[paul]

I bought a hacked on sled. Someone has micky moused this thing real bad. The problem is I think the carb on it is to small. It is a single carb, 500 air twin. Its got I believe, a 32 Mikuni with 240 main jet and 35 primary. When I first got it, it over heated from only running on one cylinder and seized. Its got a brand new rebuild. So its not the engine or ignition system, been there, done that. It keeps fouling the fan side cylinder. I put an old ski doo carb on it with the 240 main and the 35 primary jet with no problems in flooding fan side cyl. I believe it is a bigger bore carb. except that carb has no choke on it which makes it a ##### to start.
So question is,
1. is there any way other than measuring the throttle bore to tell what size carb it is?
2. What MM carb size should it have? 36, 38?
I think that the carb is to small and sucking to much gas making it foul. make any sense? thanks.

 

[Auggie]

Well, in 1980 the 500cc fan cooled Panther and Pantera used a weird Mikuni carb. The Panther used the B40-34-1 (34mm) and the Pantera used the B40-36-1 (36mm) carb. The specs for the Panther 34mm carb is as followes:
Main jet = 290
Pilot jet = 95
Pilot screw = 1/2 to 1 turns out.
The Pantera specs are as follows:
Main jet = 300
Pilot jet = 105
Pilot screw = 1/2 to 1 turns out. If you need anymore help let me know.

   -Auggie-

 

[paul]

B40-36-1 what does the B40 mean, and what does the 1 mean? How can you tell a Mikuni carb type? is there any book out there that will tell you by numbers/letters stamped in the throttle slide?

 

[Auggie]

Well, all I can tell you Paul is that a regular Mikuni carb (VM style) has a round slide and a square float bowl. The B40 carb has a butterfly throttle plate and a round float bowl.

   -Auggie-