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holman2106
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Barry, If you find a supplier for the R11 front brake plate,please let me know. I need one for a 1930 also. Mine is cracked and I was going to weld It up, but found out real quick that it is made of pot metal.
I have some Series 1 R11 questions that I would like to talk with another Ser. 1 owner about. Maybe I should contact you off forum? Thanks,Dan

Barry Robin
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R11 brake plate breaking

dan-
welcome to unobtainium world! quite the E ticket, isn't it?

interesting, isn't it, that the R11/R16 bikes seem to have become the forgotten, unwanted children of the bmw vintage world; parts for every bike bmw ever made are usually repopped by the handfull-even the very early bikes of the 20's and of course, the R12's-but for some reason, the late twenties to mid thirties twins models built in between have fallen into the black hole of calcutta, to mix my metaphors...

if it makes you feel any better about welding your hub, the metal-no matter what you've heard- is an aluminum/magnisium mix, not pot metal; i found this out because i've had to reweld my hub twice now...so make sure that the welder doesn't use straight aluminum, as it's waaaay too soft (yes, i found out the hard way).

and as an open plea to those going to manheim:
i'd be more than happy to pay a finder's fee to anyone who might be interested in shopping for one for me-and i suspect dan as well-all we ask is that it has no obvious cracks or holes. if you don't know exactly what they look like, just take a look at photos; it's hard to mistake them for other models, since no other series bikes ever looked like them.

gee, can you tell i'm a tad half crazy at this point?

dan-feel free to drop a line to me if you need any arcane info on your bike, and in the meantime i'll keep our fingers crossed for both of us.

-barry robin

Darryl.Richman
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R11 brake plate breaking

"holman2106" wrote:

Barry, If you find a supplier for the R11 front brake plate,please let me know. I need one for a 1930 also. Mine is cracked and I was going to weld It up, but found out real quick that it is made of pot metal.
I have some Series 1 R11 questions that I would like to talk with another Ser. 1 owner about. Maybe I should contact you off forum? Thanks,Dan

Dan and Barry, it occurs to me that I should pass along something I was told about my R52, because I think it might also apply to the R11. Please check me on this!

When I was looking at this R52 to buy, I made a list of every detail I could find that was, or might be, wrong. One thing I noticed was that the front brake cable was routed differently than in the factory pictures:

If you look carefully, you'll see that the brake cable runs off of the fork to a boss on the brake plate, and that the lever it actuates is pointed back. In the factory photos, the lever faces forward and the cable runs to where the fender braces mount to the fork.

[img]http://darryl.crafty-fox.com/mcpics/2004/R52/R52%20Info/00004770_M[1].jpg[/img]

I spoke with several knowledgable people and was told that this was an "upgrade". The original routing would cause the force on the brakes to change as the front wheel went over bumps, and could cause the brakes to lock.

Perhaps the R11, with a similar trailing link front fork, has a similar problem?

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Barry Robin
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R11 brake plate breaking

you're aboslutely correct on that-on all points that i'm aware of. the "upgrade" was indeed just that-but from what i've found, it was noticed by the factory almost immediately, and corrected; almost no bikes were released without the fix.

however, no R11/16's that i know of were sold without the backward facing lever-but they still failed, possibly because bmw hadn't yet gotten around to beefing up the plate with the extra ovaloid gusseting (coming off the lever mounting hole) that appeared on the series 5; we know them better as R12 parts...

Barry Robin
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R11 brake plate breaking

darryl-

big oops on my part! the R11 does indeed go towards the front! don't know what i was thinking...exept that i wasn't!
funny how one's memory plays havoc with the facts sometimes...

i'll try to check my facts and my few remaining grey cells twice before i shoot my mouth off next time.

that being said, perhaps i should look into swapping the lever direction to see if it stops the hub from cracking a third time Smile
-b

Darryl.Richman
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Split and moved

It seemed like this topic was running inside another thread, in another discussion area, and was more suited to its own thread in this area.

Anyway, I have to agree, I don't think I've ever seen an R11 or R16 in person. Is there one at the Barber museum?

