It was stock.Just bored.Pipe and add ons.No port work done or anything like that..After 19 years old it was on it second bore,when i bought the quad.That was a guess on hours.I rode 6 to 20 hours a week.More then some .I do ride alot.100 hours seem really short life to me.I say all ported up thats probally right.But with stock ports its just getting warmed up. When i first got it.Also the only reason it went down the first 2 times.Was because the person i bought it from didnt put any thrust washer in the upper pin.After the second topend.I called Wiseco and they said i didnt need thrust washer with thier piston i was using.which the person i had bore it didnt know..Well they were really wrong..Well right at a year it beat the piston  up pretty bad It knocked the pins out of the piston were the ring seat over to keep them into place.  .Now i got rm bearing and billet thrust washers..Well in that rebuild i took the cases apart and put new crank bearings in and a crank.Well the oil plug was stripped.And when i put a helicoil in i got the shavings from the case in the motor.I spent alot of days cleaning it in a part washer.Which did work well because a year of riding with no issues.I do thankyou for your help.;I did find the problem last night.I done what you said with the chain off.The motor is tight.For some reason the bearing are rough in the carrier.So im glad i did listen to you and not get into my own way and take it apart to see nothing was wrong with it.The motor went threw all the gear didnt have a sound or a problem or a jump or a thump at all.Smooth as could be.So im going to work on the carrier here in alittle bit to fix the problem i think it is the spacer is too long and blinding them up.But thanks for your help and anyone who posted with idea to help.Il be back later to post my results.