I guess I'm using the wrong oil? clutch slippage

Well, I got my bike sorted out (see my other post) and once I got the idle and stuff all set up, the bike runs great, probably better than it did before.

I noticed that in fourth and fifth gear, I can hardly give it any throttle or the clutch slips. It did not slip before, and I did change the oil while I was going everything else.

Just looked at the other "clutch slipping" thread, I used Havoline 10W-40, which I guess is the wrong stuff as I'm sure it has no friction modifiers in it.

Is there any other auto parts store oil I can use, or some sort of friction modifier I can add? (I'm guessing the additive for clutch-type limited slips won't work?) Or, am I gonna have to go to the local motorcycle shop and fork out big bucks for "motorcycle oil?"

I believe what you want is oil without friction modifiers. Nowadays it seems like they're doing something weird with all the new oils, i.e. Energy Conserving. I just found at Pepboys, Castrol 4T "for motorcycles" at $4 a quart. It is SG, SH rated instead of the SL, SM rating all the regular stuff on the shelf has.

I haven't changed it though so no reviews yet.

The oil isn't causing it. What is I haven't a clue though.

The oil ISN'T causing it? :huh:

Crap, are you sayin' that all "straight" oil is gonna have friction modifiers? I've just been usin whatever straight oil (20/40) is on sale. I haven't changed oil since last fall.

Any of the multi-weight diesel oils will work well in our bikes. I've been using the shell rotella 15w40. I usually get it at Sams Club for around $30 for 3 gallons. You can also get it at Walmart.

ghunt81 - Your clutch slippage is probably due to worn out/tired clutch springs. Have you tried to adjust the freeplay in the cable? When was the last time the clutch was serviced? I recently replaced the fiber plates and springs on my bike, what a world of difference. Before I could barely get the bike to go over 50mph. The engine would rev up but the bike would not move. After the parts replacement the bikes runs great.

ronjones wrote:

Crap, are you sayin' that all "straight" oil is gonna have friction modifiers? I've just been usin whatever straight oil (20/40) is on sale. I haven't changed oil since last fall.

The oils that have the friction modifiers are the ones with the starburst symbol on the bottle. These would be 5-20, 5-30, etc. Oils in the 30, 10-40, 20-50 range do not have this symbol and are fine for our bikes. I live in SoCal where the weather ranges from maybe 40 up to 100+ so I use 20-50 with great results.

Well, last night I adjusted the clutch again after i got home. I guess I must have had it adjusted wrong because I rode it in to work this morning, I was cranking on it pretty good in fourth gear uphill and it didn't slip, and then tried fifth on a flat surface and it didn't seem to be slipping either.

Guess I'll see what happens, if nothing else I suppose a clutch job could be a winter project.