We have measured on our dyno with a powervalve positioning sensor (see picture) on which pressure and revolutions the valve starts to open . For the most common settings we have developed this system where you still will be able to regulate it up or down with an accurate click system.

For example with an original KTM exhaust you have to turn it out 5 to 7 clicks but for a HGS exhaust you must turn it out 9 to 11 clicks,the FMF 10-13 clicks out because these exhausts will give you less back pressure

Therefore it is important that when you mount the exhaust front pipe you also change the VITON O-rings in the front of the exhaust just to be sure it is not leaking !