Walmart supertec 10 bucks a gallon
Quicksilver at walmart 25-30 a gallon
Yamalube 30-40 depending on dealer
Synthetics??? 40-60+
Different ratios of mix for everyone so lets say abouts 40:1? Thats 8 tanks in a stock sj. A tank prob last 1-4 hrs, depending on rider. 8-32 hrs of riding per gallon of mix. Most 701s prob see 2-400+ hrs of use before something bites the dust. Around 20 gallons of mix per engine is what it boils down to for most people. A Pro x topend kit with gaskets is 200 bucks, and its 25 bucks a hole to bore cylinders.
If you do the math its more cost efficient to buy cheap oil, for me anyways, unless some reason the "good" oil gives more power. Theres a whole bunch of oil debates on here. I dont have a super pumped up engine, but I DO put more hours on my ski than anyone I know, and still have yet to have a oil failure. A built 900cc dasa engine with some crazy pipe and porting will prob want synthetic, but I wouldnt bat an eye at any oil myself.
On a side note, again I bring it up, Walmart supertec is EXTREMELY similar to Yamalube. They smell the same, look the same, burn the same out the pipe, and everyone at our dealer thinks they are the same thing. There are only so many oil manufacturers. Just my opinion on the subject.