MAN048 ING
26
10 EXHAUST SYSTEM
Before every test, make sure that the flexible is not damaged. Replace if
necessary.
ATTENTION:
In case the flexible is damaged, metallic particles could be sucked in the engine
and cause a seizure.
Always make sure that the springs are well hooked and in place. In case of breakage,
replace the broken spring.
Never race the kart without the 3 springs in place,
as
otherwise the exhaust pipe could vibrate beyond control.
Every 10
¸
15 hours, open the pipe end and make sure that the holes on the internal
counter cone are not plugged.
The best performance is achieved with a total exhaust lenght of:
§
L = 410÷415 mm.
Where L is measured from the flange on the exhaust header up to the first welding on
the first cone of the exhaust muffler (see drawing).
To achieve this dimension, the flexible (supplied with the engine) must be cut at a
lenght of 65mm (flexible completely closed).
Having fixed a sprocket ratio, it could be necessary to improve the engine performance
either at low or at high RPM.
This could be achieved by modifying the exhaust lenght.
In general, by shortening the total exhaust lenght an improvement at high RPM is
achieved and vice versa, by lenghtening the exhaust lenght the low RPM is improved.
When testing, never exceed in lenghtening or shortening the flexible by more than
5mm per time.
11 CENTRIFUGAL CLUTCH
The engine has a low maintenance dry centrifugal clutch.The following prescriptions, if
carefully followed, will allow a long clutch life.
When starting the engine make sure that the brake pedal is fully pressed to avoid
sudden accelerations.
