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Darryl.Richman
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As if I didn't have enough bike stuff going on right now.

I mean, I've got two complete Beamers apart in my garage. Well, sort of. The bottom end of the R12 is in Germany. And the R12 frame and the R51/3 frames are all out to The Frame Man getting straightened. (Yes, that was plural; I'm making one good frame out of two bent R51/3 frames).

So, when my friend Scott told me about an R62 drivetrain he was thinking of buying, and showed me the pictures he had, I was interested but secretly happy that he was getting it.

Then he told me he had bought it and it was being shipped. The story was that he got it from the former son-in-law of a guy who had bought the bike in 1954 to use to power a "wind boat". He had taken the drive train from the bike - the gas tank, motor, transmission and drive shaft - and thrown away the rest. I was horrified, but Scott had apparently already asked about the rest. Of course, in 1954, the bike was just a 25 year old bike that nobody wanted.



Fast forward a few weeks. Scott tells me that the boxes arrived. Then he mentions to me that he's sorry he bought the thing because he's got too much stuff and needs to unload it. He hasn't even opened the box with the motor yet. Am I still interested in it? Sigh. Of course I am. So we make the deal, and I carry home the boxes.

In one box is the gas tank. It's gray, mostly, and in pretty good shape, even including one chipped roundel. In another box is the gearbox, opened and with a bag of parts, the two heads from the motor, and the intake manifold, with an Ehrenfeld slide carburetor attached. The transmission turns, and by fitting the top with the shift lever, I can shift into all three gears and two neutrals.

The engine is a horror. None of the packing has been, what you might call, careful. But the motor was basically thrown in a box loose, with no care at all, and hardly any cushioning material. The case is cracked dramatically around the bell housing and both cylinders have big bites taken out of the outside fins, pieces of which I eventually find at the bottom of the box.



I spent about an hour doing the jigsaw puzzle, figuring out where the pieces fit in, all the while cursing the idiot son-in-law and imagining what the welding charge is going to be for this. What started out as a pretty darn good deal on the basis of a project has very quickly started to look like a mistake.


The motor itself was frozen, with the pistons at BDC and a valve on each side open. This is an annoying situation if the pistons are really stuck in the bores, because pounding on them won't really do any good and will just be beating directly on the crank.

So, I start in disassembling things to get an idea of what it's like inside. Remove the 4 cylinder base nuts on each side -- well, the 3 nuts on the right side. I wonder where the fourth went. Not all of the nuts are particularly tight, either. They're all the original style nuts, however. Oops, don't forget to remove the valve covers on top of the cylinders and remove the fifth base nut that's inside there!

Surprisingly, the cylinders both come off easily. But the crank still won't turn. I guess I have to go deeper.

I remove the 10 or 12 nuts that hold the engine cases together. I remember to remove the 24mm allen key plug on the top left side, under which is the oil pump quill shaft -- driven by a worm gear on the back end of the camshaft -- and remove it.

The cases don't want to separate easily, so I start tapping it with my plastic mallet. Slowly it comes apart.

Inside the crankshaft is revealed. Everything is covered with dried sludge. Now that I can put my hands on the flywheel, the crank will turn with a struggle. I shoot some TriFlow into the bearings and move the crank back and forth, but it doesn't loosen up.

So, I start to work removing the pistons. The pins come out with light taps on the end of a 1/4" drive ratchet extension.

While I'm working on the first one, I notice that a part of the skirt is missing, and a bit sharp. Also, both pistons are of a type that has the skirt split on one side. I've been told that these are not high quality replacements, because instead of figuring out the correct expansion, the split takes it up.

Suddenly, the crank moves freely in its bearings, and the end of my left ring finger gets caught between the sharp edge on the piston skirt and the case. Yow!! I have just grabbed a (clean) rag and am holding my hand above my head when my cell phone rings... It's in my left pants pocket... I manage to retrieve it with my right hand and flip it open... It's my wife, have I forgotten we're meeting a friend for dinner? "Well, I'm a bit tied up right now, Honey... I guess I'm going to miss it."

The bleeding slows and I finish up removing the pistons (while clenching the rag).

The crank now moves easily and smoothly. At last, there's some kind of success!