And how do you find out what is "correct" in each of the 5 series? Seems like BMW made a bunch of running changes.

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Barry Robin
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R11 brake plate breaking

i have to agree with you on this thread highjacking silliness-it did indeed take a turn somewhere strange...

you wrote: "And how do you find out what is "correct" in each of the 5 series? Seems like BMW made a bunch of running changes."

yup, they sure did; but unlike the later /2 and /5's, wherein most parts, though perhaps wrong for that year model, still fit all the model years. i learned from experience on my rebuild that almost none of the '29 to '34 pieces retrofit any other year exactly-mainly because bmw kept beefing up the measurements to make them more stable, a few parts per year.

but hey-at least you have a ton of extras to sell off when the bike's done!

are you scared yet, dan?

holman2106
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R11 brake plate breaking

Thanks for the brake lever information Darryl and I apologize for my untentional part in the hijacking. Yes, the R11 is a hard one to find much information on. The original pinstripping on my front fork is different from anything I've seen in pictures.
Barry, Is your rear fender removable piece held on with one or two bolts?
Is your center stand return spring a coil spring that fits over the pivot bolt or is it a extension spring that hooks on the frame somewhere?
My bike came with Amal twist grips which I think was an option at some point on the R11...any opinion about that?
It sounds like the brake plate is quite fragile and I think I would rather go with a repop for saftey reasons. If they are not available from the Father land, I may make a pattern and have one or more cast.
Would you have an extra carb for an early R11??

Barry Robin
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R11 brake plate breaking

hi'ya dan-

my my; quite a lot of questions there!

well, without pictures or info on your bike, i'll have to be a tad general, but here goes...

on the rear fender: that's almost a trick question-because the answer is three, not two. there's the the single one top of the fender, at the overlapping seam, and then there's one for each side at the end of each stay; these go into the drive shaft housing on the right side, and into a factory drilled hole in the frame on the left.

center stand: according to the parts book, it should take both-at least after 1931; there should be a smallish "O" bracket on the left side of the center stand if your stand was made before the 3rd series, and a flanged pin after. unfortunately, when i first got my bike, this spring set-along with the battery bracket-were the only pieces not original to the bike, so i had to cheat a bit by using a modified R12 battery tray; these were indeed used on the R11, but not untill the 5th series in 1934.

the twist grip (and there were two or three versions, i belive) was indeed an option as far back as 1930, but only officially for the R16; the R11 kept the dual levers untill '31 when bmw swapped carbs to the single sum. my opinion on them depends on if you'll be showing it in a points situation or not. if so: if you still retain the original handlebars, see if they have the factory holes for the through and through mounting of lever sets. if they do, there you have it. if not, mount on the amal or more correctly for the R11, from magra.
that being said, the twist grip, once properly set up, is miles ahead of the hokey levers. but then i'm crazy enough to drive around with my levers, so don't listen to me; one can get used to anything.

now, this is just my opinion, but i'm about to commit heresy: in the real world, sometimes using "wrong" parts is just fine, especially when the right ones don't exist; think about this: there's supposedly only about 150 complete running examples or so of the R11 left driving around; the only people who'll ever know which parts are wrong for your exact year of manufacture are you and about six other people. i sometimes ended up knowing more than some of the judges! with a model this goofy, i feel it's more than fair to say, when asked: sure, you gonn'a get 'em for me? i'd love to use the correct 1931 parts, but but i can't get them; they seem to have been melted down in WWII and no one's ever made repros...
if this set-up is just for you and your local bmw friends, nobody but you will ever know that your example should have had levers instead of a twist grip-especially when bmw swapped parts every other month...

carbs: another trick question: by late 1930 they were already gearing up for the 1931 model, so your bike might be on the cusp-check to see if your frame numbers are early or late.
if early, your carb should be one made by bmw, with a dual barrel float, attatched to an intake manifold (using magra levers). if later, you might be able to mount the fancy dual carbs by amal/fisher. these will bump up your hp considerably.

if you've any pictures i could see, feel free to send the over to my email directly. i could be more specific.

