Hi, my son has an 87 250x fourtrax. LAst winter rebuild all suspension, bearings, bushings, tie rods, just about everything. New tires, graphics, handguards, etc. Motor was running great so just added new Big Gun Exhaust and jet kit and filter and let him run like he had a new quad. Now being an 87 and all, it is blowing alot of smoke out exhaust. Burns quite a bit. Was wondering about putting in a Hot cam and Wiseco Pson and ring kit and getting him back on it. Without doing alot of machine work what would you recommend doing to this while I've got it apart. What compression piston or cam or just any info any one may have to do to this while we have it apart. Like I said it runs great, just burns the oil. Thanks Don

 

Sounds like you should also look into a valve job while its apart, probably need seals on the valve stems if it burns oil. Pay the extra money for a good porting job and look into a "big valve" kit, the head is a major flow bottleneck on the 250x/300ex. Open that up, and you will really see some performance increase with the pipe and a new cam.

 

I'd steer clear of Hot Cams. Check out Megacycle, they're highly recommended. Webcams would be a fair second choice. New springs are the most important thing to do however.... Even if you stay with the stock cam.

Get a wiseco piston.

Before doing any porting, be sure to spend some time reading this: http://mototuneusa.com/thanx.htm