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Cyclemotor spares
by Brian Smith
The hobby of "clip on" restoration, by which I mean perhaps
the major activity, is still a relatively cheap and easy one for
the DIY man. Except for rare models it is still mostly a
home job combined with many visits to autojumbles. The fact
that most of these "clip on" engines were bought as separate
entities from the cycle and mounted on a 1940s or 1950s bicycle
made most installations different from one another. From
quite early days purchasers became unhappy with some aspect or
other of a particular model and modified the original to what
they thought was a better system. Magazines such as "Power
and Pedal" carried frequent articles on such topics as: "How I
converted my Mini-Motor to chain drive" or "The £10
moped" (How to mount a Cyclemaster engine externally to the
wheel).
It is against this background that I would argue to try and
keep the hobby a relatively cheap one in which to indulge.
I would further suggest that in very many cases more satisfaction
falls to the restorer by adapting parts himself than by
purchasing replicas. I do realise that this will not apply
in all cases and that many restorers have no engineering
knowledge or equipment. It has certainly been my practice
to use what I misquote as "Restorer's Licence" to make and adapt
wherever possible. I have now completed 28 models and have
three more in the pipeline. All are on cycles and most can
be jumped on and ridden. They frequently are - not many
days pass when I do not go for a spin.
Some of the parts I have made are more true replicas than
others. Some are better functionally than the
originals. All enable me to get the bike on the road at
very low cost, on the whole. Examples are taken from back
numbers of "Buzzing" and talking to other enthusiasts about what
is usually missing. I give some examples with a brief
comment on how to replace the item:
- Cyclemaster exhaust - Electrical conduit bent by local
electrician.
- Mini-Motor hoop frame - ditto; the mechanism for lifting on
and off the wheel is converted to Mark I standard which, although
not as positive, works and is easy to make. Use the clutch
lever off a scrap motorbike for a good pull at the handlebar - it
is easy to make a click-in notch.
- Ducati Cucciolo pedal cranks can be made from standard pedal
cranks but require some turning facility.
- Carburettors for various models. These are very
adaptable. May I suggest a few extra alternatives?
Chain saws are available in a truly amazing variety of
sizes. The carbs are usually diaphragm type and so are not
easily adapted in toto; jets, however, are.
Carburettors which are easy to find at autojumbles are the ones
off Cyclemasters and Mini-Motors. These cover 25cc, 32cc
and 49cc engines. Adapt to your motor with a jet from a
chain saw stockist. Carb modifications from other mopeds,
all readily available from scrap-yards, are endless. They
are, however, almost certainly for 50cc engines, so if you use
one on your under-50cc motor you will have to "jet down".
- BSA Winged Wheel petrol tanks - Visit your local scrap yard
and look out for a Honda 50cc Graduate moped of the 1970's
vintage. You will have to saw the tank off the saddle
pillar but thereafter, with a bit of mechanical (NOT welding)
adaption it is very simple. The tank is also very similar
to that used on some versions of the Mosquito. This moped
is also a good source of ignition coils for the Vincent
Firefly. The carb is similar to a Power Pak's but the swan
neck will need adaptation.
- Cyclemaster covers for the carb are much easier to make in
either aluminium or copper, as it is easier to cut (use your
wife's scissors when she is not looking). Shape with a
ball-ended hammer on a bag of sand. When painted, who knows
the difference? Look on your tip for an old washing machine
as the cover is usually aluminium. For copper use a hot
water cylinder or a piece from the scrap dealer.
- Cyclaid wheel drive pulley - washing machine?
The list is endless
Finally, I must emphasise that I am not offering a
perfectionist's solution for a concours competition but rather
a practical engineer's approach to the keeping-going of the fun
of maintaining motorised bikes.
First published - May 1991
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