SC
OOTERING
PRA
CTICAL
seriesof splines and usesapinch bolt to
secure it. This needs to be fully tightened,
but it is difficult to gain access to it.
Because it can come loose easily,periodic
checking is advisable.
To gain full access it is easier to take
the rear wheel off. This is probably why
Innocenti changed toafixed type.
However,ifyou replace the 6mm thread
pinch bolt to one with an Allen key head,
it is possible to tighten it up much easier.
Make sure if you do the replacement bolt
is long enough to go through the entire
length of the thread to avoid it stripping
when it is fully tightened.
Now concentrate on the end that is
connected to the tie bar,which is the
same for both types, fixed or two-piece.
Not only does the hole on the tie bar wear
and elongate, but over time the fixing
point on the gear shaft does as it is only
6mm wide. Replacing the tie bar is easy
enough, as is the top onatwo-piece shaft.
However,the fixed GP type requires the
whole transmission to be removed if it
needs replacing.Asolution to this is to
replace the worn part on the top with a
stud. The benefit of this is that not only is
it replaceable without stripping the
transmission down, but also it does away
with the awkward little circlip that holds
the tie bar in place. Instead usea6mm
nyloc nut to hold it in position, making it
far more secure and much easier to
remove when required. Start off by cutting
the top off where the tie bar locates on to
it and filling the surface flat. Drillahole
straight through it 5.5mm wide, then
usinga6mm tap, cutathread into it. The
stud needs to haveathread on top, but be
clear where the tie bar sits. The best one
to use is what is fitted into the casing to
hold the rear wheel end plate bearing in.
This hasalong enough thread to go into
the gear shaft with enough clearance for
the tie bar to sit anda long enough thread
to winda6mm nyloc nut on to it. Always
fit awasher under the nyloc nut and
tighten so there isa1mm gap between it
and the tie bar to give enough free
movement. Not only is it easier to undo
rather than try to remove the small circlip
it is replacing, but also if the stud does
wear over time it is simple to change.
Quite often an overlooked are where
play in the linkage can occur is with the
bush that holds the gear shaft in position.
This is made from brass and is around
20mm in length. Though you wouldn’t
think it, once worn it can exaggerate the
play on the linkage quite considerably.
Changing it is quite easy,onlyrequiring it
to be drifted out andanew one tapped
back into position. The only problem is
that the gearbox will have to be stripped
to do so. It’salways worth remembering if
Above:With the correct length trunnion in position it will fit all the way to the bottom of the pivot, and clearly shows the hole for the gear cable is clear.
Above:If theshorterlength trunnion is fitted on this
side of the pivot it doesn’t sit in the bottom correctly
and will wear the top half pretty quickly
Right:Always check there is enough clearance for the
pivot to move over the number stamp area on the
casing. If it is to close this issue can be solved by fitting
asmall shim underneath the top piece of the pivot
94 |SCOOTERING|AUGUST2019
