Do keep in mind the hub date though, and the different fork crown.

-Kurt

https://www.users.globalnet.co.uk/~ha...railleurs.html

-Kurt

sure does look like it...

Agreed...a '55 drivetrain. All you need is a little help with the frame ID and you'll be set. Maybe it's earlier, maybe not. Maybe Mr Arnfried Schmitz is still around to talk?

Yeah, the Copake bike does indeed explain a few things. How far away is Copake? I'd almost be tempted to ride up there and check out that bike, maybe take some more photos.

I now I believe Zaphod's bike had a derailleur like that. But no one has convinced me, so far, that the 51 on the hub is a date; the bike may well be from that era, I don't know; I just don't believe 51 is a date.

Nor am I convinced the F&S derailleur was still made in 1955. Schmitz' article shows how rapidly derailleur technology was developing in the period 1935-1955, and by the early 50's every other derailleur system had two pulley wheels. I know Germany was ravaged by the war and all, and was never at the forefront of bicycle technology anyway, but that thing would have been a dinosaur by then. Why does Arnfried think it's a '55?

On the other hand, we know devices tend to drip to the bottom of the food chain as higher tech becomes available; Huret Alvit, Cyclo Benelux, and various other derailleurs were still OEM on cheap bikes long after better ones were available. So I suppose it's a possibility.

The key to dating Zaphod's bike, I think, will come down to components like the rims. Have you cleaned the paint off them? They look faintly like Weinmann Alesa. I'm looking forward to more photos....

On the website it appears to be stamped 1955? I agree that the technology looks older than that. The bigger question is how they determined that the Copake bike is a '38.

Yes, I see that stamping. But I don't see any reason to assume "1955" is a date. I'm not saying it isn't a date; I'm saying we don't know.

Re the "1938" at Copake: yes, good question. But it somehow seems about right, doesn't it?

Edit...

But I see on Oldbike that someone has posted a man's Presto bicycle, supposedly dated by a F&S hub stamped 37 and M, which he believes to be a 1937:


Similarly, on the same website someone has posted a German Triumph bike with a similar hub stamped 39 and M, which he believes to be a 1939:

So clearly a lot of people believe those stampings on F&S coaster brake hubs indicate the year of manufacture. Maybe they're onto something....

Here's something that may add a little credence to the date code thing

https://www.rijwiel.net/artdated.htm

(Its in German)

Heres what they say about the location of the date codes and some other stampings on the hub body.

So they're saying that if its got a Number on the Left and a Letter on the right that the hub is Pre-1958. A hub made in '58 or later would have just a Letter code, no number.


As for the derailleur, I read that Germans wanted bikes with derailleurs but also wanted coaster brakes. Sachs responded by making a Derailleur that would work with a coaster brake...perhaps the single Pulley is a necessity of design.

So what, does the pulley spindle smack the frame every time you try to brake? Or is it sprung the other way?

Well, okay then! Here's what I read at the article in your link: "According to a very interesting article about F&S coaster brake hubs in the German periodical 0 bis 100, Nr. 1/98 (later appearing as Fahrrad und Moped) the last two digits of the year of manufacture were stamped on these hubs starting around 1920."

Though your chances of picking up a F&S derailleur system are probably slim, I bet it wouldn't be that hard to fab one up... basically you'd have to attach the business end of a simple chain tensioner to a derailleur claw... friction shifter on the top tube... Interesting project!

Yeah, when you brake the chain slack moves to the top part of the chain, and the bottom part goes taught. There's a hook over the chain ring to keep the chain from falling off entirely; you can see it on the Copake bike. Obviously you'd want to have as little chain slack as possible....

That sure would be a fun project and I really might attempt it.

Here's that hook that keeps the chain from popping off the chainring

Kurt - this model is called Diana. The 1937 programme.

Does that have a front-only rod brake for the tire? I can't make it out.

-Kurt

It's a kind of rod brake; the rod presses a shoe down on top of the front tire, inside the mudguard. German engineering, you know!

spoon brake!

my thoughts exactly...just like on the old highwheelers.

my thoughts exactly...just like on the old highwheelers.

"Made in Germany" indicates pre-parting of the german state and made for export. In about the time of making (30-40´s) it would surely otherwise had a sign saying "hergestellt in Deutschland" if it was aimed at domestic market.

Very interesting thread !

I agree, however many things made in West Germany post-war were simply labelled "Made in Germany". They didn't change their name to "West Germany", they were always just "Germany". It was only East Germany who made that distinction.

I beg the difference: I still have toys for instance labelled West Germany. Also kitchenware and washing machines were labelled west. However, this bike was surely made during the nationalistic era when german language was "the law" why the sign Germany indicates some kind of export, or the World fair perhaps? Chicago some time in the 30`s?

East German products...hm, sounds nasty

Maybe we need to try and make heads or tails out of the serial numbers....I know there's at least one or two other Durkopp owners around here.

Check out this link. A 1938 German 2 gear derailleur with expanding chain. Too cool.
https://www.flickr.com/photos/collectvelo/page1/

I'm about to get down to work seriously on this bike. Gonna be starting with the Wheels, Fenders and Chainguard which are all covered in thick silver paint applied by a gorilla with a brush.

The fenders are aluminum, as is the chainguard (magnet doesn't stick) and I beleive the rims as well are otherwise I just had too weak of a magnet but i doubt thats the case.

Anyhow....whats the best way to go about cleaning up these wheels? I tried abrasives (scotch brite pad, Steel Wool, and sandpaper) with no results for a lot of sweat. I'm thinking the way to go is a gnarly chemical stripper (man that sounds like something that crawled out of a NJ swamp and went to work at Bada Bings!)

The question I really want to hear opinions on is whether I should attempt to disassemble the wheels prior to stripping them. I'm plenty comfortable with wheel building but I don't want to go disassembling the whole works unnecessarily. My concern is that If I leave the wheels built and try to clean the old paint off that I'll not get all of it off and be left with a wheel thats mostly nice clean aluminum with flecks of 50 year old paint stuck here and there.

If you want top notch results, it might be easier to disassemble the wheels. It takes a lot of time to do that and rebuild, but it's not as annoying as scrubbing around the spokes.

Not that I've ever done it that way, but I've never scrubbed away 50 year old paint from a bike. From a house, yes.