When i put my C57's in i had idle problems, but changed the base idle and set the co2 to 3.5 - 4.0 % and managed to iron out the idle prob, Also with regards to the idle valve, take it out and soak it on petrol for the night or WD 40 then put it back in, if it starts to idle erracticly give it a "TAP" with a spanner and it should stop.

Give it a try...


Cheers

Alex.......