Re-Bush for BS34?

[Notmyrealname]

I have searched and searched. Can't find any thing. Does anybody know of a shop or somebody that installs new bushings in BS34 carbs? The carb body is worn and new seals aren't fixing the air leak on the butterfly valve shaft. Seems like the carb body could be saved if some bronze bushings were installed where the shaft goes thru the aluminum. Thx

 

[gggGary]

Gathered all the parts n tools but never tried to do it.
It's pretty fussy work and replacement carbs new and used are "dime a dozen"
There are (were) shops that did rebushing of Solex carbs for cars.

https://www.partsklassik.com/p-987-throttle-shaft-bushing-solex.aspx

 

[Its been a long time]

Definitely do-able in theory. Whether there's enough meat remaining in the carburettor casting after boring* it will be what determines whether you can actually do it or not. There's plenty of suitable bushes readily available in standard sizes so there's probably one out there that will do the job.

* the holes obviously need to be in alignment left to right so it would need a reamer or similar passing through to get the holes spot on aligned. Any misalignment would result in the butterfly shaft not rotating freely. Then there's a question about how the butterfly shaft seals will fit.

 

[Notmyrealname]

Maybe a business opportunity for someone with a milling machine. Thanks guys. I had to ask before I went with the vm34's

 

[gggGary]

I looked and sure enough AZ. Badly worn shaft bushings after the first BS38 bushing length revision in 72 seems to be a desert (grit, dust) problem.

 

[Notmyrealname]

Before I got the bike it lived in central Utah. High desert climate. Also cold/hot dry and dusty. The guy I bought the bike from gave me a ton of spare parts. In there was another set of BS34's. I thought they might be better. They looked newer, but also leaked around the shafts. I've fattened up the main jets and put a size smaller air jets in. They are better, not perfect, but will do until I get the new carbs. Probably a lot of these bikes with leaky shafts. Not one of the best designs from Mikuini.

 

[gggGary]

You using the factory seals? (only thing that works)
Usually just the bush that the throttle cable pulls against is bad.
Bought a set of carbs from AZ one time, learned a lesson about desert carbs I did.

 

[Notmyrealname]

Yes factory seals.

 

[GLJ]

You using the factory seals? (only thing that works)

I've used Mikes and some random ones from E-Bay with no problem. But then I pack them with high vacuum grease. I guess ignorance is bliss.
If the carb bodies are worn too much nothing will seal for very long.