-barry

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R11 brake plate breaking

darryl-

you asked "...And how do you find out what is "correct" in each of the 5 series? Seems like BMW made a bunch of running changes."

just read off the part numbers stamped on any given part-then look at a catalogue picture.
if you look at a copy of the original parts books-available in reproduction-you can see that unlike the later parts books, it's set up by this clever but needed illustrated chart by part; you just look for the picture-all the various years stock numbers are there-then you can find your existing part number with a check in the accompaning graph that tells you which year it was used in-or with reverse engineering, you can see which versions of each part you need by year, all listed by bmw internally stamped numbers.

for extra fun, you can also use it to find service and replacement parts on your bike done way back then- hey, wait a minute! this part number corrosponds to a year and a half later than my bike! i guess the original owner layed it down so the dealer used the newer stuff...
even some of the nuts and bolts changed numbers and thread counts...!

Darryl.Richman
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R11 brake plate breaking

"holman2106" wrote:

Thanks for the brake lever information Darryl and I apologize for my untentional part in the hijacking.

Don't worry about hijacking a thread. It's easy to fix.

Quote:

Yes, the R11 is a hard one to find much information on.

This is surprising to me, because they made 8300 of them. That's double what they made of the R52, and yet the problems I have with getting R52 parts have nothing to do with availability and everything to do with cost. Wink

Quote:

Would you have an extra carb for an early R11??

Isn't the early R11 carb the same item as on the R52/R62 bikes? There are repops of those available, from Dreher at least.

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R11 brake plate breaking

"robin748" wrote:

darryl-

you asked "...And how do you find out what is "correct" in each of the 5 series? Seems like BMW made a bunch of running changes."

just read off the part numbers stamped on any given part-then look at a catalogue picture.
if you look at a copy of the original parts books-available in reproduction-you can see that unlike the later parts books, it's set up by this clever but needed illustrated chart by part; you just look for the picture-all the various years stock numbers are there-then you can find your existing part number with a check in the accompaning graph that tells you which year it was used in-or with reverse engineering, you can see which versions of each part you need by year, all listed by bmw internally stamped numbers.

for extra fun, you can also use it to find service and replacement parts on your bike done way back then- hey, wait a minute! this part number corrosponds to a year and a half later than my bike! i guess the original owner layed it down so the dealer used the newer stuff...
even some of the nuts and bolts changed numbers and thread counts...!

As I've got you guys surrounded, with my R52 and R12 projects, I may have to get an R11 parts book. BMW is notorious for making running changes as they went, and I bet looking through an R11 manual will explain things to me about my R12, and maybe even my R52...

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R11 brake plate breaking

Quote:
Quote:

As I've got you guys surrounded, with my R52 and R12 projects, I may have to get an R11 parts book. BMW is notorious for making running changes as they went, and I bet looking through an R11 manual will explain things to me about my R12, and maybe even my R52...

i feel like we're in the wagon train circle and you're the apaches...!

sounds like it's a good idea of yours, to get the R11 parts book-if nothing else for the learning curve. try to get the later version of it from the series 4 or 5: it contains all the compiled running changes by series. you can easily see that the series 1 parts are left over R52 (remember, the R11/16 was originally simply an R52 (R62?)dumped in a star frame; the last changes show the bike as an almost complete R12 minus the plunger forks...)

and you wrote: " ...they made 8300 of them. That's double what they made of the R52..."
-ah, but they produced those 8300 over a five year span-and the biggest production year was in 1930 (the smallest was 1931, as the depresion hit germany), while they were still using up existing parts, so all they really had to do was pop out the frames.... how long did they make the R52? '26 to '28?

here's a sidebar: the only reason my bike survived intact is because it had been in a front end collision in about 1933 (based on the replacement parts and some poor welding up of the steering neck); it was dumped in a garage in east berlin and stayed there untill it was unearthed in the seventies. if it were running during the war it would most probably have been melted down along with the rest of those crappy older models that no one wanted...

and yes, the carb is the same as on your R52. they used it untill they switched over to the sum.
i've got to ask: doesn't that constant fiddling with the mixture lever drive you crazy? it did me, so i mounted a sum carb instead (with actual real jets!) and it does indeed perform much better, thank you. i've got enough to pay attention to driving around in city traffic without trying to find my third hand...!

