Wanted to know if i should go with the hp4 or the gn4 oil and what kind of plug should i use the std or a iridium plug.

 

If you change your oil regularly the GN4 will serve you just fine for the life of the bike. There is really no need for a syn oil in an atv as often as the oil should be changed. Syn oil is meant to extend oil changes in a vehicle, and you shouldnt extend the oil changes on an ATV. The big enemy of an ATV is dirt, not oil wear, so nothing is really gained by using syn oil other then spending more of your hard earned money.
As far as the Spark Plug goes, Using the stock type and brand will give top performance for the ATV.

 

I run the irridium plug. Subjectively, I would say that it makes it a little more snappy off the bottom end.

HP4 is a petroleum/synthetic blend. The synthetics have wonderful properties that make them far superior to a just plain old petroleum oil like GN4. It is worth spending the extra couple dollars to run HP4!

You do want to avoid HP4M, which contains moly and can make your clutch slip.

 

Some good oil info: http://forums.atvconnection.co...id/21/threadid/520475


My personal preference is Maxima oils. They have the best additive package in the industry. They have Premium which is a budget petroleum oil, Blend which is a petroleum/ester synthetic blend, and Extra which is an ester based 100% synthetic. I have been running Extra for over a dozen years....my engines last forever and a day!