On the ball slappy, it closes completely to reduce wheel spin :rollin :rollin :rollin
However it makes it easier to service the EXUP valve that is if you had an EXUP valve.
Tommy that link I gave you might be a good investment as it has all the bits you need and according to the seller (sellers on Ebay never lie :b ) in good working order.
However it makes it easier to service the EXUP valve that is if you had an EXUP valve.
Tommy that link I gave you might be a good investment as it has all the bits you need and according to the seller (sellers on Ebay never lie :b ) in good working order.