what ratio is correct for the drive shaft out put

so the output splined receiver needs to be replaced.
my bike is a 1971 R75/5

I went onto the parts diagrams... and see they sell 2 different ratio's
they call it the "clutch bell housing" part number 6

which ratio is correct for my bike?

thanks in advance.... looks like there is one at 1.6, the other at 1.7 with different part numbers

brant

Not sure what the 1.6 and 1.7 means...I forgot what the "Supp" column is for. But you want the shaft number that ends in 972. Your bike is a short wheel base and was used up to some point in 1973. Notice on that one the end date of 19730200, suggesting used up to February 1973.

I'll have to think about the clutch bell housing. Maybe since the shaft number for the SWB bike is Supp = 1.7, you want the bell housing for 1.7?

I think I can reuse my actual shaft
and just replace the #6 cup.... (bell housing)

so the 1.7 because it matches the shaft (for swb) which is also a 1.7 ?

thank you again Kurt...

I'm not really sure. I think "Supp" refers to a supplement of some sort...when they had parts listings on fiche or something called the Snabb catalog and the supplement referred you to a companion booklet. If you were to order the part from say, MaxBMW, they might have a knowledgeable enough parts person to figure it out. Certainly a Mr. Tom Cutter or Anton Largiader might be able to figure out what you need as well.

Update: Didn't find out what "Supp" refers to but found this on Snowbum's website which helps explain other entries:

https://bmwmotorcycletech.info/partsymbols.htm

Supplement is just extra information. Like, for example the size of a bolt.