Friday (late sunday now) i changed the oil in my 99 KQ 300 and i am having some issues with the "oil temp" light.
After i changed the oil, me and a friend went on a pretty good ride, alot of low gear high RPM hill climbing, and my oil temp light cam on, so i let her sit for a while. After what seemed like forever, the light still wouldnt shut off while running. So we just headed home and on a good long stretch (about 2 miles, i can keep it in fith topped out the whole way) the light went out and stayed out the whole rest of the way home.
Today i went to start it after i washed it and the dam light came on instantly, and it seemed way underpowered. I kept ridin it for about 3 mins and the light went out and the power seemed to come back. I used Rotella 15W-40, and have been using it in similar quads as have friends with no issues.
I can only think im having an issue with the filter, but wanted to get some unbiased opinions also.

 

wow, i have the EXACT same problem, and word for word this is what happened to me too.