Because the K bike engine lies
flat with the cylinder head to the left, oil can seep past
the piston rings into the combustion chamber when the bike
isn't running. This is especially true if the bike has been
left on the side stand with the cylinders angled downward.
This can create a lot of smoke when starting and is nothing
to worry about. Just ride the bike to burn off the extra oil
and the smoke will go away.
In order to somewhat mitigate
this problem, BMW upgraded the piston rings in June of 1988
so K bikes with a model year of 1988 or earlier will tend to
smoke more on starting.
However, any year K bike, if left
on the side stand long enough, will have some oil seep into
the combustion chamber and be smoky when started.
If you're bringing a K bike back
to life after sitting for several years it can generate
quite a bit of smoke. This can take several minutes to
burn off but is nothing to worry about.
There's really nothing you can do
to prevent this from happening but there are a couple of
things you can do to lessen the amount of oil that seeps
past the rings:
1) Use the center stand.
Since the engine remains flat, not leaning to the left, less
oil will seep past the rings.
the bike to the right after turning
it off. Turn the bike off and tilt it to
the right for 10 seconds or so before putting it on the side
stand. This allows much of the warm oil behind the cylinders
to drain back into the oil sump, leaving less to seep past
© 2018 Drake Smith - Please do
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