I unlodge the main bearing housings from the bottom crankcase half and lift out the crank and flywheel/clutch assembly. Actually, this looks pretty good. In fact, I can see that nobody has ever messed with this crank before! This is practically gold! Both the R12 and the R52 I've worked on had been pretty buggered up by the DPOs. (DPO stands for Darling Previous Owner.) But not only is the original crank pin visible -- because the face of the web and the pin were surfaced after assembly and the two locking pins that BMW inserted into holes drilled into the seam of the crank pin with the web are still there -- now I can also see that the crank web has the actual motor number stamped in it!!


Now, this isn't definitive, but in my excitement, I swing the connecting rods to one side of the crank, so their small end holes line up, and hold them, while trying to push and pull against them. I can't feel any movement. If that should prove to be the case once the bearings are cleaned, the crank won't have to come apart. That might balance out the cost of having all the welding done!

Here's a few more shots of the motor. Notice that the bottom case and both cylinders are stamped with the motor number. The pistons may not be original, but everything else is!







This is really great! I'm now very excited about this, but as I'm going to be out of town, I now will have to wait to do more work on the motor. I'll write more about this as I make progress.

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dunn6818
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R62 Project: The Beginning

Darryl,

Good story, I trust you'll be writing an article for the Bulletin on this ?

I know how you feel with having more than one live project & also trying to balance the priorities of rebuilding BMWs against home life & work !

My push this year is to assemble the engine & gearbox of my 1939 R61 framed, 1939 R51 engined racer & hopefully get her on the road / track.

Cheers
Peter

Darryl.Richman
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R62 Project: The Beginning

Yes, I definitely expect to get this into the Bulletin. I'm sure there will be future topics, too, like searching for a frame and forks... The Spring Veterama is this coming weekend, and I will be in Germany. But I fear I will be spending time on another project and won't be able to get to Ludwigshafen for it.

Peter, your racer sounds exciting! I know my friend Scott would be interested in seeing your project!

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Barry Robin
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R62 Project: The Beginning

darryl-

i'll keep my fingers crossed that you come accross your frame next week!

and if you just happen to find that R11 brake plate i've been looking for...i'd pay most anything you'd ask for it! might even help defray the costs of the bits you're after.

-barry robin

dunn6818
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R62 Project: The Beginning

Darryl,

My racer was the star of the "light & simple" article in the Bulletin 2 issues ago. The article is in 2 parts as I wrote up progress to Jan 05, lots more work has now been completed & I've written most of part 2.

At the moment I'm looking for carbs, I'm not prepared to pay & cannot afford the asking price for amal fischers 423s, I'm probably going to fit 274s or 276s from a Douglas. These amals are fairly common at UK autojumbles.

Cheers
Pete

Bruce Frey
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Texas Hill Country, USA
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Prewar parts

Darryl - if you can't find an original frame, Oldtimer Garage has a repop as well as a lot of other flat tank parts.

Barry - I will be at Veterama this weekend. If you can tell me what an R11 brake plate should look like (I have an R12), I will keep my eyes open.

Peter - Don't give up on the 423 carbs. I found a nearly complete pair at Mannheim last year. You probably know of Hitchcocks in the UK for the British Amal carbs. I they have 276 carbs and there is a German specialist called Kla Mo Te who often advertises the spigot mounted ones on ebay.de. While I have Amals (which I have never gotten sorted) for my R6, it actually runs better with the Bings from a R50 that came with it, so that is always an inexpensive option.

ciao,

Bruce

Ciao,

Bruce

Darryl.Richman
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R62 Project: The Beginning

Bruce, I have been looking at the Oldtimer Garage web site ever since Richard Sheckler mentioned to me on the /2 list that they have R12 wheels. I have a pair of those on order (and a pedestrian slicer for the R52).

The problem with buying a reproduction frame is that it's not vintage, with a vintage number. I'm pretty sure that California would take the view that I am building a "kit bike", and require all the modern features of a bike, like turn signals, always on headlight, front brake light switch, and so on.

But don't think I haven't considered it! Wink

The only thing I haven't seen advertised that would be necessary one way or another is a set of forks.

I wish I were going to see you this weekend -- I'm leaving for SFO in two hours -- but I think it's unrealistic to expect that I'm going to make it, alas. My R52 is in pieces and the motor has to get run in for a rally next weekend; and I will be in Denmark all week in between.

But if you do happen across a stecktank frame and/or forks...