Darryl.Richman
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R11 brake plate breaking

"robin748" wrote:

i feel like we're in the wagon train circle and you're the apaches...!

Sorry, no Indians in my garage.

Quote:

sounds like it's a good idea of yours, to get the R11 parts book-if nothing else for the learning curve. try to get the later version of it from the series 4 or 5: it contains all the compiled running changes by series. you can easily see that the series 1 parts are left over R52 (remember, the R11/16 was originally simply an R52 (R62?)dumped in a star frame; the last changes show the bike as an almost complete R12 minus the plunger forks...)

Are you aware that the R11 doesn't have a "star" frame? I believe that misnomer goes back to LJK Setright's Bahnstormer. Instead, it's a starr rahmen which is just good German for rigid frame. (I always wondered what it might be about a pressed steel frame that made it look like a star...)

Quote:

and you wrote: " ...they made 8300 of them. That's double what they made of the R52..."
-ah, but they produced those 8300 over a five year span-and the biggest production year was in 1930 (the smallest was 1931, as the depresion hit germany), while they were still using up existing parts, so all they really had to do was pop out the frames.... how long did they make the R52? '26 to '28?

So, on average, they produced the same number as R52s per year. Anyway, it seems like there should be a lot of R11s still around.

Quote:

here's a sidebar: the only reason my bike survived intact is because it had been in a front end collision in about 1933 (based on the replacement parts and some poor welding up of the steering neck); it was dumped in a garage in east berlin and stayed there untill it was unearthed in the seventies. if it were running during the war it would most probably have been melted down along with the rest of those crappy older models that no one wanted...

A friend just acquired an R62 motor, trans, driveshaft and gas tank from an estate sale. The dearly departed had bought the R62 in the mid 50s to use to power a boat project. Threw away the frame and other bits he didn't need. I was a bit flabbergasted at the idea of that last part, but my friend pointed out that it was just a 25 year old bike at the time that nobody wanted.

Quote:

and yes, the carb is the same as on your R52. they used it untill they switched over to the sum.
i've got to ask: doesn't that constant fiddling with the mixture lever drive you crazy? it did me, so i mounted a sum carb instead (with actual real jets!) and it does indeed perform much better, thank you. i've got enough to pay attention to driving around in city traffic without trying to find my third hand...!

So far, I have about 30 miles of driving the R52. Right now it's still an adventure, and I love messing with it. It's so... weird, and different, and - yes - fussy. It's bound to get old eventually, I suppose. Ask me when I have a couple thousand miles on it!

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R11 brake plate breaking

i had to smile about your notation about the correct translation of the so called starr frame-wondering if you're tired of having to correct people too?; yes, i've always been aware that it's really german for rigid and not something with five points, but over the years i've gotten tired of informing people that Mr. Setright can't seem to translate german!
com'on now: how many times have you had to tell people? lots, i bet...sometimes i just think that it's easier to think: hey, this conversation's in english with a bunch of english speakers-and though the word's wrong, everyone still uses it, so what the hell...

you wrote:"...So far, I have about 30 miles of driving the R52. Right now it's still an adventure, and I love messing with it. It's so... weird, and different, and - yes - fussy. It's bound to get old eventually, I suppose. Ask me when I have a couple thousand miles on it!"

weird and fussy is a good way to describe it. once you get used to it, it's really just fine-though it's still fussy!

i really shouldn't be too snitty about the mixture lever; i only changed it over because, in the long run, it was too much to want to deal with in san francisco traffic (and now in dublin traffic!)
if you end up mostly taking it out on sunday drives up over highway 17, i wouldn't think there'd be a reason to fiddle with it at all.

i've sent you over a picture of my bike (via your website email). you can plainly see that i've cheated with a few modernizations like blinkers and rear view mirrors. i know it's wrong, but i considered them as safety measures.
is there any way you can post it here for me so dan can get a closer look?

thanks,
-barry

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R11 brake plate breaking

I'm afraid I haven't seen your email. You can send it to me directly by clicking on the little email button at the bottom of this post. My website address gets so much spam, I have a very strong filter on it. You have to leave the [cfweb] prefix on the subject line or it automatically goes in the trash. I can put your photo up on my server, and then I can post a link to it here. I'd love to see it!

