does anyone know what the hole on top of inlet rubber is for.iv got a bike which is in bits with parts missing and cant work out why there is a hole there ,is there a part to go in there?

Parts list enjoy.

http://www.thehellteam.com.au/TECH/Rotax/S...y-PartList.pdf+

Rathmells still have some random bits for this bike 01423772885

The hole is for this. I beleive its a tank that improves low end torque by increasing the volume of the area between the carb and the motor.

thanks guys most helpful