ok, not to get in the middle of this, but i found a website saying that molyebdum is the additive in most auto oils that causes wet clutch problems. If you look on the back of automotive oils you will see a donut shaped drawing. On the bottom portion of the donut it will either say nothing or energy conserving. Oils with high levels of molyebdum(bad for wet clutch) will say energy conserving. They help gas mileage but sacrifice engine life and wet clutch protection. I cheched out the local auto shop and found a few brands of auto oil without the energy conserving mark. I would assume these oils would be VERY similar to atv/motorcycle oils. And it was also a synthetic.

your rebutle ----spelling?

 

i think putting oil for a car in in a atv or street bike is a bad idea for a few reasons

1) atvs and motors run at much higher rpms cars run max of about 5-7x1000 atvs 8.5-10x1000 bikes 12-15x1000

2) atvs run hot mostly air cooled like my 300ex because of the highier rpms

3) motor,trans,and cluch is in the same oil. never seen a car with a setup like that

 

Ok guys thanks for the input, however after reading articles wrote by engineers and physics majors, they all had good points as to Automotive oils compared to motorcycle oils. The ideal oil--Good brand (mobil 1) Correct weight for tempurature application (15w-50) Fully Synthetic, Contains no Molyebdum friction modifiers. Decent price 23.00 for 5 quarts. Also, i will be changing oil FREQUENTLY ( 20 hours) with a stainless steel reusable CRT oil Filter.

 

I have used castrol full synthetic in my Eiger since new and it had 700 mi with no clutch slippage or failures so far.

 

Old thread, but I'll throw in my 2 cents...

I wouldn't use regular auto oil unless I absolutely had to in order to get out of the woods or something. At this moment, I'm in the middle of taking my clutch out and cleaning all the Castrol 20W-50 I put in there because I thought it would leak out slower instead of fixing the leak in the first place. Dumb.... My clutch was working fine before, now its driving like a high-stall torque convertor and doesn't fully engage until the engine is almost revved out. I tried flushing the engine with kerosene, but it didn't clean the oil off the clutch, so now I have to take it apart and manually clean the clutch surface. I'll never use regular oil again... Especially the really slick Castrol GTX stuff.

Lately, except for the Castrol episode, I've been using the cheap "Pre-1988" oil from walmart. Its very clean and clear looking... Kinda resembles a thin mineral oil. Its been about a year now and all my clutches are fine and the engine parts I've seen don't look any different than they did with any other oil. The only sludge I've seen is clutch particles n whatnot. You can't beat the price of the oil though... $1.24 a qt! I change it when it looks dirty and the total cost is about $6.00.

 

I change the castrol syntec (Fully Synthetic 5W-30) about every 200 miles of service give or take a few miles with 0 failure or clutch slippage. I do not use the fully synthetic in my CR-250. I use the regular Castrol GTX 10-40 and change it every three rides with no failure. Could be because of the frequent changes I don't know but I am very hard on the clutches in corners and climbing very large hills. What I'm saying is I find it hard to believe that this oil is bad for my machines after several years of abuse on both machines without replacing the disc,springs or plates. I have inspected both clutches regularly and have found no faults as of yet. " If it ain't broke don't fix it"!

 

I was talking about the centrifugal clutch in an auto-clutch quad... I failed to point that out, oops. The manual clutches isn't that noticeable. I ran Castrol GTX in my 750 Honda for years without trouble too.

 

A would ask a few questions before making a recommendation, most of which have been asked.
But these ones are the most important... how long do you want to keep the machine? How much do you care about the machine? Do you enjoy the performance you currently have? Can you afford replacing your main bearings, clutch plates etc. Can you really only afford cheap oil and filters? If you answer those questions the answer will become clear.