SWB is Short Wheel Base, LWB is Long Wheel Base
The question keeps coming up "What is this long wheel base and how do I know
if I have one?" A very good question and the answer is simple. When BMW came out
with the /5 series in 1970, the bike had some stability problems. See my
page on wobbles for more info on this subject. In
the middle of 1973 production, BMW started using a longer swing arm to get more
wheelbase and therefore more stability. It worked. If you inspect the swing arm
(drive shaft housing) you can see what you have. The difference isn't
This rough sketch shows three types of swing arm used on the bikes. The upper
one is a SWB from 1970 to mid 73. The middle one shows a piece that is "welded
in" to make it longer. The text is in error, the 74 had the weld and
it was 75 and on that was "finished." The bottom is a "finished" LWB swing arm.
A SWB swing arm
A mid 73 LWB with the welded in 2" piece.
The 75 and later type LWB.
The result of the longer swing arm is a BMW motorcycle that is far more
stable. One could load it up with more junk and still not wobble. The price paid
is much slower handling. The SWB is better for solo sport riding. The LWB is
better for two up touring with luggage. It is certainly possible for
the LWB to wobble, but is less likely.