For the correct set, check the number marked in the crankcase.

In some cases, when the engine has had a long service life, it may accept a slightly larger gear set.

F.i. a -2 marked crankcase could be fitted with a -1 gear set.

However, this can only be determined through an accurate measurement.

Distribution gears on a vintage BMW 2 cylinder motorcycle engine (youtube.com) 

The 30° gear set can be used to replace the 20° gears on all 1950 to 1963 models.

This requires following additional parts:

› part nr. 11410052156 - oilpump gear 30°

 Only for crankshaft with 17 mm taper:

› part nr. 11310010520 - 1.5 mm shim between crankshaft gear and crankshaft bearing

It's generally recommended to exchange the early 1 or 2 pin breather plates with the later model breather plate, since the pins are known for loosening or breaking off.

› part nr. 11150031171 - timed breather plate with cast in large pins

› part nr. 11310031707 - wave ring for timed breather plate

› part nr. 23211231658 - shim 1.00 mm