Curtis, I'm afraid some of your facts are whack..
The 85/86/87 250ES all had exactly the same engine..there were no changes made to account for your claim the 86 had 'way more power'. All three years have the exact same torque, HP and gear ratios..
The only explaination for your feeling that the 86 was more powerful is that any 85 you must have engine or carb issues..
Also, there was never a rev limiter on the 250ES..
The improvement applied to the 86 model were minor engineering changes such as improved rear brake design to keep water out, improved cam tensioner design, addition of a helmet holder..etc. No major updates like the changes from the 84 to the 85 250r as you suggest.
Current toys..
1986 Honda 350X..trail bomb!
1985 Honda 250SX..my main mudder
1985 Honda 250ES..Back in Black Trike
Current non-trike toys:
1990 Honda TRX300FW
1995 Seadoo GTX
1998 Polaris Indy Lite 340(Nearly new looking)
1998 Polaris Touring 500
1998 Club Car (electric)