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Barry Robin
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R62 Project: The Beginning

bruce-
thanks for asking after my R11 brake plate search; the only online picture that even sort of gets close enough for detail i could find is this one:

http://images.google.com/imgres?imgurl=http://motorcycle-web.com/bmw/r11_1929-1935/bmwR11_Zhenja.jpg&imgrefurl=http://motorcycle-web.com/bmw/r11_1929-1935/&h=446&w=646&sz=73&tbnid=Gv8r8uVFxxwQVM:&tbnh=93&tbnw=135&hl=en&start=21&prev=/images%3Fq%3Dbmw%2BR11%26start%3D20%26svnum%3D10%26hl%3Den%26lr%3D%26ie%3DUTF-8%26sa%3DN[url]

it's very similar to the R12 but it's flatter, with those ovaloid cut-ins on the face. hope this helps...
i'm just looking for one without cracks or holes.

thanks -barry[/url]

Bruce Frey
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R11 Front Brake Plate

Hi Barry,

I found some R11 pix in my photo collection. Most of them are frem past Veteramas.

Do these look right?

http://pg.photos.yahoo.com/ph/bruce_frey/album?.dir=/e000re2[url]

Best regards,

Bruce[/url]

Bruce Frey
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R11 Photos
Barry Robin
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R62 Project: The Beginning

bruce-

on the yahoo page, photo number 1 is correct; so, yup-that's the one!

on the other hand, most sellers at veterama already know which is which. just tell them it's for a series 2 or 3...

thanks,
-barry

Bruce Frey
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R11 Front Brake Plate

That is what I will look for!

I am always a little nervous when shopping for others if I am not familiar with that particular bike. There are only a few vendors that I have enough confince in to take their word for something like that.

Best regards,

Bruce

Barry Robin
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R62 Project: The Beginning

thanks, bruce.

i always thinks of the R11/R16 plate as being just like an R12-just flatter.

if you do find one i can always send you the money via paypal; no reason for you to not have the ready cash for yourself (damn-i can't buy that left-handed nose inhaler with the bmw logo, now that i've spent my money on this stupid plate!)
take me away, calgon!

-barry

Peter D. Nettesheim
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R62 Project

DSR,
A little info. First, the split piston does not have the split as an inexpensive way to compensate for expansion. New pistons are what is known as "cam ground" In other words the piston is not round. It is wider perpendicular to the wrist pin. The narrower portion is manufactured this way to permit expansion in this axis.
The earlier split pistons were not cam ground. They were round. The only way to permit a round piston to expand is to put this cut into it. That is why it is there and that is an old piston.
As far as the engine never being apart, I'm not so sure on this one as from one of the pictures I see you are missing internal engine parts. In particular the cover for the front main bearing behind the removable breather gear insert. The oil flow in this engine is a bit tricky to understand and you are missing one of the main parts.
That engine will require line boring to assure proper crank bearing alignment.
You have got some work ahead of you. Good luck.
Peter D. Nettesheim

Darryl.Richman
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R62 Project: The Beginning

Peter, thanks very much for the reply! I guess I am going to need some information regarding the way that the bearing is supposed to be set up. The parts book only shows the entire bearing and and body as one piece, as a side view, and doesn't elaborate about what's inside.

Regarding the pistons, I must admit that I am just repeating what I was told by what I thought was a reliable source. I understand about pistons not being completely round to take up the uneven expansion due to the strengthening for the wrist pin.

But neither do these pistons seem to be original. The parts book clearly shows the originals have 4 rings, with one oil scraper below the wrist pin. These are 3 ring pistons.

In your experience, do you think that the cases absolutely will require line boring? I guess I would have preassebmled the case halves and then checked for runout, the way one does on a /2 or /3 motor.

If you can assist me with more information here, I'd really appreciate it!

