R62

[Bruce Frey]

Hello Peter,

Old motors do occassionally appear, but it may take some time.

I would advertise in the IBMWR Market


and watch eBay.de.

You might widen your search to include motors from R42, R52 or OHV motors from R47, R57 or R63. They should all fit, although the R52/57 and R62/63 are probably more correct than the R42/47.

Since the bike you purchased is largely reproduction parts (I saw the auction), you could make it any model you choose.

Good luck,

Bruce

[Bruce Frey]

I should have also mentioned that the R52/57/62/63 all shared the same frame and the same frame number series of 20000 to 30600.

Best regards,

Bruce

[1961peter]

Bruce,

Thanks for the reply.
Does this mean the engine number and frame number don't match on these models?
As you know if you saw the auction, the frame number has been clumsily changed to match the number on the R12 engine.
Unless I can find the number stamped in a second place on the frame, I will never know what the original frame number was.

Regards,

Peter.

[Hans]

Peter,

as Bruce said the bike is made of many reproduction parts. There is a chance that the frame is a repro also, so there won't be an orginal number.
These kinds of R62 (using R12 engine) have been for sale relatively frequent the last few years here in Europe. As long as you have the right tranny and an engine that fits (like an R12), the rest of the needed parts is available as repro.

Ebay.de is a possible source for finding an engine.

Greetings, Hans (Holland)

[Bruce Frey]

I am not that familiar with flat tank bikes, but I believe the only place the frame number was stamped was on the left side axel plate.....the same location where yours is stamped. The number on the R11/12 engine was altered to match R62. R12 (and I think R11, too) also have the engine number stamped in the lower crankcase casting on the driveshaft side, so you may be able to identify the motor if that number is intact.

The frame and engine numbers on these bikes do not match. The R62 engine numbers (unique to R62) are 60001-65000 and the frame numbers (shared between R52/57/62/63) are 20000-36000.

It is also possible your frame is a modern reproduction. You can make a complete flat tank bike except for engine and transmission from reproduction parts.

In any case, you have a unique machine that should be fun to play with. I would be inclined to try to get the R11/12 engine running and enjoy it until you find a more correct motor. Someone observed that the mag appears to be from a single cylinder bike, so that may be why it will not run.

Good luck,

Bruce

[1961peter]

Bruce and Hans,

Thank you for the replies.
As suggested the intention is to get the bike running, and then see if I can get the correct parts.
I understand the bike has some flaws but the reality is I could not afford a flawless bike, although I may spend as much in the end.

You note about the mag perhaps being a single one. The photos I have indicate two plug leads although the mag is not the original R62 one. The owner reports the bike starts easily but makes terrible noises when running, so an engine strip will be required.

Is there a source of information on the Bosch mags such as serial numbers for various dates of manufacture, and pictures of the various models so I know exactly what I am looking at if I find one?

Regards,

Peter.

[Bruce Frey]

I am no magneto expert, but I know the mag configuration should have the correct direction of rotation and be compatible with an opposed twin (as compared to a V twin).

The mag/generators that are listed in Motorcycles from Munich 1923 to 1969 for R11 and R12 are Bosch D2L, D2BL, D2BRS 167 and D2BRS 170. I do not know what the letters stand for.

Compatible Bosch battery ingition/generators would include the B245 RS108.

A mag from a single cylinder 4 stroke (depending on how it is driven) will probably fire every 720 degrees of crank rotation, even if it is firing both plugs. We need a spark every 360 degrees for an opposed twin.

Best regards,

Bruce

Best regards,

Bruce

[Hans]

Orginally the R62 used the D2L magnetos. Any other version of the D magneto can easily be converted to the correct D2L specification needed for the R62. From the outside you won't see the difference despite the "wrong casting" on top of the magneto. Possibly I can provide the correct D2l magneto also.

Greetings, Hans.

[1961peter]

Hans,

You indicated you may be able to help me obtain the correct magneto.

I sent you a message with my email address. Did you get this?

I would appreciate any help getting the right parts.

Regards

Peter.

[Hans]

Hello Peter,

Yes I did get your mail. My appologize for letting you wait for my answer.
I did not find to time yet to see what is available. I'll get back to you a.s.a.p.

Greetings, Hans