I'm having a tech day here at my house in 2 weeks (4/15), and there's vintage picnic on June 11 at Vasona County Park in Los Gatos. Any chance you might come to either one?

I don't consider mirrors or lighting upgrades cheating. I've added a brake light (dual filament bulb, too) to my R12, and will probably do the same for the R52 when I get it over here. I will probably also set up some bright LEDs for tail and brake light functions, around the license plate. These things can be wired in so they are easily removed if one wants to show a bike.

The Kradrider list folks (http://uk.groups.yahoo.com/group/kradrider/) know that it's a starr rahmen. I'm kind of surprised at how much reach Bahnstormer seems to have had; I think it was already out of print when I bought my copy in the mid 80s.

Does your bike also have a twist grip for the timing? That seems weird to me! Wink

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R11 brake plate breaking

i'll try reposting my letter to the PM here, thanks.

i'm afraid i'll have to beg off on showing up at the tech day this year; remember that my bike and i are now about 8,000 miles east of your house. hmmm... maybe if i catch the ferry out of dun laoghire i can get the ferry captin to take a detour!

i've done the brake light refit too (listening here, dan?)-it's a must for driving on the street! without it, one feels like it's only a matter of time before someone decides to notice you've got a sign on your bike that says "kick me". (have you noticed that hardly anyone remembers that holding your left arm downwards means "stopping"?)

on the twist grip timing: i have no twist grips at all-just the same lever sets as your R52. the only difference from stock is that my mixture lever is now just a dummy since switching over to the sum carb.

on a side note: any idea what ever happened to darwin motors, up in the city? it-and he-seems to have dropped off the face of the earth.

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R11 brake plate breaking

darryl, it looks like it's no-go on posting to you...your direct email link isn't listed (just the web site), and the PM won't let me drop and paste a picture...

o.k., you can stop laughing right now, mister.

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R11 brake plate breaking

"robin748" wrote:

on a side note: any idea what ever happened to darwin motors, up in the city? it-and he-seems to have dropped off the face of the earth.

They went out of business a year or two ago. A guy I know bought their inventory, and in turn sold off everything newer than 1969. I helped him move some of it, the place was a mess. Even some customers' bikes were still there.

The story I heard was that the owner had grown bored with the shop, and moved to Hawaii where he had bigger fish to fry, so he left the manager to run things, which wasn't a recipe for success. So he closed it. I used to see their ads, but was never in the shop when it was open.

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R11 brake plate breaking

I guess if I put the correct twin slide carburetor on my R11 I will have to change from the twist grips and use the two lever set up,Is that correct? How do you use the levers? Do you open both slides the same amount ? What year was the single slide Sum first used?

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R11 brake plate breaking

sorry dan, if i made the carb question sound more complicated than it is.

first off, if you've got the correct 1930 bmw carb on it now-and it works- there's no real reason to swap it out to the twins, unless you are looking for the ease of operation-and more horsepower. but if you do decide to fiddle-and you know i have no problem with this-make sure you do it for the right reasons...like you want to! ("so it's not perfectly original for the YOM...big deal!")

first off, there's a detail problem involved: if you want to keep it %100 correct, you should know that the twin carb amal-fischer set-up was only available on R16's; the twin carbs only became stock on the R11's in the series 4 (1934).

the first year that bmw offered the side-slide sum-as a option-was 1930, but the first year that it came standard was 1931. honestly, if you're going to change things, i'd suggest the sum over the dual set-up: it's correct for the year and you can utilise the existing set-up with less fiddling with everything else.

if you do update the carbs to twins, be aware that this also involves losing the manifold and plugging the air intake from the rear of the tranny. no big deal there.

