correcting lean carbs on 1980/7

[kwipmentkrew]

Greetings . Just bought a 1980 R100/7 . I wanted to know about recommended jetting changes to correct this condition. If you know the recommended parts or a person to contact to find out that would be very helpful. Thanks tom

[20774]

Tom -

Technically, I don't think there is such a thing as a 1980 /7...it's a bit murky... This page says that the /7s were only 1977 and 1978.

http://www.ascycles.com/history_r100_7_data.aspx

This page says the R100T was late 1978, 1979 and 1980.

http://www.ascycles.com/history_r100_t_data.aspx

But that's beside the point...:p

Do you know the carb numbers? That will tell us what the recommended sizes and settings are... There was a previous thread:

http://www.bmwmoa.org/forum/showthread.php?t=26634

that provided a link to a site where such information could be found.

Bing would be the first choice for parts, although any dealer could get you what you needed. Bing sells a good booklet which has all the numbers as well as good parts listings and descriptions on how the carbs work.

[kwipmentkrew]

Kurt, thanks for the guidance. I know the bike is titled as a 1980 r 100. Got this info. also: carb # is 94/40/110. Idle jet is 45, upper jet is 266 and the jet at the bottom of the main jet assembly is 65. Needle position is unknown as I can't find the way to get the needle out. Unlike any other bing or other carb I have seen and I haven't found any help in explaining needle removal. Probably a trick or a factory tool. Appreciate any help. tom

[20774]

Tom -

Matching carb numbers are 109 and 110. Sounds like those are the right jet numbers...except that the main jet should be 165.

As for the needle removal, I found the following on Snowbum's website:

"Later Bing CV carbs have a screw in the top of the slide. Remove the central flat-head screw from inside the slide, and turn the slide over. The needle should fall out the top into your hand, with a little clip on it around one of four positioning slots."

Clip position is nominally the 2nd position. That would be measured from NOT the pointy end but from the other end.

I have the earlier type which are turn-and-pull/push. Even the Bing manual doesn't even show the later type.

HTH...

[kwipmentkrew]

Kurt. Just ordered a 268 needle jet and new jet needles along with all diaphragms and o rings. The bing agency was very helpful and this should get me on my way. Thanks for all the assistance. Tom