Cooling Circuit; Balance Gear; Ignition Unit - Rotax Rm 1 Benutzerhandbuch

1.2.7. Cooling circuit

The coolant is pumped from the radiator to the water
pump which is driven by the clutch shaft. The water
pump conveys the coolant through the cylinder and the
cylinder head back to the radiator.
The cooling circuit is equipped with a thermostat
(opening point 45° C / 113° F). It assures that the
engine reaches quickly its operating temperature and
keeps it at a relatively constant level.
The thermostat is integrated in the cylinder head.

1.2.8. Balance gear

The balance gear is fitted on the clutch shaft. It is driven by the crankshaft, rotating in the opposite
sense and hereby reduces engine vibrations.

1.2.9. Ignition unit

The ignition timing is set by a digitally controlled battery ignition unit especially developed for this
engine, consisting of an ignition pick-up on the crankcase and an ignition coil with integrated
electronics. No manual adjustment is neccessary and possible.
This ignition unit cannot be used for engine type FR 125 MAX.
The ignition unit is equipped with an r.p.m. limiter allowing a maximum of 13.800 r.p.m. The r.p.m.
limiter starts already at 13.750 r.p.m. to partially interrupt the ignition.
Also at engine standstill the ignition unit consumes current. To avoid stopping of engine and
discharging of battery at standstill the electric circuit for the ignition unit has to be interrupted by
setting the switch to "OFF" position.
The ignition electronics are designed to reverse the engine rotation sense – without mechanical
gears – to allow reverse drive of the vehicle.
1.2.10. Electronic shifting assistance (ESA)
To optimize the shifting out of the 1
from the gearbox and gearshifting is faster and less strainfull for the gearbox.
1.2.11. Electronic reverse gear (RER)
The electronic reverse gear patented by ROTAX is activated at idle speed via a push-button and
provokes an extremely advanced ignition timing causing reverse rotation of the engine.
The reverse gear is intended only for reverse driving outside the race track. The engine speed is
limited by the r.p.m. limiter to max. 6.050 r.p.m. The r.p.m. limiter starts already at 6.000 r.p.m. to
partially interrupt the ignition.
Seite/page 77/132
Operator`s Manual RM1
st
gear the ignition is interrupted for 0,04 sec. This releases load
ROTAX KART RM1 Ausgabe/Edition 05/2003