now on to the levers...:

no, you don't have to use the levers at all if you don't want to (but they are neat looking); you can use the use one of the three twist grips offered. i wouldn't worry too much about accidentally using the wrong set, as they look very similar to the average enthusiast-and most judges-but as the R16 sport version is rarer than hen's teeth, i doubt that you'll ever find one for sale-ever.

the early twist grips are for one cable only and come with a mixture lever on the top, the later ones don't. if you have one with the lever, just make up a dummy cable to look correct.

to hook up both carbs to the single cable, bmw offered a 1 into 2 splitter, but i've never seen one for sale. the closest alternative is to use their /5 version..it looks almost identical.

hope this helps...

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Throttle cable splitter

"robin748" wrote:

to hook up both carbs to the single cable, bmw offered a 1 into 2 splitter, but i've never seen one for sale. the closest alternative is to use their /5 version..it looks almost identical.

Philip Dreher offers the "one into two" splitter used on the twin carb R12.

Best regards,

Bruce

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Re: Throttle cable splitter

"frey6316" wrote:
"robin748" wrote:

to hook up both carbs to the single cable, bmw offered a 1 into 2 splitter, but i've never seen one for sale. the closest alternative is to use their /5 version..it looks almost identical.

Philip Dreher offers the "one into two" splitter used on the twin carb R12.

I'm confused (not an unusual situation!) -- At least on the R12/R17, I thought that the twin carb setup used two cables. My R12 came with twin carbs of unknown provenance. The twist grip has a hole for each of two cables, and the traveller inside is set up to capture two cable ends.

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R11 brake plate breaking

My R11 has some kind of aftermarket carburetor and I want to replace it with an original single carb and I think that would be a two slide type. I don't want to replace it with twin carburetors. I didn't realize that a side slide carb was an option. That sounds like the best set up for my single cable Amol twist grip. Does the side slide carb intake tube make a u-turn and pick the dirty air off of the cluth/flywheel area like the original two slide carb?
My rear fender flap has two bolts that attach it to the fender in about the 11:00 and 1:00 position and it sure looks original. ??

Barry Robin
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R11 brake plate breaking

naw, you're not confused there, darryl. as far as i know, all the rules change on the R12/R17.

the twin carb set up did use a dual cable twist grip-you're not going crazy...at least, not because of the thread posting.
the sum, being a single carb, has a matching single traveller twist grip; this was for the milatary model.

the twin carb was civilian and usually came with the matching throttle;for those who wished to upgrade an older bike, bmw offered the splitter so the throttle didn't have to be replaced too...

Barry Robin
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R11 brake plate breaking

weclome back, dan-i was starting to wonder what happened to you there...!

o.k., lets see...

"Does the side slide carb intake tube make a u-turn and pick the dirty air off of the cluth/flywheel area like the original two slide carb?"

-yes and no. bmw pulled their usual change the parts game the year of your bike, so either carb will fit nicely.
they discontinued the flywheel air tube the same year (because the sum has it's own external air filter); most R11s came with a blanked off flywheel cover and no tube into a slightly modified manifold , but some came with only the carb changed...go figure.

so don't change anything-just bolt on the sum carb.

on the rear fender bolts: your two bolts appear to be done in a postwar style that i'm unaware ever came on the original fender-but dont worry yet!
first make sure that the fender is correct:
all R11/16 fenders will have a single bolt holding the main and rear sections; there should be a stamped-in collar showing.
(by the way: please tell me that your fender has no hinge...; a hinged fender would indicate that the fender is from a later bike).

now, you may be looking at something i've seen before: people have modified the two small holes below meant for the taillight and moved the entire assemblly up the fender to be used to bolt both parts together. if i had a picture i could tell you instantly...
-b

Bruce Frey
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R11 brake plate breaking

"robin748" wrote:

naw, you're not confused there, darryl. as far as i know, all the rules change on the R12/R17.........the twin carb was civilian and usually came with the matching throttle;for those who wished to upgrade an older bike, bmw offered the splitter so the throttle didn't have to be replaced too...

