Page E2
May
1936
NEWNES PRACTICAL
MECHANICS
443
Drawings for
these various bolts are given, as well as for the engine plates. These are made from
3/16in. mild steel, and the photographs show their location. It will be seen that one long
transverse rod passes through the, front engine plate, and others behind the engine and
behind the gearbox. The engine and gearbox sprockets are aligned and located by means of
pieces of steel tubing which pass over the bolts, washers also being placed at each end,
where they abut with the main wooden chassis members. The washers will prevent the tubes
from biting into the wood and permitting movement.
A Matter of Alignment
It will be appreciated that the driving sprocket on the engine shaft must be in exact
alignment with the inner gearbox, and that the outer sprocket on the latter must align
with the gear wheel on the rear wheel. The distance pieces (tubes) on the engine bolts
securing the engine to the chassis should be cut so that this alignment is secured. I
stress this point because if the alignment is out the chains will run off. The gearbox, it
will be seen, has two short studs in the top of it, and these pass through a piece of
3/16in. mild steel with long holes (to permit of front chain adjustment as with a
motor-cycle) and which bridges the two gearbox plates. By locking the nuts after the chain
tension has been adjusted (the chain should be allowed to sag for at least 1/2 in.), this
plate will also secure the gearbox.
Long Bolts, Distance Pieces, etc.
Notice the position of the long bolts, distance pieces, and washers which secure the rear
suspension, and observe also that two plates pass outside the body at the point where the
rear engine plate meets the gearbox cradle plate. This is a somewhat lengthy description
of what is in reality a straightforward piece of metal working. If you have not the dies
and screwing tackle, 1 can let you have the address of an advertiser who will be able to
supply you with the parts already out to shape and length.
Last month I gave one method of anchoring the rear wheels to the rear forks.