Hi all, I just bought an AR and there's a PV problem. It doesn't open as the rev's rise.
If I open it manually and then start the bike , the bike shuts it automatically but as the revs rise it won't open again. Do you think this is a computer problem (if so why does it still know to shut the valve at start-up)?
What else should I check?

Try checking the pv cables. I had one break once with the same symptoms you'v got. Good luck

Tried that Gwynn but cables all OK. If i twist the servo motor by hand valve opens and closes.

i am sorry but this sounds like the typical "ooh my AR's gone flat - time to get shut quick"
sorry for sounding harsh, but its quite common for people to sell bikes when they found out hte price of a new CDI / PV motor
if you can determine which part has failed, davidsilverspares is your best bet for new. unlikely to find a good working second hand item.
best of luck as once its right, they simply are sublime

hello steve.
this will sound unthinkable, but I had same problem with mine, make sure the cables are conected the right way, as mine had been refitted by last owner with the pivet arm on back to front, when you opened the throttle the PV closed, and visa versa.
hope you sort it.