I think that may be true for the later versions when the controls were changed to the "R5" type (retard lever and two cable throttle).

Mine is an September 1935 twin carb (with orig 20hp builders plate that matches the enine and frame numbers) with the one into two cable set up and twist grip retard. Everything else, including the scroll speedometer, seems original, so I assume the carb cabling is, too.

The Ersatzteilliste gives a multitude of different control combinations.

Best regards,

Bruce

Barry Robin
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R11 brake plate breaking

i do think you're right there, bruce; i've only seen pictures and the parts book photos, so my knowlege of the R5 setup is sketchy at best.

isn't it funny that most of us have had to become crash-course experts in all these bike details-but usually only for the bikes we've owned or had to rebuild.

-barry

holman2106
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R11 brake plate breaking

Barry, I'll try to send you some pictures of the rear fender,the fork pin striping and the center stand. It may take a few days. Thanks for all the information,I appreciate it, Dan

Barry Robin
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R11 brake plate breaking

dan-
i know this isn't quite the direction you were going in, but here's a correct series 1/series 2 carb for your R11 on german ebay:

http://cgi.ebay.de/BMW-R42-47-BMW-R11-16-52-57-62-63-Vergaser_W0QQitemZ8...

-barry

Bruce Frey
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Texas Hill Country, USA
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R11 Parts

Sorry Barry, but the only R11 brake plate I saw was already attached to another bike.

Best regards,

Bruce

Barry Robin
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R11 brake plate breaking

bruce-

ah well, it happens...but i do appreciate you looking.

so: did you find any goodies for yourself?

-barry

bmwmyplace
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Australia
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R11 brake plate breaking

Barry I see there is some concern about R11 front brake plate , are they soooo difficult to make , what about send me some close up pictures , I have a cnc maching centre....perhaps I can help....no promises though Big Grin Peter

gibbsp@bigpond.net.au

Barry Robin
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R11 brake plate breaking

hi peter-

thanks for writing to me about my little front brake problem. cnc, huh?-i never thought to do that... but it brings up a few questions:

do you think it would end up being as accurate as casting it?

one thing though: as it now has a biiig crack in it that's warped it a bit, woundn't it have to be fixed first anywayfor an correct measurement?

and it needs to be done in a composite of aluminium/magnesium; straight aluminum will be too soft. it's been fixed that way before and it ended up tearing like butter.

thoughts on the subject?
regards,
-barry

bmwmyplace
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R11 brake plate breaking

Dear Robin, ? sorry I thought it was Dan Hollman who had the problem ...anyway if one was to be made on cnc it would be more accurate than any casting...... is half a thou ok for you... Big Grin .

as for the grade of alloy there are grades available that would far exceed any casting of the 20s 30s 40 s or even todays methods, we use 7000 series alloy for suspention steering componants on race cars

No you would not have to repair it to copy it as it needs to be .drawn up first , and one can make certain assumptions to allow for distorion brakages etc

Kind Regards Peter

Barry Robin
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R11 brake plate breaking

peter-

sorry to not be peter! but being mistaken for him is just fine with me...i could do worse!

hmmm...this is sounding rather doable from your description. what would you need from me, other than the plate itself? i'm afraid i don't have the skills to put the info on disc;who much of a pain is it for you to do-and can i afford you?! Laughing

talk to you soon,
-barry

Barry Robin
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R11 brake plate breaking

peter- appropos of not much, here's a link to the bike in question:

http://vintagebmw.org/node/4770

cheers,
-b

bmwmyplace
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R11 brake plate breaking

Barry first send me some good close up photographs of the the little sucker both inside and out and see what we can see also what state are you in

Regards peter

Barry Robin
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R11 brake plate breaking

peter-
ouside is easy; inside will take a bit, as i'll first have to dissasemble the front end.
-b

EuroIron
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R11 brake plate breaking

how frail are these bikes?

they look generally robust but I'm wondering if the overall driveline would stand up to say 35 horse and a reasonably short duration 90 mph romp.... maybe more but I've no idea what final drive ratios are available for these type bikes

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