I'm currently re-buiding/restoring a 86 250r! Anybody know why it's faster than the 85? I thought they were identical except for few cosmetic changes (engine color etc)??

 

There are a few differences between the 85 and 86. One big thing is the carb. The 86 has a PJ carb, which is a better carb than the 85's PE. Plus if you read through a Clymer manual, you'll find a bunch of tiny differences.