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Peter D. Nettesheim
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R62 motor

DSR,
There is a lot of things to look at with this engine. I hate to admit it but I learned quite a bit from various mistakes I have made when rebuilding these(R32,52,62,63,57,12,11), and they are all very similar engines.
First, I dont think you will really have to line bore it. Think of the dificulty of doing this job. First you would end up cutting off the oil feed ports on the bottom half of the engine case that also act as locating pins for the bearing retainers. Then you would have to replace them and make larger bearing retainers to fit. Its not practical.
I started thinking of all the items to watch out for such as:
1)Watching out how tight to make the bolt that holds the front cam bearing in,
2)Confirming the main bearings are tight in the bronze bearing retainers and then in the case,
3)Measuring clearance for the front breather cap that surronds the breather ring on the front of the crank
4)Confirming that there is proper oil flow to the front gear set
and so on and on and on.
I have seen mistakes on each and every one of the above items that ended up causing complete engine failure. Fortunatly I learned before I rebuilt mine.
As I said..good luck, I'll try and help where I can but you are starting with something that looks rough.
Peter D. Nettesheim

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more r62 stuff

OK DSR,
I am now going to give you a few questions. The purpose of the questions will not be to test your knowledge but to get you to think about why certain things in that engine were done the way they were.
1) Why does the engine case casting surrond the flywheel? This make no sense to the untrained eye as it requires the engine case to be split to do a clutch job. Why did they do this and why were they able to avoid this in the next series of engines (eg R12)?
2) Why is the little bolt on the right side of the engine the only one that is wire tied?
3)Explain how to time the magnito.

Get these right and you win...................three more questions.
good luck
Peter D. Nettesheim

Darryl.Richman
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R62 Project: The Beginning

Peter, thanks again for sharing your insights. I'm very interested in your questions...

1) I have no idea, but exactly what you're saying has occured to me. As I learned in the R11 thread, early on in that model they changed away from the two slide BMW carb, which mounts to the back of the bell housing and uses an openning there for it's filtered air intake. (BTW, if you understand why pulling the air from around the clutch is considered some kind of filter, or even what the rationale here is, I would love to know.) Anyway, this detail is the only thing I can think of that might be relevant, and yet I cannot see how. So, definitely count me amont the untrained!

2) That bolt locks the front cam shaft bearing housing in place, and so it, along with a few other bolts that, were they to come loose, might be particularly dangerous, were safety wired. (The bolts holding the driving dogs flange to the crown wheel in the final drive, and the screws that hold the windage plate over the sump, are others I can think of.)

But that does bring up a question for me: once the bolt is removed, what is the secret to removing the cam? There's a blind bushing at the back, but I don't want to beat on it with a drift. There's no obvious puller location provided in front. Is heat my friend here?

3) I have read the owner's manual a number of times, but I can't quote it verbatim. Basically, the crank is placed into the crankcase with the pistons set to OT. The cam is set so that it's driven gear has the two adjacent teeth with marks surrounding the intermediate gear's marked tooth. Only then can the cases be joined, and the cylinders installed. From here, the motor is set to -- I forget the exact number, but it's about 9mm -- before OT on the #1 (right) cylinder. One actually backs up the motor and then brings it to this point in the forward direction so as to take up all the lash. Now, the magneto is set to just breaking for the #1 cylinder, and installed.

If nothing moves while doing all this, then the motor has just been timed for full advance.

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Peter D. Nettesheim
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R62 Project: The Beginning

Ahhhhh!
Now we are getting somewhere! I'll start from the beginning and give you the explainations. Your answers show you are thinking but you missed a couple of key things. First to question number 1
1) The rear of the engine is enclosed as doing so substantially increases its strength in that area. In particular around the rear bearing retainer which is under pressure to flex. It is the same reason that an angle iron has more strength than a flat piece of steel. The metalurgy of the time was not the best and they needed to form the back of the case in this way to add strength. As the casting processes advanced together with the quality of the metals this very non service friendly casting was dispensed with. What I liked in your answer is that you picked up on the whole flywheel intake thing. Here's the answer to that question:
Air filtration was primitive at the time. The engineers needed to design an intake system that could supply dry clean air. How to do this? Increase the length of the intake tract giving more time for dirty particles to drop out of the incoming air. Look right from the start of where the air enters the engine. Where is it? It is behind the cylinder where it is protected from a water splash, pre heated upon intake and far from the intake valve. It then has to circumvent the spinning flywheel which acts as a centrifical cleaner before it enters and then doubles back through the carb and down the long intake tubes. Its much cleaner by time it gets there.
Now to answer question 2:
2)I have to say that you almost got this one but you missed the critical issue. The bolt is not wire tied as to protect a dangerous or catastrophic failure if the bearing it holds would come loose. You are using the typical reason bolts are wire tied and it does not apply to this small bolt. Why would you need to wire tie a bolt in place? In this case its because you cannot tighten it to the torque a bolt of this size would normally have. Why? Because, if you did you would radially load the cam bearing, distort it and cause its failure. Understand? So now you have to leave it a bit loose, only tight enough to hold the bearing in place but not tight enough where it will stay in place. How to prevent it from walking out? Wire tie it!
As far as removing the cam, you need the correct tools.
Now to number three.......
3)You are really close on this one too but I don't like the whole crank placement issue as this is not pertinent to the task. What if you needed to replace a weak magneto? Would you have to re lay the crank?No.
The process is basically as you said but you need to get rid of the extraineous info to understand the real process. Set the mag at full advance. Turn it until the points just break. Check which side is firing (this is not like a R60 where both plugs fire at once!) You do this by removing the ignition wire at the mag and confirm the 6mm brasss strip on the bakelite rotor is facing the cylinder you intend to time. Set the piston at top dead center and then turn backwards about 10mm (this is different for the touring and sport models) of piston travel. Install the mag. Done.
Well I give you a B+. Most people don't even understand the questions.
I will tell you there is no less than 100 such questions that all need to be understood to have one of these engines run properly. Are you ready for the next three questions?
Peter D. Nettesheim

