Since
there was a good going storm here yesterday I decided to tidy up my
study. In the course of which I found a sketch I’d made many years
ago.
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| Lots of washers! |
This
is the contact breakers on my first bike – Yamaha CS5E 200cc two
stroke twin. So I would have made the sketch in 1975.
Those
of you younger than late middle age may not know what contact
breakers are. And for that you should be thankful. Contact breakers
were part of the ignition system. They switch the power to the
ignition coil on and off as the engine turns. This causes the coil to
produce a high voltage that provides the spark that ignites the fuel.
Contact
breakers required maintenance. Wear in the fibre follower means that
the ignition timing can go out and make the bike badly. In addition,
because there is sometimes a spark as the point separate, the faces
of the contact surfaces can become pitted. Replacement points should
then be fitted.
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A contact breaker. The fibre follower is at the bottom and the points on the left
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Back
in the day points for Japanese bikes were expensive. Unlike cars
bikes did not use distributors so there were a set of points for each
cylinder. What I guess I was doing when I made the sketch was taking
the breaker assembly apart to file the points smooth.
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Points on a Suzuki GT750 - one set for each of three cylinders. Much fun adjusting these
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By
the late 1970’s points had been replaced with electronic ignition
which requires no maintenance.
