Vintage BMW Motorcycle Owners

Happy to report that the leak was in fact the fuel lines! Thanks for the advice everyone.

I'm going to try fuel line perhaps the simplest thing of all was the problem and I was trying to make it complicated! Thanks for all the advice folks.

-drpetemurray, what is the float choke reservoir cylinder? Another note is that the cloth braided fuel line entering this carburetor is saturated with gas I'm wondering if this is related to the leak. Could the fuel in the line even after petcock turned off be dropping into the carb even with float ...

Its a good suggestion. The leak started randomly without having taken the carb apart whatsoever. I replaced o rings gaskets and float needle only because I thought that would help solve the leak. It's a strange one. I appreciate everybody's thoughts we'll figure it out!

Right that's whats confusing the fuel level in the bowl isn't whats causing the leak its that fuel is dribbling from that small hole as described above and I suppose running out through saturated gasket and outside of bowl.

Ive measured 16mm of fuel in the bowl. The other carb that doesn't leak also measures 16mm.

Upper part of carb body. Attaching a photo of carb body not my carb but same model I think. Fuel dripping from what appears to be a port near the brass tube in the upper left of carb. Only visible with the gasket removed. Floats and needle stop fuel from entering everywhere but here.

Hello, I'm new here... I have just replaced o-rings, cork bowl gasket and float needle in leaking Bing carb. I thought float needle was the issue but upon further inspection it appears that fuel leaks from a tiny hole in the carb body near the brass tube (front left corner of the carb looking down f...