Early pre /2 “sports” gearing?

[808Airhead]

I was reading my vintage, original print 1958-59 factory repair manual, which came with my 1958 R69, and interestingly I saw this about the “S” stamp which I always read stood for “Solo” vs. “sidecar” gearing. But here it is listed as a ”sports” option with completely different 1-3 gear ratios. It lists it as a “option” for R69 as well, which may be a mis-print(?). Either way, the /2 bikes supposedly all came with a “S” transmission unless you opted for sidecar gears….SO, the big question is…… when did the “S” change from “sports” with different ratios, to “solo” being the same gearing throughout the range? My R69 has a “S” transmission which I believe to be original to the bike since it has the early pawl spring transmission and the clutch arm pivot pin hole was worn thoroughly exhibiting old age / use, so that is a bonus (?) Anybody have an idea about this?

[caker]

This could be revisionist, but from this July 1968 service bulletin, it implies it (was always):

• Sport transmission was for solo bikes
• Standard transmission was for sidecar work

Further distinguishing mark of the two transmission executions constitutes the letter "S" stamped onto the sports transmission, close to the oil intake plug. The standard transmission is not marked.

And Huggett lists these part numbers for all the "/2" bikes (1955-1969)

• 23 00 1 000 028 Gearbox
• 23 00 1 000 035 Gearbox ( Sport )

And this one but only for R50/2 and R60/2

• 23 00 1 000 026 Gearbox ( SW/Sidecar )

He also lists that one as for sale, but "not a stock item" so maybe it's a one-off or a service he provides, and should be discounted for purpose of your question

:shrug:

-Chris

[niall4473]

The wide-ratio gearbox was standard, close-ratio was an option.
Although the wide ratio box is nowadays though of as purely for sidecar work, it was not always so.
Our friends in North America may not be aware of just what a high proportion of BMWs were sold to fleet buyers, particularly pre-1960, many Police forces, military, postal, forestry, railways, roadside assistance organisations, etc. in Western Europe, South America, South Africa etc., bought large numbers of BMWs and for some of them, being able to ride, clutch home at a marching pace was absolutely essential, the Triumph 6T Thunderbird, another popular fleet bike, also had to have this ability.
Only after the financial crisis of 1959-60 did BMW start to try to sell their bikes to private buyers, rather than just making them available to purchase, and to actually develop the US market which the British manufacturers had opened up, this also coincided with a massive decline in the number of sidecar outfits in use as domestic and commercial transport in Europe, hence the previously truly optional sports gearbox became the de facto standard, in all but name.

[808Airhead]

Thank you! That puts a different perspective on the question at at hand. That makes total sense, I never knew or would think that these bikes would come with sidecar gearing as “standard”. So basically, the standard equipment became the “S” gearbox ….basically just solo gears, same ratio as pre /2. So there are not any “special” sports gear ratio I guess.

[Seek]

Have a look here: http://www.beemergarage.com/sales_brochures.html

In 1957 al the bikes came with the standard gear ratios. That is 1st gear 5.33:1.
In 1958 all the bikes came with the sport gear rattios. 1st gear is 4.17:1