Ok, I have a 1989 Trailboss 250 2x4 that is near and dear to me as it was my first ATV. Lately, it is occasionally making a horrible grinding noise when taking off from start at full throttle.

The engine appears to be running fine. Acceleration is slow until after the grinding stops, but other than that the vehicle runs just fine.

The noise sounds similiar to someone running a large stick down corragated tin. I could record the noise if it would be helpful. I can recreate the noise by having someone stand behind the bike, hold the racks, and take off at full throttle (this is only a 250, remember). The noise sounds like it may be coming from almost directly below the driver.

Any suggestions? Chain? Sprockets? Drive belt? Something worse? Note, the bike has not gotten wet. This can happen out in a hay field.

Someone please share some expertise.

Thanks in advance!

 

IT sounds like your front sprocket. Thats the sound my trailboss made when the front sprocket went bad. It made the noise one time during a ride. I didn't know what it was either at first. Then it kept getting worse until most of the teeth were gone. I was lucky to make it back to the truck. The new sprocket was about $15.

 

He is right check the sprokets first then check the chain tention.I had a bad trans in my 95 Trail blazer where the chain inside the tras was streached or something but luckyly for me they replaced it. If it is the sproket there is one thing I would invest in for it an that is a chain tensioner for it from HPD.