i like royal purple max cycle 20-50.....its cool because it really is purple..........amsoil is good stuff too the royal purple is just more readily avaliable around here......i have also tried maxima4, synthetic honda, spectro synthetic, kawiechem and a few others.....the maxima is good for a non synthetic and works great for break in's,synthetic honda is decent but not worth the 9.99 per quart but still dosnt compare to amsoil or royal purple, spectro is complete junk and gets dirty real fast and the kawiechem is also ok for a non synthetic......for a break in or if your looking to save money run maxima 4 but if you want a good synthetic royal purple or amsoil would both be good choices

 

I use Amzoil 10w 40 in my praire and all of my air cooled motors, including my lawn mower 20 hp v-twin Koehler, wifes bear tracker, son's 400 ex, been using it for years, have never had an engine problem. Also use Amzoil diff fluid in both wheelers and lower unit on my boat motor.

KenR

 

Redline synthetic 10w-40 motor and front diff......

 

Everyone is going to have their favorite oils. Just like everyone has their favorite quad....opinions are like a$$holes everybodys got one. I used to run regular 10 w40 car oil in my 94 fourtrax, and look at it, 7000+ miles and still kickin. In fact it starts better than my brute.[img]i/expressions/face-icon-small-wink.gif[/img]

 

Right now I have Mobil's synthetic 10-W-30 in my quad, but I plan to switch to their synthetic motorcycle oil next oil change for the wet clutch protection? By the way I have a Q to add on how often do you all change your oil filter?

 

The only real reason I use Mobil 1 is it is available at the local "AutoZone".
Been using the Mobil 1 M/C oil since my '02 P650, great stuff.

 

I change my filter every oil change. (200 miles) It's better to be safe than sorry. Which would you chose 16 doller oil filter, or 1500 doller rebuild? It may just be me but I run my wheeler very hard, and I edge to the cautious side when it comes to oils.

 

Mobil 1 15-50
Mobil 1 10-40 SUV (almost identical to M/C formula)

 

does the 10-40 have wet clutch protection? just wondering.

 

The car oils you need to watch for are oils that state energy conserving in the API label, or oils that have friction modifiers such as high levels of molybedenum, graphite or lZDDP. In general auto oils focused toward diesel trucks are chemically very similar to M/C oils. I live in Phoenix so I prefer the heavier weight oils for a little added protection against the Southwestern heat. I have been running the full synthetic Mobil 1 15-50 and 10-40 and am happy.