Cross Reference Index for Rear Drive and Speedometer Ratio - Speedometer ratios as found on the bottoms of the speedometer housings
The following is a listing of the available Rear Drive Ratios and the Speedometer ratio which applies to that specific ratio. The speedometer ratio is the small two or three digit number found on the face of the speedometer near the bottom of the speedometer housing.
Interpolating the ratio in miles for the /2 series can be obtained by comparison with the pre-1960 models.
For example: The R50 solo in km is W=0,75, which is the same for the R50/2. The R50 solo in miles is W=1,2.
Pre-war parts manuals show the speedometers cross referenced with the final drive ratios and their corresponding part numbers, but not the ratios stamped on the bottoms of the speedometer cans.
This information courtesy of Stephen Ascheral.
| R51/2 solo 35:9 in km | W=0,95 |
| R51/2 solo 35:9 in miles | W=1,52 |
| R51/2 S/W 32:7 in km | W=1,15 |
| R51/2 S/W 32:7 in miles | W=1,84 |
| R51/3 solo 35:9 in km | W=0,95 |
| R51/3 solo 35:9 in miles | W=1,52 |
| R51/3 S/W 32:7 in km | W=1,15 |
| R51/3 S/W 32:7 in miles | W=0,84 |
| R67/2 & /3 solo 32:9 in km | W=0,9 |
| R67/2 & /3 solo 32:9 in miles | W=1,44 |
| R67/2 & /3 S/W 35:8 in km | W=1,1 |
| R67/2 & /3 S/W 35:8 in miles | W=1,76 |
| R68 solo 35:9 in km | W=0,95 |
| R68 solo 35:9 in miles | W=1,52 |
| R68 S/W 32:7 in km | W=1,15 |
| R68 S/W 32:7 in miles | W=1,84 |
| R25/3 solo in km | W=1,0 |
| R25/3 solo in miles | W=1,6 |
| R25/3 S/W in km | W=1,15 |
| R25/3 S/W in miles | W=1,84 |
| R50 solo in km | W=1,75 |
| R50 solo in miles | W=1,2 |
| R50 S/W in km | W=1,0 |
| R50 S/W in miles | W=1,6 |
| R60 solo in km | W=0,7 |
| R60 solo in miles | W=1,12 |
| R60 S/W in km | W=0,9 |
| R60 S/W in miles | W=1,44 |
| R69 solo in km | W=0,75 |
| R69 solo in miles | W=1,2 |
| R69 S/W in km | W=1,0 |
| R69 S/W in miles | W=1,6 |
| R50/2 & R60/2 solo in km | W=0,75 |
| R50/2 & R60/2 solo in miles | W=unknown |
| R50/2 & R60/2 S/W in km | W=unknown |
| R50/2 & R60/2 S/W in miles | W=unknown |
| R50S solo in km | W=0,86 |
| R69S solo in km | W=0,75 |
| R26 & R27 solo in km | W=1,0 (also: W=1,08 without indication for sidecar use) |
| R26 & R27 solo km | W=1,0 |