Darryl.Richman
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R62 Project: The Beginning

So, did the casting technology get that much better in the 6 years to the R12 that they could do away with the enclosed bell housing? Or did they find another way to reinforce the rear bearing carrier?

The intake still seems so odd. On later bikes they just took the expedient of pointing the intake backwards. Even when they were selling the M2B15 to other manufacturers, it seemed that this was the standard approach. Victoria, for example, had a short tube, pointed backwards, that openned near the trailing cylinder finning.

Regarding the cam housing bolt, this is similar to the vent bolt BMW began using on the /2s and continued through the Airheads, to lock the speedometer cable to the transmission. That bolt should never be torqued to the standard level that such a bolt is capable of; it will likely strip out the transmission case.

Anyway, what tools do I need to remove (and replace) the camshaft?

As far as Q3 goes, I was just trying for extra credit on the question I understood. Wink If one splits the cases, then one must set up the crank/cam timing first, then go on to the mag timing. I will have the pleasure of getting this right on my R12, when I get back from Germany in a few weeks. The R12 is, to my abilities, much more finicky because of the care and close work necessary to put the timing chain together without dropping small parts into the motor...

Well, if you're giving me a passing grade here, I'm eager for the next test! Wink

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Peter D. Nettesheim
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Lets talk magneto's

D,
Just a few quick but no so easy ones
1) Do you have a mag for the r62? The proper one is a Bosch "D" Zunder. The R12 uses the same model but you can't take a magnito from an R12 and use it with the R62. Why? I'm not talking about the chain vs. gear issue. What is the major difference and by looking at the mag (assuming it has no gear or sprocket), how can you tell which one you have?
2)Explain why, unlike a R60, the bosch "D" Zunder only fires one side at a time. Explain why a R60 fires both.
3)Lets say the generator portion of the "D" Zunder isn't charging (count on this one once in a while!). You take it off the bike to check it. How, on the bench, can you determine confidently if its the regulator or perhaps an internal problem with the generator windings or brushes?
Good luck! I expect no less than an A+ grade on this quiz.
Regards,
Peter D. Nettesheim

Darryl.Richman
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R62 Project: The Beginning

1) I don't have the magneto for the R62. But the R12 takes a D2B and the earlier bikes take a D2A. The difference is the direction the input shaft rotates, because the chain drive preserves the direction of the camshaft while the gear setup reverses it. The direction is indicated by the arrow stamped in the case

2) All of the postwar magneto bikes have a "wasted spark" system that fires both plugs on every crank revolution, even though the points are mounted on the end of the camshaft, because the points cam has two lobes. The difference in how they wear is what causes the frequently experienced differential timing on those bikes.

The magnetos on the split case motors fire only once every camshaft revolution (half crank speed) and a rotor inside the magneto with a small metal strip on the edge determines whether it will be the left or the right cylinder that fires.

3) I don't really know. But I would suppose you could put it in a vise and chuck up the input shaft in a drill motor, and then start probing with the VOM. I would suppose that one could follow the trouble shooting directions in the back of the 4-language /2 factory service book, since the regulator looks pretty similar.

