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jim in the north
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I have had a problem twice now with gasoline pouring out of the RHS carb overflow soaking my boot in gasoline. You don't realize there is a problem until you smell gas and look down to see the gasoline drizzling over your boot. Fix is to pull over, shut off the petcocks and drop the float bowl, then give the float a lift with my finger then reassemble and off I go. This has happened only twice and only following a full throttle run up a long hill or repeatedly gunning it coming out of curves. Does anyone know what the problem might be? I can ride all day at a steady 70 mph no problem.
Jim

schrader7032
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VBMWMO #7032
San Antonio, TX
Joined: 10/27/2006
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Jim - Did you notice any

Jim -

Did you notice any debris in the bottom of the float bowl? It's possible that the debris is getting on the float valve seat and not letting the valve seat to cut off fuel. My /7 has small screens in-line...not true filters but does catch the bigger bits. My red coat is flaking on the tank...something I'll have to deal with.

Another possibility is that the float doesn't move up and down freely...maybe something is restricting the movement...doesn't take much to keep it from rising. How are your carbs oriented on the bike? I remember hearing that they should be tilted in slightly at the top. Possible reasoning for that is that going around turns, if there's any side forces, the float would be in a better position to resist getting stuck.

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

jim in the north
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r100rt carb overflow

Kurt,
There was no debris in the float bowl. Interesting idea about the carbs needing a slight inward tilt. Mine are pretty much straight up and down. I will give them a bit of a slant. Easy to do.
Thanks for the tip.
Jim

khittner
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How old are your floats? If

How old are your floats? If they don't float so well anymore (the alcohol in your fuel will toast them eventually), the float needle won't shut off the incoming fuel flow adequately, debris or not, and the carb can overflow. If the floats are brown, they've probably served long enough.

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Konrad

jim in the north
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r100rt carbs overfow.

Konrad,
The floats are probably original.
I will take a look.
I thought that they were brass and they seemed to be in good shape when I had the carbs apart for cleaning and new gaskets etc last November. I doubt if it's a bad float but you never know. I gave the RHS carb a slight tilt inward so it matches the LHS as suggested by Kurt. I had never really paid enough attention to the carb angle before. Maybe that is the problem. We'll see.
Jim

schrader7032
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San Antonio, TX
Joined: 10/27/2006
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Doubt the floats are

Doubt the floats are brass...you're thinking of /2 floats. They should be a tight cell foam, usually white. If they get yellow, they might be deteriorating and possibly not floating.

Ways to check if they're floating normally:

- bike on center stand, turn on petcocks for about 10 seconds, then turn them off. Remove each float bowl. There should be around an inch or slightly less of fuel height when measured in the center of the bowl.

- if you end up removing the floats, drop each one into a small container of gas. If they float with about 1/3 of it above the surface of the fuel, they're floating reasonably well.

Be careful when you go to remove the floats. There's a pin that spans the two bosses and the float is hinged off that pin. The pin is knurled on one end. When removing the pin, the knurled end is removed first. Also, protect the bosses and don't apply a lot of side pressure to them...they can break off.

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

khittner
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If they're original, and

If they're original, and brown enough to look like brass, they've served their time. Buy some new ones---they'll be white. There are some who opt for "alcohol-resistant" floats from Bing; they sound like a self-evidently good idea, but reviews seem mixed.

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Konrad

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