right ive orderd one off these for sum reson and i dont no what it is or what it does? is it like a taque driver? a belt pulley whats that? where it go ect? wtf is it?
It's part of your front pulley. As standard they have cooling fins on them. On the left in this picture. The one in your picture is an aftermarket one with no fins meaning less drag on the crank leading to more performance. The problem with that is there is no cooling so they are pretty much only suited to sprinting.
it will respond quicker (rev out quicker) and give slight power increase. i never run the fans on 70 engines but with a piaggio engine you can take a little plastic cover off to let air in (dirt/water also get in unfortunatly but it stays cool enuff to not melt the belt)
