That's your clutch
what kind of noise?
it may b the transmission sensor
the gears of the window regulator are stripped, the mechanism needs replaced.
Your transmission will slip and clunk or bang when changing gears, can have trouble changing thru the rand of gears, ans will eventually over heat and burn out.
They have 5 gears.
Bottle of Lucas transmission Fix, if that doesn't work, rebuild transmission
The engine is turning more revolutions at the lower gear. Once you shift into a higher gear the rpms drop.
the gear is located on the speed sensor, but the speedo is electronic so you can program it instead...
the Honda xr 80 has 4