fuel problem?maybe?

ok let me start by saying that i am not a bmw tech but i'm pretty decent at keeping my little boxer going.ablut 50 miles into the trip to lima she started losing power.and using a lot of gas.(30 mpg or so).the next morning we checked the points and found out that they had closed up some,so we reset them.took off again and the bike ra better but it still made no power and it was still using a lot of gas.we stoped at the bmw shop in st.louis and bought an air filter and saw an immediate difference now.she will turn 4,000 rpms now.still using a lot of gas though.the next day we were at the rally and asked the guy with the mobile shop if he could look at it and he said that he was really busy and to take the jets out of the carbs and clean them real good.well the main jet on the right side was so clogged that i couldnt even see through it.so we cleaned both jets and put it back together.it runs ok but not like it should.on the way home we stopped in nashville and replaced the two o rings on the jets and noticed that the left carb (the one we didnt really have any problems with)had a bunch of black stuff in the bowl.the bike runs ok i guess but it will not rev higher than 4,000 rpms and the power falls off above 3500 rpms.we think that the fuel hoses (new by the way)are the black stuff in the bowls.i think ill call bing and talk to them.maybe the diaphrams? sp?is this fuel related?or could it be something else?

Layton said:

is this fuel related?or could it be something else?

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From the sounds of it, that bike needs a complete tune-up. Don't even waste your time trying to fix any one problem at this point.

Maybe a long shot but one time I found the rubber(?) gaskets inside the petcocks were disintegrating and making little black stuff that was plugging up the works - making it starve above about 4000 rpm. That wouldn't explain the poor mileage though.

John

Sounds like your carbs are over due for a rebuild. I'd take them apart, clean them thoroughly and replace all needed parts. That aside, I was getting in the low 30's when I bought my bike (88 R100RT), which turned out to be (in part) a bad coil. I replaced the coil and got a substaintial increase in power. My plugs constantly showed a rich mixture regardless of mixture adjustments. Like previously mentioned, I would start with giving the bike a tune up.