.11
Ports
When ports in cylinders are adjusted to the
dimensions specified in the homologation sheet,
material may only be removed in the specified
opening to a depth of 10mm not including liner, to
match the shape of the original adjacent connecting
passage (channel) outside the adjusted port
opening. This also applies to other openings in the
motor for which the dimensions are specified in the
homologation sheet. Should the modified port
window be smaller than the track, the track may not
be tampered with.
As Stock Class
Free
.12
Parts
No part of the engine can be changed with another
manufacture’s or pirate part, except for the tiller
arm. Tiller arm bracket, gear change lever
As per Stock Class
Parts may be changed with
another manufacture
.13
Air box
Maximum of 1 x 6 mm hole may be drilled in the
lowest part of the air box to allow water to drain
from it.
As per Stock Class
As per Stock Class
FREE
.14
Spark plugs
Original complete spark plugs and HT leads may be
replaced.
As per Stock Class
As per stock Class
.15
Auto lube &
engine mounts
All auto lube and any relevant parts may be
removed. Engine mountings may be replaced with
rigid or rubber mounts with similar characteristics.
As per Stock Class
As per stock Class
.16
Throttle lever
Springs may be added to the throttle lever of the
carburettors
Tohatsu D1 Throttle cam can be used on the Tohatsu
D2 Engine.
As per Stock Class
Free
.17
Emulsion tubes
Emulsion tubes are to be standard “off the shelf”
items and have the same pre-requisites as the jets.
No modifications are allowed to these parts
As per Stock Class
FREE
.18
Baffle plate
Baffle plate or other fuel surge preventative
measures can be taken in carburetor fuel bowls.
As per Stock Class
As per Stock Class
FREE
.19
Steering
It’s allowed to change bearings with similar
characteristics. Steering dampers may be fitted.
Steering by a tiller arm is required.
As per Stock Class
As per Stock Class
.20
Reeds
Standard reeds only as supplied by the manufacturer
for the specific model of engine
Reeds only are free.
The stoppers must not
be removed.
Free
.21
Machining:
Skimming, grinding or machining is allowed as long
as it meets the UIM homologation measurements.
As per Stock Class
Free
.22
Starters:
Electric starters are not allowed.
As per Stock Class
As per Stock Class
.23
Thermostats:
Thermostats of the cooling circuit may not be
removed.
As per Stock Class
FREE
.24
Revolution
limiters:
Rev Limiters, heat sensors and lighting coils must
not be removed. Rev limiter wire connections must
be continuous and must be soldered to achieve this.
Anything that might restrict the rev limiter in its
proper function will be classed as an infringement of
this rule. Ignorance of the above will not be
accepted as a defence and the competitor will be
disqualified.
Can be removed
Can be removed
.25
Jets:
Jets have to be to the UIM homologation
specification.
Free
Free
.26
Weight of part:
A part, the weight of which is quoted in the
homologation sheet, may be machined for the
specific purpose of reaching the quoted weight only.
It is not allowed to change the flywheel, but balance
machining is allowed if the dimensions and weights
are still correct
As per Stock Class
No restriction on weights quoted
