Oil question about oil changing

[bueller]

Hi there,
New to forum, just gonna throw this out there....

I've seen several people post about oil changes, and using automotive oils.  Back when I owned my 78 750k, a friend of mine had a GS1100.  We put automotive grade oil (rated SJ) in his bike and the clutch started slipping shortly thereafter.  Now we were talking to some people about it and they had informed us that because the clutch rides in the motor oil, that the current oils were too slick and would make the clutch slip.  To confirm this, we put some motorcycle specific oil in it and the clutch slippage was minimal after that.

So I guess my question is, are you all seeing any problems like that, or have they changed the oil ratings again (its been a while.....) to where its ok to run them?

The information makes sense in my head, and I've seen what happens first hand.  Just be careful what you put in your ride ;)

Frank

[Rod_Knockin]

I run royal purple synthetic 15 w 40 with no issues. I got this response from the RP tech department

Matt,
 
The RP 15W40 will work fine in a wet clutch assuming that the motorcycle clutch was set up to use a multiweight SAE 40 wt oil.
Being a synthetic has nothing to do with it in the case of RP oils.
 
If the 750 was set up to run on an SAE 30 Wt - using a heavier oil might make the clutch slip due to the thicker oil film.  This would only be aggravated by using a synthetic due to the flatter viscosity curve of the oils.
 
Conversely, using a lighter oil might make the clutch grab if set up for a thicker oil.
 
You should be fine with the RP 15W40 or any of our other products in the correct viscosity grade for the application as we do not use solids or excessive amounts of polymers which can have an adverse clutch operation.
 
David
 
Royal Purple Inc
David Canitz
1 Royal Purple Lane
Porter, TX  77365
281.354.8600
281.354.7600 fax
713.725,7207 cell
[e-mail]

[woodsrider250-2]

If you run regular motor oil make sure it doesn't say 'energy conserving' on the back.  These are the friction modifiers that will trash a cork clutch disc.  Best bang for the buck is Rotella Synthetic in the gallon jug.  I've run this stuff in all kinds of wet clutch applications for years.