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R69S battery

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Flx48
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Re: R69S battery

Post by Flx48 »

James, my thought has been that perhaps it had to do with the delivery market-
In my case the '60 R69 (big battery) was a B&S bike, while the '56 R69 (small batt) was a Canadian delivery.
Maybe home market and others got the small battery, and Americans got the big battery along with the big seat, big bars, and big whatever else.
Just a thought.
Other than that, perhaps the old song about the factory used up whatever they had on hand, so both are correct...
Best-
George

Wayne J in MA
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Re: R69S battery

Post by Wayne J in MA »

My late Jan. 1962 R69S has original large battery. It came in through B&S.
'62 R69S, '71 R75/5 SWB, '78 R100S Motorsport
Westwood, MA USA

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schrader7032
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Re: R69S battery

Post by schrader7032 »

Wayne, do you still have the original battery in the bike from 1962? That's impressive! :lol:
Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2
Fast. Neat. Average. Friendly. Good. Good.

sherman980
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Re: R69S battery

Post by sherman980 »

So thought I'd do a little more digging and went to Mark Huggett's site to search by part number for application. Mark has the most direct ties to BMW corporate info and is responsible for BMW's efforts to support the vintage BMW parts market. His database isn't perfect, but it is about as good as it gets. Entering the part numbers for the batteries doesn't tie them to applications as I was hoping. When I enter the part number for the small battery tray, it list's it for R50 (01/55-08/60), R50S (08/61-08/62) and R50/2 (01/61-08/69). When I enter the part number for the large battery tray, the application just comes up as USA. So not any definitive help there.

Over the years I have owned at least 20 plus Earls fork bikes. As best I can remember - not as reliable as it once was :lol: , all of the pre 1960 bikes had small batteries and all of the 1960 and later bikes had large batteries. (Maybe the break point was 61?) Thinking Kurt might have nailed it with his post about the generator change. There also appears to be some relation to the market the bike was delivered in based on both Huggett's limited info and the markings on the parts diagrams I referenced earlier. And James, I just finished a very original 1962 R50S restoration that I'd owned for nearly 30 years and it had the large battery configuration. Can't say it definitely came from the factory that way, but, if I had to guess, I'd say it did. I have some R50S photos I got from the factory somewhere around here and will update if/when I find them.

So no definitive info right now, so probably best to send a note off to the factory to ask. And for those who think that BMW simply used whatever was in the parts bin to build bikes without paying attention to what a specific model called for at the time or not documenting a necessary change, while it may have happened, I doubt it happened very often. Been to the factory multiple times and have seen and reviewed actual production information from back in the day that still exists. Builds for each model were quite specific. Describing German manufacturing as "haphazard" would be less than accurate!

Chuck S.
Thanks.
Chuck S

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Re: R69S battery

Post by 808Airhead »

I made a mistake,I SHOULD have said "/2's have the bigger battery!".....I own a pair of "/2's" and forgot momentarily about the esoteric minutia that comes with the early bikes....If you have the bigger tray,then it is easier to source a nice size 6V that will fit in there. For the smaller batteries I have used anything from CCTV batteries, alarm batteries to childrens ride along car batteries with mixed results in the smaller housings. HAs anyone else purchased the bigger shell from Tim? They are very nice.
Thomas M.
R69S - R60/2 - R67/2 - R51/3 - R69

Wayne J in MA
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Re: R69S battery

Post by Wayne J in MA »

schrader7032 wrote:
Mon Oct 25, 2021 7:06 pm
Wayne, do you still have the original battery in the bike from 1962? That's impressive! :lol:
No, I meant to say that it has the larger tray for the bigger battery. It would be impressive, well maybe not so much since there would probably be a lot of corrosion around and under it.
'62 R69S, '71 R75/5 SWB, '78 R100S Motorsport
Westwood, MA USA

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jwonder
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Re: R69S battery

Post by jwonder »

I got a reply from the BMW archives for my R 50 S (January 1962 build) and they state the smaller 8ah battery was mounted in mine. Now, mine came to the USA destined for either USA or Canada (not sure which as the bike came out of Canada to the previous owner).

Archives answer:

Dear James,

these are the battery sizes R 50 S.

This is the battery your R 50 S should have: 8 Ah
battery 8ah.jpg
16 Ah Battery (Police version):
battery 16ah.jpg
James Wonder
Vice President, Vintage BMW Motorcycle Owners
2022 BMW Friend Of the Marque
Long Island, New York

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vechorik1373
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Re: R69S battery

Post by vechorik1373 »

In Europe, the bikes were supplied with a battery group B49 (that is the square base battery used in the plunger frame bike) BUT bikes exported to the US used the B38 6a which is the rectangular one. The rectangular sealed battery we supplied is a 1/2 inch smaller in all three dimensions, and has male connections. They work, but are not really designed for motorcycle use. The connections, between the cells are not robust enough, and can break from vibration or road shock, in that type of battery. But as I said, they are cheap, and work.
Vech
Technical Adviser, Former owner, Bench Mark Works
662 312 2838 cell 9 am to 4pm CST PLEASE!

maddrobh
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Re: R69S battery

Post by maddrobh »

I am amazed at the way this thread has run! Interesting. Anyway, this post just to that I’m very pleased with the new battery, the neutral and charge lights are now bright when I switch-on the ignition and the battery charges well. Winter job is to do the valve and rocker clearances and maybe a compression test.

Back in August, I took the bike on a well-known local rally, the ‘Cairn o’ Mount’ rally, expecting it to be the only R69S there. I was amazed to see a beautifully restored ?68 R69S with new Steib sidecar. The engine had been rebuilt by an aero engine specialist, sadly now retired.

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vechorik1373
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Re: R69S battery

Post by vechorik1373 »

I forgot to mention, that if you want to have the bike look 100% correct, the B49-6 square base battery, in the original rubber case, with a lid is still available. I had them in stock, when I owned Bench Mark Works. MAX bmw has them in stock now. But they are a wet acid battery, with vented caps. They are not a sealed AGM battery.
Every one worries about acid spraying out on the paint. IF your charging system is working properly, a wet battery won't spit acid out. The way to check you system is to use an analog volt meter, (NOT a digital ) and you should see not MORE than, or not LESS than 7.2 volts if everything is working properly. You can't use a digital meter because if you have an original electro mechanical regulator, (which causes the voltage to oscillate up and down, because that is the way an original regulator works, and a digital meter takes samples way too fast, and the numbers will just tumble)
So don't fear the use of a conventional battery IF you charging system is working properly.
This is the part number for the correct in appearance original style battery
61 21 8 042 025 B49-6 square base 6v 10a battery original style with lid 1930's - 1954
Vech
Technical Adviser, Former owner, Bench Mark Works
662 312 2838 cell 9 am to 4pm CST PLEASE!

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