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Utter Disbelief 1957 R60

72r60/7

13278
I have 1 leaking (only 1-Thank u God) Float chamber. No news there, apparently. I think the type float chamber is called “center top” float needle as opposed to the needle and lever offset in the float chamber top.

I was looking for the Vintage Display at the MOA National and smelled it before seeing it. Just followed the smell till it got to be liquid and a little further found Old bikes at the end of the trail.

Everyone says “They all do that”. Ok fine. [How does one fix it. This is the disbelief part.]
I’m not very good at estimating the distance to arrival/engine shut off and then turning off the petcock.

I’ve been around BMW motorbike people for many years and have come to accept eccentricities. And I know the basic German approach to engineering and basic rational of fixing things that didn’t work. They are especially good at fixing things that do work, and ignoring those things that don’t. You can’t tell me that the German riders in the ‘50’s would accept leaking Carb Floats.

There are bound to be people on this planet that get these Carbs to stop leaking. I realize there are but I don’t think they are gonna let the rest of us know how they do it. (German “Smug” and comes with some Bike keys).

I have tried more than several methods, some involving new parts. Just can’t seem to get it to stop.

Break your silence and tell us how you did it. You know you’ll feel better.
I’ll be “utterly” eternally grateful.

Charlie
 
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Charlie -

Can you tell us what are the new parts you've used?

I don't have any issues with leaking carbs on any of my bikes. On the /2 and older bike, I do have a point where I shut off the petcock before arriving at my stop. The purpose of this is to prevent the heat from the engine to continue to expand the fuel into a leak. Basically, you're pulling down the gas in the float chamber in order to allow for expansion room.

What about your floats? Are they still the original brass floats? Note that brass has been work hardened and is brittle. Over time, the brass cracks allowing gas inside the float which then sinks...certainly not good. Vech at Bench Mark Works sells plastic floats suitable for ethanol fuels.

Then there comes the issue with the float sealing process. Of course, the float pushes the needle up into the seat in the top of the carb to stop the flow of fuel. If the petcock is off, there can be no flow anyway. Does your petcock need to be reworked? Also, the float needle is a long rod and the bottom end of that rod runs in a tube built into the bottom of the float bowl. Sometimes that tube can get corrosion in it which then doesn't let the float needle/rod move freely up and down. If it sticks down, the float doesn't seal on the seat.

You can look at the seat in the float cap and use some toothpaste or the like on an eraser to polish the seat a bit in order to get rid of any roughness.

I would think any of those things would eventually get you to a point where there's no leak. But first, I think you need to get more consistent at turning off the petcock in advance of your stop. If the petcock works well, then there's no potential for fuel leaks. Unless you have some cracks or holes in the bowl.
 
Yep. New plastic floats and new needles. Tooth paste, by hand, with old needles and just a touch with the new needles. I don’t think the needle seats are brass, which may work better. Have heard of using a 0.??? “ drill bit in reverse to help with the needle seat.

Would like to think that I am on the verge of both carbs sealing,🙂, but maybe I’m on the verge of both leaking.😠.

You are right, the petcock could be the root of my ill, but does seem to shut off the fuel w/o leaking for the short term.

Charlie

(May need to just try everything again, and again.)
 
Im in a state of temporary relief. NO leaking Float Bowls.

I used the “1/8” drill bit turned backwards by hand method” a little more aggressively one more time on the float needle seat and stuck my tongue out of the other side of my mouth while doing so.

Just to make sure I don’t know what repaired the leaking float seat, I put an old Float Needle in an electric drill an turned on low speed for maybe 15-30 seconds after the reverse 1/8” bit method. I don’t like trying to solve a problem by doing more than one thing at a time, but I held my tongue this time and did two things.

Need a little more time to prove it is not a very temporary fix but it has allowed
me time to address my next problem on a ‘57 R60, which is a sticking carburetor slide.
Already talked the the Bing Mother Ship in Kansas.

Charlie
 
You don't have to be "uterly eternily grateful"

The motorcycle is a little over 50 years old. They leak, stink and sometimes leave a nasty oil stain on the pavers, floor or parking spot. The simple and most effective way to address a leaky float bowl after shut down is to shut off the fuel petcock about a minute before you pull the key and shut off the motor, I've been doing it for years and it hasn't hurt me one bit.

I will apologize in advance if I get a little snippy but some owners insist that their bikes should be perfect, not leak, not stink and start on the first or second kick yet they will not take a few hours, some common sense, hand tools and get their hands dirty to figure out how things work and sometimes don't work with these old bikes.

I've met more than my share of /2 and pre /2 owners who paid way to much for the "cool old BMW" and have endless problems with electric, stink, leaks and other problems and end up complaining about the brand or a certain repair shop that won't help the all the while all they have to do is use a little common sense and practicality.

Simple solution options: 1. Pull up, park, center stand, shut off fuel petcock, let it run one minute, shut it off.

2. Estimate your distance to park, shut off fuel petcock 2500 feet prior to parking, park and shut off.

3. Spend a crap load of $$$, frustrate vendors, not fix the problem, bash the old BMW's because the leak and stink.

4. Sell it and buy a fuel injected bike under warranty. The R Nine T bikes are incredible, I have two models that don't leak a bit along with a little more than a handful of
petcock pre "95 and Pre '70 bikes that don't leak. Some even have the EverBest petocks they had when new, Yeh I rebuilt them.

My personal advice would be to learn about the bike, follow a basic & easy shut down routine and enjoy owning and riding it. But if its a pain in the butt, smelly and worries you about the garage burning down you might want o to sell it and get a fuel injected bike under warranty.
 
Sticking carb slide?

Make sure your throttle cables are routed correctly, if they are pull the slides out and clean them and the bores with some 2000 grit wet dry and WD 40. Check your advance weights also because they will mess you up every time to.
 
Bing tech/owner suggest sanding slide for my situation as the Carb bore is hour glassed shaped warped due to metallurgy. I was going to do that, but asked Bing (owners name ?) for additional information and conformation.

And the other Tangent:

“Eternally grateful” was stretching it a bit but I am greatful to who said use an 1/8” bit by hand backward.
It’s not like I would have though of it myself.

You are right about expecting too much from 60 yr old machinery. I’ve owned bikes (BMW’s) for 45 yrs and nothing surprises me about their engineering and, in reality, no one can blame them for how that design matures. Though I never want to accept “they all do that” when most don’t.

I also don’t take things about this interest or hobby, as it is, too seriously. It’s supposed to be fun. When it stops being fun, I don’t do it anymore.

Charlie
 
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