O U R
Being a simple screw and locknut adjustment
system, setting the clearances was quick and
easy – none of this taking the cams out and
playing with shims to get them right like on many
modern overhead cam motors. My job while this
was being done was to clean the old gasket from
the cylinder-head and rocker cover faces. We
were going to be tight on time as it was, so it was
all hands on deck.
With the valve clearances done and new gaskets
fitted to the rocker covers, attention was turned
to the ignition unit. This is commonly referred to
as the Bean Can because looks like, well, a can
of beans. This is a mechanical ignition advance/
retard that is located at the front of the motor.
When I’d told Mick about the raised idle revs
when the engine was warm, he was pretty sure
it was the Bean Can causing the issue. A lifetime
of heat causes the internals to get dry and stick
when they get hot. These aren’t a serviceable
unit according to BMW but Mick has worked
out a way to get it apart, clean it, lubricate the
internals and get it back together. If that doesn’t
fix the problem then the fix runs into hundreds
of dollars for an optical advance retard unit from
overseas. It’s something I’ll probably get done at
some point for reliability but for now I was hoping
this would fix the revving issue. Mick reset the
ignition timing once it was back together.
With fresh oil in the motor, a refreshed ignition
unit and spot-on valve clearances, the next job
was to balance the carbs. Before any balancing
was done, the carbs got a full check over to get
everything how it should be. The first issue picked
up was the inlet tube going to one of the carbs
wasn’t quite on the carb properly. I’d already
cleaned and oiled the K&N air filter before
heading to Wellington, so that was one job less
to do. After checking the float bowls for dirt, and
a new set of float bowl gaskets, the balancing
could begin.
After tweaking and tuning the carbs just so,
the idle was definitely smoother and less erratic
– sweet.
98 KIWI RIDER
B I K E S