Hello, and a first Q regarding old carb numbers

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schrader7032
Posts: 7393
Joined: Fri Oct 27, 2006 3:00 am
Location: San Antonio, TX

Hello, and a first Q regarding old carb numbers

Post by schrader7032 »

Zeke -

This must be for the R69?? You have it basically right...the 26 is the diameter of the throat or possible the mating flange with the head. You might want to consider getting a book from Bing that describes all of the carbs and gives internal parts breakdown...costs maybe $10.

The book indicates the 9/10 were for the R68 and R69 with various jets and needles along with idle settings. The book does show models 85/86 for the R69. Looks like there's a different number for the slide between these two sets of models. That leads me to think that a body for 85/86 cannot be used with the slide for the 9/10...I'm not sure...

Comparing internal parts/numbers for the /2 bikes, like the R69S especially the early models, there seems to be some similarity with the R69 carbs. Looks like early R69 and R69S will interchange and the older R69 and R69S carbs will interchange.

Besides getting the book, you might want to contact Bing...website is http://www.bingcarburetor.com.

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

Zeke
Posts: 5
Joined: Fri Aug 10, 2007 8:59 pm

Hello, and a first Q regarding old carb numbers

Post by Zeke »

Yep, its for my '55 R69. When I last talked to Bing on the phone, they did offer me an exploded diagram of my carb, without any explanation or instructions, for $15 (which I took, but $15?). I was getting the rebuild kit from them, but they didn't mention the book at all. But after rebuilding one carb, I found that the right one had a warped body, and had to start looking for options. At first I thought it was just the slider, but it was the body itself. Do you think this is common?

"Looks like early R69 and R69S will interchange and the older R69 and R69S carbs will interchange. "

Really? Wish I had known that and which numbers they are while I was on the search. But then I might have given up and settled for something other than an original carb body (being a somehwhat basically lazy kind of guy).

Are you able to tell which carbs are interchangable with which, or which bodies are the same and which parts vary? That would be highly usefull info to have on hand.
Zeke Griffin
'55 R69, '66 A65L, '69 T120R, '69 T100C, '70 Commando,'71 A65L, '74 R90S,'74 T500 (2), '98 FLHTC, '00 R11RT, and a few boxes of various parts awaiting more members of their genus prior to assembly.

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schrader7032
Posts: 7393
Joined: Fri Oct 27, 2006 3:00 am
Location: San Antonio, TX

Hello, and a first Q regarding old carb numbers

Post by schrader7032 »

Zeke -

I can only go by the major part numbers in Bing's book. I would think that the slide is a major deal whereas the jets and other specs wouldn't be so critical. Maybe somebody else will have more direct experience. I could scan the one page that has all the specs and you could look at it. PM me for an email address and I'll see what I can do.

Another option is sleeving the body. I believe that has been discussed on this forum. Allan Atherton most likely present information on the company that does this sort of thing. Triton?? That might be a good way to go, so you can keep the original parts with your bike. Try a seach...if you come up empty, let me know and I'll track down where I saw it.

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

Zeke
Posts: 5
Joined: Fri Aug 10, 2007 8:59 pm

Hello, and a first Q regarding old carb numbers

Post by Zeke »

Thanks Kurt, I'm on it.

I had the option of a few various carbs when I was searching, but found an original along the way. So now I have an extra body which could be resleeved I suppose. And if I ever do a complete restore rather than the refurbish that I have underway, I will do something like this (original equipment is afterall the real deal!). That was an interesting topic when I read it recently.

I am hoping to get some kind of real understanding of how these numbers work and what they mean, since I've found that most folks don't have a clue (at least around here). Just think it would be handy down the road somehwere.

Thanks again.
Zeke Griffin
'55 R69, '66 A65L, '69 T120R, '69 T100C, '70 Commando,'71 A65L, '74 R90S,'74 T500 (2), '98 FLHTC, '00 R11RT, and a few boxes of various parts awaiting more members of their genus prior to assembly.


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VBMWMO
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Joined: Sun Aug 23, 2009 7:49 pm

Hello, and a first Q regarding old carb numbers

Post by VBMWMO »

After reading so much of your very helpfull posts, I thought it about time I said hello and thanks for having this site and sharing so much information. I certainly have found over the years that the old Beemer community is incredible in this way, and this group definately seems to be no exception.

So, on that note, one thing I haven't been able to piece together is a complete understanding of the numbering system on the carbs of the old bikes. This came to import recently as I found that the body of my "1/26/10" was warped, and I couldn't rebuild it. What I've been able to parse together so far is that the center # represents the mm, and the last digits designate right or left if they're even or odd (9=left, 10=right). But that's about it. While searching for a new body to use, I found a lot of numbers but no one seemed to know (other than occcaisionally which bike they came off) what they indicated or what they really mean (or even more relevantly, which were interchangable).

Is there a system for understanding these little beasts with thier arcane scribbles, and knowing what's what, where they go and which are basically interchangable with which? Can anybody please explain it to me please?

Is this too much for the first time out?

Thanks in advance.
Dedicated to the Preservation of Classic and Antique BMW Motorcycles.

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