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jlibby
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Joined: 05/31/2006
Posts: 16

I just put the lever tops on my Bings. It seemed to have stopped the leaking carbs, but I just went out and checked again and sure enough a smaller leak. Should you not be able to leave the gas open on these old machines without expecting a leak?

Another question if I may.... The bike idles like a champ, but when I try to take it out for a spin, it doesn't seem to want to get going. I have to rev it up a lot just to take off. It sputters, pops, etc. I really have rev it and ride the clutch just to take off. I know this isn't normal. Is there something simple I can check or do I have to admit temp. failure and take it into a shop? I appreciate all the help. thanks

schrader7032
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VBMWMO #7032
San Antonio, TX
Joined: 10/27/2006
Posts: 6896
Any suggestions for a newbie?

Personally, I don't rely on the float to shut off the gas. I usually try to turn off the petcock about 1/4 mile from home and then leave it turned off.

As for the slow starting, at first I was wondering if your clutch might need adjusting or has worn thin. But you say it pops and stutters. Sounds like the basics, timing and/or carb settings.

Kurt in S.A.

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Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

jlibby
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Joined: 05/31/2006
Posts: 16
I think I know where the leak is coming from....

I just laid under the bike with a flash light. It appears as though the leak is coming from the gas/air mixture screw. Should there be a gasket in there? When putting in the bing full rebuild, I had 2 small gaskets left over that I could not find homes for. I took off all the old ones, and replaced with the new ones, but still had these 2 left over. I thought they must have put in extra. Are there any hard to see gaskets that are not visible without ripping into the carb further? thanks

Darryl.Richman
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VBMWMO #6285
Surf City, USA (Santa Cruz, CA)
Joined: 10/27/2006
Posts: 2185
Any suggestions for a newbie?

It is an oft repeated statement that Bing is German for "Leak". Just like Kurt, I try to run the level down in my float bowl before stopping the motor, and always use the petcock to stop the flow of gas.

After you stop the motor, the carbs will heat up from the residual motor heat, which, without the cooling wind, rises for a while. If you don't run the gas in the float bowl down a bit, the bowl will be full and the heat will expand the gas, draining it out through the fuel mixture screw. The escaping gas has to go somewhere, and leaking on the ground is better than having it run into the head and, if the intake valve is open, into the cylinder.

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racer32
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Joined: 07/16/2006
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Any suggestions for a newbie?

OK-first off, I'll tell you this: my experience with BMW Bings is limited. I have a /2, but it's been mothballed and I haven't had the carbs apart in a LONG time. I have however had many years of experience with the Bing 54's that come on dirt bikes. They all seem to leak a little. The poor off-idle throttle response sounds to me like a clogged pilot jet. It's been 7-8 years since I had the carbs apart on my /2, but I believe it is accessed from underneath the carb, offset from the main jet at the center of the throttle body.

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