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Peter D. Nettesheim
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R62 quiz

D,
1)You are right on the money. The gear driven magneto is referred to as a "left turn" magneto while the chain driven is a "right turn". You can not interchange the two but a rebuilder can make a left into a right and vise versa if the buyer so requires. As you said the direction is stamped in the case on a removable plate.
On question 2 the number of revolutions is not really the issue. Let me pose the question this way: Why does the "D" zunder have that distributor strip? Why not just eliminate it and fire both plugs at the same time?. The magneto would be simpler to manufacture. The number of revolutions of the engine or cam does not change the fact that with that one set of points you could send a charge to both plugs at the same time.
The reason that the magneto only fires one side at a time with no wasted spark..........................the magneto is just not strong enough to reliably fire both plugs at once. Its four times the size of an R60 magneto but the older technology of this unit made it weaker than a modern unit. Simple.
Now to three..............
This is a bit difficult to explain over the keyboard. Like any analysis of a problem, the better you can isolate the indivdual components the easier it will be to determine the problem component. With the magneto on a bench, you can check the field, windings, brushes and other components by turning the generator into a motor. This is done by removing the regulator placing 6 volts pos to the pos brush and grounding the case (do not ground the other brush!). If the components are in good shape it will turn like a starter motor, just a lot slower. Then you need to look at the regulator which I have found to be a regular pain. Put the electronic one in and forget it.
Thanks for taking the time and when you run into that real bitchy problem.....drop me a note. Maybe I can help. When and if you want some more questions let me know too.
OK just one more..........and this is an important one to anyone rebuilding a R32 or R42 out there.
Tell me the difference in the transmission lubrication system between an R32/R42 transmission and a R52/ R62 transmission? Not knowing this screwed me up with a project for years...............
Peter D. Nettesheim

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R62 Project: The Beginning

Oh! Oh! Oh! Pick me! Pick me! Wink

This little thing is mentioned in a by the way manner in Slabon and Knittel's Buyer's Guide, and it stuck in my head. The earlier transmissions were filled with grease rather than oil.

And the reason that stuck in my head is that when I took my R52 apart, I found that the final drive was grease filled. However, in my case, that was done because the final drive case was in such poor shape that it wouldn't hold oil any more. It was cracked and broken and had already been rewelded on both mounting flanges. Fortunately, both the ring and pinion gears and the "mitnehmerflansch" were all in good shape, and Dreher has new castings that work great -- and for the price, they should!

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Barry Robin
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R62 Project: The Beginning

sorry to butt in...

i'm quite enjoing this catechism question and answer thread-thanks to both of you; besides learning a lot of usefull information, it's nice to know that the factory did things a certain way that helps to put in context all the eye-opening internal oddities that i dealt with on the R11-so i'm not alone!

and i thought i'd throw in a tidbit on my R11 tranny: because my bike sat undisturbed for all those years in the garage, i found what i may assume is close to the original grease in the tranny case...yuck! semi-solid sludge that only loosend up with a blowtorch and a chisel...

sorry to interupt; we now return to our regularly scheduled program.

-barry robin

Peter D. Nettesheim
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hehhhh!!

D, Who's this robin guy???? He sounds like he may know something. I'm going to have to reserve some of the tougher questions for him.
First, yes, you finally get the A+. The r32 and 42 transmissions were greese transmissions. Do you have any idea how hard it is to prevent thin oil from leaking out of a transmission that was designed to hold greese?
Next question:
Explain the use of blue and white in the BMW emblem.... and don't give me any of that propeller in the blue sky crap. No the white doesn't represent the clouds either. There is a very appropriate that the colors are blue and white. Why?
Peter D. Nettesheim
P.S. I would like to get some answers from someone else too. Come on, all chime in now!

Peter D. Nettesheim
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more modern stuff

D,
I have found that being of German decent and being enrolled in an engineering school for a few years may just somehow help me better understand the design of the BMW products. I don't quite fully understand it, but when I work on these bikes things just make sense. I once had to work on a french car and nothing made sense. It was not my lack of experience with the product its just that on everything I touched I found myself asking "why would you make it like this and why would you put it together like that?
So I have to once again open the can of worms and say that "a slinger is in no way a filter". Can you explain why? Can you bring forth a reasonable argument as to why this cannot possibly be a filter? Do you even agree? This statement does not change the fact that it collects debris and needs to be cleaned but I can confidently say that at this point , after years working with the early engines and seeing how the slinger in the later bikes came to be, that it is not a filter and that this device was never intended as a filter. To help my argument, I will at this time only say "what is the purpose of a filter and what does a good filter help to prevent?"
Anyone else have something to say? and please tell me you know exactly what the slinger is before you answer..........
P.Nettesheim

Darryl.Richman
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Re: hehhhh!!

