Numbers..

BSR is the same as the AW3, has been, .75 and 1.33

BWR is .64 and 1.57. 1:1 is the middle gear , of course..


they used a German Sachs, hub for a while in the Mk3 bikes, their first 3 by 2 _ 6 speed

.0.73 and 1.36..

Both types would have a wider driver, capable of taking 2 cogs , side by side, the Sachs adopted the standard 3 spline cog,
just made a thinner 3/32 13, & a 15t that skipped every 5th tooth as a shift gate..

The Newer hubs adopted a Shimano 9 spline driver and the cogs for those can be a 12, to 16..








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