Farmr123,sorry to hear about those those seized up cams.I have never had any trouble with a OHC and I've done just about everything you can do with a quad. Maybe the pushrod design keeps the cam cooler than I think,it would look like on a watercooled engine the difference wouldn't be that great.Walexa posted that some people think the Prairie has technological advances that the 700 is lacking, but the Prairie's V-Twin engine isn't high tech,V-Twins has been around for a long time,just not on quads.Look at the Banshee when it came out 15yrs ago and people said "uh,ah,wow" just because of the twin engine,that engine was taken straight off of Yamaha's RZ350 street bike, not a high tech quad,just a street bike engine in a quad. Without Polaris we probaly even wouldn't have auto trannys,thats the biggest thing that has changed quads over the years,the push rod engine problay won't be as catching as the belt drive idea.The 700 does put out about 4 to 5 more HP,but it also has 50cc more than the Prairie 650. So pushrods or OHC keep riding,I'm in it for the fun!!

 

Trailhog, you maybe right, water cooling would probably make the difference in keeping things cool. I was just pointing out that in some engines, the heat can go 'up' into the cam area. I suppose a pushrod engine would get the rockers pretty hot, but I don't think they are as stressed as a cam is.
If you want to overheat an engine (air-cooled) ride double on it, idling through some brush thickets on a hot, still day, pulling/hauling a sprayer, putt-putting in low, spraying the brush. Believe it or not, that will overheat the engine quicker than running it wide open (at least then there is more airflow).
I still think that if the dealer would have sold me the machine with the 'extra' oil cooler, I would have been all right, but he didn't have one on hand, and I think was too concerned with making the sale than seeing I got the machine that best suited my needs.