"Peter D. Nettesheim" wrote:

D, Who's this robin guy???? He sounds like he may know something. I'm going to have to reserve some of the tougher questions for him.

Good, because now that I've got my A+, I feel like I should quit while I'm ahead. Wink

Quote:

Next question:
Explain the use of blue and white in the BMW emblem.... and don't give me any of that propeller in the blue sky crap. No the white doesn't represent the clouds either. There is a very appropriate that the colors are blue and white. Why?

Rather than give another partial answer, I would point folks to the article on the subject that was in one of last year's editions of the BMW Mobile Tradition magazine. (I will have to hunt up the exact issue, but they're all available for free at the BMW MT site.) The basic answer is that the circular design came from the Karl Rapp logo (circle with a black knight chess piece) and the colors of the Bavarian wappen (heraldic shield) in a design that was close, but didn't actually infringe, upon the Bavarian state's design.

Here's one back at you, Peter: what are those Bavarian colors and wappen design supposed to represent? For extra credit, how do the Bavarians always refer to them?

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Darryl.Richman
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Mobile Tradition Web Site

If you have some patience, you can hunt around the BMW AG web site and find the Mobile Tradition area. However, until they change the site again, you can use this link to it.

The article I was referring to is in the 2005 issue 1 of the BMW Mobile Tradition Live magazine. You can go to this page and download the pdf file. The article is titled "Fact and Fiction" on pages 38-41. The article begins:

Quote:

The origin of the
BMW logo –
fact and fiction

There are two traditions concerning the significance of the BMW company logo and
trademark, offering two different interpretations of the blue and white fields in the
logo. One interpretation points to a link with a rotating propeller. The other relates to
Bavaria as the place where the products are manufactured. A closer look at the available
sources and the historical background reveals one account as a myth while the
other emerges as a historically plausible explanation.

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Peter D. Nettesheim
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r62 and more

Ok,
I guess you have more info on this one than me and I can't answer the one about how the bavarian's refer to the colors (blau mit weiss?)So we will leave it at that. Plus I'm the one who's suppose to be asking the questions anyway.................... Now I'm going to have to find a real bitch of a question to ask. Let see, humm.......how about the meaning of the "S" on the end of the original DM 175 T1S spark plugs for the R17....... How about what the "D" means on the same part?......
Peter D. Nettesheim

Darryl.Richman
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R62 Project: The Beginning

Bavarians always refer to the "lozenge" flag, and Bavarian colors as weiss-blau, or weiss und blau -- that is to say, white-blue or white and blue. Never the other way around. (If you look at the Bavarian state web page, you'll see that they do follow this principle.

The white-blue is supposed to represent the sky in Bavaria. If you follow the link above, you'll find this line in the Bavarian anthem:

erhalte dir die Farben seines Himmels weiß und blau!
"Keep your heavens' colors of white and blue!"

So now you know! Wink

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bmwmyplace
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Re: r62 and more

[quote="
Ianyway.................... Now I'm going to have to find a real bitch of a question to ask. Let see, humm.......how about the meaning of the "S" on the end of the original DM 175 T1S spark plugs for the R17....... How about what the "D" means on the same part?......
Peter D. Nettesheim

Hey Peter as I have an R17 I am most interested in the answer, or was it anwsered somewhere else Regards Peter G

schrader7032
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San Antonio, TX
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R62 Project: The Beginning

I searched the forum for "DM 175" and came up with these posts...

http://vintagebmw.org/forums/viewtopic.php?t=121&highlight=175

Kurt in S.A.

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bmwmyplace
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R62 Project: The Beginning

Thanks Kurt thats great ...Peter

pierce7221
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VT, USA
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Re: R62 Project: The Beginning

"Darryl.Richman" wrote:

Both the R12 and the R52 I've worked on had been pretty buggered up by the DPOs. (DPO stands for Darling Previous Owner.)

wowie. i thought i had trouble with my R50's DPO (made a thread on another forum just to complain about him), but it's nothing compared to this. i've always loved the style of those ancient models with the gas tank on the inside of the frame. good luck Cool

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