![.wee. .wee. .wee.](https://motorbicycling.com/images/smilies/wee.gif)
the reason being is it lets more air into the Engine and that means better porormance ...
some bad points --- The engine will idle a TINE bit more when the cluch is in and all you do is cover the whole with finger and it goes normal ... .
Some REAlly good points ... -- It makes it much better in porformance and if you want to slow down with out using brakes just cover holl
![cvlt1 cvlt1 cvlt1](https://motorbicycling.com/images/smilies/cvlt1.gif)
hope this helps