I am about to make my first oil change on my '91 Yamaha Big Bear 350 4x4. I bought it used about 6 months ago so this will be my first oil change. This machine does not seem to have an oil filter.

I have asked around locally and am getting conflicting information from different people. There are ones that have used regular oil and all is well ('91 HONDA 350 4x4) while others advocate strongly to use ONLY oil made for the ATV ('98 Polaris & '97 Arctic Cat). The manual calls for Yamaha's brand of oil. What the hell is the difference in using a good 10w40 motor oil or theirs, which costs a lot more. It is still 10w40. I read a discussion about reducing the heat from ATV engines. The topic called for using Castrol 5w50 Synthetic. This will significantly lower the heat from the machine. HELP !!!!!

Anyone have any usable and sensible advice.

 

I have a 2000 Wolverine and I run Mobil 1 5w30, I was told by someone on here to use 5w50 but I couldn't find any so I got the 5w30 until I find the other

 

As far as oil goes, you should buy one that is designated as a motorcycle oil. Castrol make one for sore and it comes in 10w40 and 20w50. It is more expensive but it is designed for a wet clutch motor . If you use an automotive oil in it you could burn the clutch out of it because of different additives. You could also use a synthetic oil but when you use it in an older engine you will usually get some small oil leaks that you didnt have before. This is because the oil is so thin . Also with synthetic in an older engine you may burn some too because it can creep by the old rings.But synthetic is nice because an air cooled engine will run cooler.

 

I've used Penzoil 10w40 in every quad I've owned. From an 87 suzuki lt230 to the warrior I have now, with no ill effects. Run what you want.

 

as long as the oil is 4-cycle oil with se,sf,or sg api classification you can use it,just use the right viscosity.the only difference between automotive oil and atv oil is the price.i usually use castrol 10-40 for the first oil change then i use amsoil 10-40 synthetic and synthetic gear oil in the rears afterwards.mobil 1 is also a good synthetic

 

WTAVCAR,

As you have seen, you have asked a question which will invoke a great deal of personal passion. Which motor oil to use is analygous to asking, "What church should I attend? or, Who should I vote for?"

Because many ATVs use the same motor oil to lubricate the engine and transmission, the potential for oil shearing is there. Oils should be changed frequently in an ATV to eliminate this and other wear factors.

An oil with additional anti-wear additives would be recommended, such as one that contains zinc.

Motor oil labeled SJ is not necessarily the most engine friendly even though it is the latest classification. Go to a local motorcycle shop and read the API classifications on the Yamalube, Honda GNC etc. and make your own decision.

Changing it often, is the best advice.