What the difference bewteen the 1985 atc250r motors and the 1988-89 trx250r motors? Which is better??

 

I'm not really familiar with the differences between the ATC 250r engine and the 88-89 250r engines, but there is a web site that will be able to help you.

The web site is www.webspan.net/~rpfirley/atv.htm

This web site has the specifications of all the older high performance bikes and discusses the differences between engines.

So check it out!