I do my routine maintenance and use the MOBIL 1 V-Twin 20W50 in both the engine and primary. During a conversation the other day with the local HD service manager he recommended I run non synthetic in the primary. His basis was a local guy who dynos bikes has noted clutch slippage on V-Twins with synthetic in the primary.

Any others recommending this? I change out my primary and engine oil every 2,500 miles and haven't noticed any slippage, but my scoot hasn't been dyno'd.

Edmo

 

I have heard about the slippage problem from other people. I talked to a custom builder in town about that, he said he uses synth. in the primary all the time. He said usually the problem is the primary being over full and the clutch is in a bath of oil.

 

I just had HD do my 1,000 mile service. They put synthetic in both the engine and primary. and 75/90 oil in the tranny.

 

I run Full Synthetic (Amsoil) in all three hole's. 98HP & 104TQ with with over 15,000 miles on the stock clutch and it still pulls hard, with no clutch slippage. I change mine every 5000 miles. But everyone will have their own opinion. Like 85eglide stated don't over fill.

 

I agree. This problem with clutch slippage is an old one and has been resolved several years ago. Amsoil has proven this over and over again. I'm sure if this is still a problem, Harley wouldn't come out with the Syn3 oil either.

I have used Amsoil in all three holes for over five years and never had any clutch problems.

 

I like HD's Formula+ - have noted zero clutch slippege / wear. Have 15 K on the bike.

 

That is not true of Mobil1 big twin or the amsoil Mv for harleys, it has a agent to prevent clutch slippage and it tells about it on the websites and the bottles too, but some synthetics dont and they will cause it in high torque bikes

 

HD Formula+ in the primary, Redline Shockproof Heavy in the Tranny and HD 360 20W/50 in the engine.

 

I have been using Royal Purple MAX-Cycle 20W50 in all three holes for 5700 miles now with no clutch slippage or any other problems.

 

I use Mobile 1 V Twin in all three holes. Have 30K on my 2000 Ultra with the original clutch and not one problem to date.