ok guys, finally had enough of these dodgy valves which i can only fill up at garages rather than petrol station air pumps. apparently the problem is that the valves aren't long enough.
so, i need to id the type of monzas i have and match valves to that. went into the local vw garage and apparently i have denver wheels according to the parts department, monzas weren't available on the mk5 apparently. you can imagine my anger when i asked where the wheel id part number was and i got the reply "on the wheel". bunch of monkeys!
does anyone here know where i can find the part number for these bastad wheels so i can finally get to the bottom of what valves i need.