VF500 - 1986 vs 1984 Carbs

My 1984 VF500 has 1986 carbs on it, as well as several other 1986 parts. The bike has an interesting history and has parts from at least four different bikes now that I am done rebuilding it. I left the 1986 carbs on it because I knew that the bike was running with them when I tore it down to fix a dropped valve and to do a frame up rebuild.

Now that it is running I am considering cleaning up and installing my 84/85 carbs. I have two of these and one is really clean with the chrome still un-pitted on the float covers. The linkages and everything about them are superclean.

Questions:

- Aside from the cosmetic, what kind of performance gain should I expect? I know from my MX days that the larger carbs should result in improved top-end and reduced bottom end. Will I really lose that much on the bottom? How might the midrange be impacted.

- I would like to get the jetting fairly close on the first attempt. The bike has a K&N filter and a bastardized Hindle 4-1. Any suggestions on main jet selection, needle shims, etc?

 

I ordered new carb boots which should be in about soon and then I am doing the carb swap.

Any suggestions on main and slow jet size to use with the older carbs? Should I stick with the 95 main, stock needle and the 38 slow jets? What are you using with your 84-85 500's?

BTW - there are 95 main jets in the smaller 1986 carbs on the bike now. Spark plugs show a grey / tan burn. The bike is running hot and I am wondering if I may be a bit lean. However, the previous owner who kept put the 86 carbs on the bike used the larger carb boots. As a result, the clamps are tightened all the way onto the smaller carbs and I am wondering if there is a good enough seal there which could lead to a lean condition.