triumph using moly assembly paste. Triumph's don't have a wet clutch, it's just a bit damp. In later models the left side oil seal was removed and they used the chaincase as a breather chamber...so some of my engine oil got in the chaincase. The clutch would slip for 5 miles until it gone hot, then never gave any problems.
 
here we go yet again on all of the total mis-information about moly

i have tested dozens upon dozens of oils (its over 80 now) and the highest MOLYBDENUM was 135
with 20 samples being over 50 with ZERO (that is NO) issues with the clutch.

if you have clutch problems its the clutch, not the oil
 
Originally Posted By: sunruh
here we go yet again on all of the total mis-information about moly

i have tested dozens upon dozens of oils (its over 80 now) and the highest MOLYBDENUM was 135
with 20 samples being over 50 with ZERO (that is NO) issues with the clutch.

if you have clutch problems its the clutch, not the oil

That's pretty much the gist of what everyone else has responded with. There hasn't been much of any "misinformation" shared here.
 
Or you have weak clutch springs like my C90 Suzuki and my 1100 Honda. Replaced the clutch springs and no more slipping. Wish I could find the pic's I had of the difference between the stock and after market springs.

ROD
 
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