I've been looking for a decent forum for a while and this seems to be the place.
Quick question, Like most ZZR250 owners i'm having some problems with my bike

Now i've paid to have the carbies removed stripped and cleaned with new neddles and seats installed. Picked the bike up today and it's still doing the same old, dies at idle when hot. Sounds like a mower on steroids etc. Occasionally the bike will idle perfectly and ride without the sound etc.
I've noticed that you all state the the fuel tank should drain when switched to PRI.
I've removed the tank prior to getting the work done and assumed the tank switch was vacume operated???? Is this correct? As my tank will not drain on PRI or RES. When i fix a tub to the vacume line and suck it will drain for a little bit then won't drain at all on both the PRI and RES settings??
Is this normal?? or is this really my problem after all. Should the tank drain with vacume on the PRI setting???? Can someone clarify?