Regular versus synthetic lubricant

[yeehaw1960]

I talked to a guy who was about in tears in the local O'Reily auto parts last Saturday. He said he put synthetic lubricant in his bike after draining the regular oil from it. Now his clutch is slipping at high RPM. I've heard that changing things up after a few thousand miles is bad news for some bike's clutches. Can anyone educate me on this? I told him to find out what was in the crankcase before he changed it, find some of it, change back, run to operating temperature and change it again using what originally came out of it. I wouldn't have volunteered anything if he didn't sound so desperate. Am I full of cr*p?

 

[tropic]

I think your advice was pretty good considering you made it up on the spot. Sounds like he used a lube with friction modifiers that don't play nicely with wet clutches. If he dumps the lube for a more suitable one, puts some miles on it, and dumps it again I think he'll be better off. I can't imagine any additive holding up to plate on plate contact if it isn't constantly replenished with more from the sump oil. I hope he didn't overheat the clutch too much when it was slipping, though.

 

[PT1]

I use redline synthetic MTL & MT90 50/50 in my wet cluch wth no issues. Both contain no moly. If he put automotive syn oil in that could be it. If your friend has a shared sump and wants a good 90wt try redline MT90.

 

[kballowe]

Yeah - I don't know ...... could be possible that he already had this problem and didn't realize it until someone told him that synthetic oil would make his clutch slip.

Just sayin'.

We have guys in our group that 'get away with' a lot of "Energy Conserving" automotive oils in their bikes. I personally ran Mobil 1 5w-30 "energy Conserving" in a Gold Wing for 15,xxx miles. Two-up and pulling a trailer and no clutch slippage.

But back to the original question - YES you gave him good advice. If it slips after that, then it wasn't the oil.

My personal opinion, you understand.

 

[FZ1]

It's the oil. Just drain and fill with some mc specific oil,run it and drain it and repeat if necessary. Some bikes don't make enough power to slip the clutch.

 

[dnewton3]

Regarding the specific issue of the guy in the parts store, we know little of the actual scenario. Was the "synthetic" EC or not? What vis? Was it even a wet-clutch bike? How has the bike been maintained and treated? Too many variables to make a specific determination for the guy nearly in tears.

The term "synthetic" is about as ambiguous as it can get. It implies little other than group III, IV or V base stock, and speaks nothing to the additives.

If one suspects oil is the culprit, change it and see if the problem continues or disappears, then work from there. Yeehaw1960, your advice was good, given what you've told us.

 

[TucsonDon]

Originally Posted By: kballowe
I personally ran Mobil 1 5w-30 "energy Conserving" in a Gold Wing for 15,xxx miles. Two-up and pulling a trailer and no clutch slippage.

Hard core, man ... hard core.

 

[Norm Olt]

I guarantee that a bike with 80-100 lbs./ft. will be more sensitive to clutch slippage than one with 20, all things being equal. Low $ide I'd consider a 20W-50 semi-synthetic like MaxLife (as in "$0.99 after rebate") and on the high $ide Amsoil AME 15W-40.

Just IMHO.

Cheers!

 

[Mackelroy]

It would depend on how stout the clutch is, the goldwings where slated to run Honda Moly fortified oil.

My VFR manual says avoid like the plaque

I dont know enough about EC oils, being anything other than lighter weights and less extreme pressure additives.

However the Redline Mc oils that I've seen are MB rated fluids and have tripple level of moly supply of most oils. Does not meet MA friction properties

If you dont have a very stout clutch, it might show you why you should run something else in the wet clutch.

 

[Norm Olt]

There are two kinds of moly and you need to do a little searching on a couple of the other boards (passenger car & oil analysis) to get the distinction right.

Cheers!