Having only had 110's and 125m's and a 81 250r i don't have any idea what this is. Its on my 1986 YTM 225DR Tri-Moto. through this site i learned how to jet the carb on this, runs like a dream now, and also how to fix the reverse, also works now. I haven't messed with this lever as i don't know for sure what it is. Can someone clue me in?
I would say looks like some kind of compression release. I don't know much on the 225s though. Alot of hondas had compression releases. Most were cable activated with the pull starters or kick starters, the earliest was manually set with your hand.