Vintage BMW Motorcycle Owners

Tommy,
Idle jet is in its place.

Next
I would remove gas from both carbs
Install floats with float needles
make sure they are the same height with no gas if not they may not be dropping down far enough and the high side still has some crap in the lower float guide
if ok install lever tops turn on gas until it starts leaking and then turn off gas
remove both lever tops and see that both sides have the same amount of gas in the float chamber
I would guess that the left side is higher than the right side not shutting off too late or has a bad float needle but most likely some crap above the float needle
you can not clean this by soaking it or blowing air into the intake on top of the bowl cover
you need to remove the float needle and then clean it
Also compare both float needle levers to see they close in the same position
Tommy

Thanks Tommy.
Will try this also.

How can I remove the floats needle? I think it is soldered there in some way.

https://www.bmwclassicmotorcycles.com/p ... arburetor/

You need to remove the split pin # 39,then the lever piece #38 can be removed and then the float needle # 37 can be removed
Now you can inspect the float needle and clean the gas inlet port
Best to put lever top in a vise (lightly) and use a small punch or maybe a small nail to drive the pin out
Be careful not to bend the float lever

Tommy

Thanks, will try it this evening.

BTW - Does this needle do anything at all, other than lead and center the float?
I don't think that there's an opening on the lower well or in the cover one.

I also enclosed some pictures, I really can't see any dirt on those parts

Only now, after reading again your post, I realize that maybe we are talking about different parts.
I refer to the float - and you mean the slider? Am I right?
Because the brass float's needle is in my opinion only there to act as a lead or center piece, It does not divert petrol anywhere. The are no holes drilled on the bottom of the brass float chamber.

Micha wrote: ↑

Tue Apr 20, 2021 8:03 am

Only now, after reading again your post, I realize that maybe we are talking about different parts.
I refer to the float - and you mean the slider? Am I right?
Because the brass float's needle is in my opinion only there to act as a lead or center piece, It does not divert petrol anywhere. The are no holes drilled on the bottom of the brass float chamber.

The lower hole in the bottom of the bowl is clean and looks good as shown in your pictures
I never mentioned slider in any of my posts
I did mention the floats on both sides so I think you read that as slides
Tommy

I assume that the needle's jet bottom in the carb's body is not ok.
The needles have been swapped but it is still leaking from the same side carb.
So I assume that the bottom well of this needle, inside the carb is damaged.
Question is, how can I fix it? After all, this is a conical needle.
My wife is already looking for a place in a lunatic asylum for me.
Thanks a lot and a nice weekend everyone.

EDIT
Of course all what you guys said - I did. Including swapping floats and covers. All are in the same height. All have same needle length.

Another edit: I was surprised to find a rubber tip on my needle, never the less, it look quiet all right, what do you think?
Is swapping needle tips a good idea? Are the metal ones available today - better?

Maybe lowering the position of the slide needle can help?
I think it is now in 2nd or 3rd hole, I can bring it down to the 1st one.

IN MY OPINION-> The ONLY way to really get a carb SPOTLESSLY clean is to take it completely apart & soak it in Gunk Carb cleaner AT LEAST overnight. This often has to be done a couple of times to get everything out off all the little bore holes. Someone mentioned u could be getting contaminated gas from the tank. Did u flush it & refill with fresh gas? Did u clean the fuel strainer ?