Carburetor body worn

[Mailman]

I haven't started my bike yet so I'm unsure how much of a problem this will present. My left side BS38 carburetor has some wear internally where the butterfly valve , under pressure from springs on the butterfly shaft , have caused the butterfly to wear into the carb body. To remedy this , the PO fabricated a really nifty shim made from a beer can then he wired it in place and covered the whole mess with a big blob of unknown substance.

These pics were taken prior to dis assembly and cleaning. I'm sorry I never took any good pics of the wear inside the carb body.
I replaced the novel beer can shim and black goo with a shim I made from filing down a washer until it was very thin. This did a good job of pulling the butterfly back to center and everything works smooth. I just don't know if it will leak air and if that will be problematic. Here is another pic inside and if you look along the edge of the body you can just barely see the damage.

Sorry I didn't take any pics after the repair.
So do you think this will come back to bite me? I'd hate to think my carb body is ruined.

 

[weekendrider]

Did you replace the throttle shaft seals during all this?

 

[Mailman]

Yes, all new gaskets and seals. Throttle shaft seals included.

 

[5twins]

After the return spring and various lever bits are installed on the left side of each carb, the spring naturally pulls the butterfly shaft towards it, to the left. That can cause the wear you've found if the butterfly plate was already installed tight before the other parts were installed on the shaft. The "fix" is not adding a shim but is to center the butterfly plate in it's slot mount in the main bore. There is a small amount of side to side play there. You loosen the butterfly plate mounting screws, leaving them just snug, then open the butterfly plate/shaft fully and let it snap closed. Do this several times then re-tighten the plate mounting screws. This will center the plate in the main bore for you. I can't say whether yours is worn enough to cause any problems. I think only running it is going to tell you that.

 

[Mailman]

Thanks for the input. That's good information. I kind of figured I wouldn't really know the impact of this until it's up and running.
Btw , the way you described setting the butterfly by letting it snap closed a few times is exactly the way I did it. It just kinda naturally seemed the right thing to do. Haha