Having problems with my gs550.

When the bike was running, the engine would bog down while blipping the throttle and revs would climb really high and adjusting the idle, to bring revs down would just stop the engine, so adjust it up slightly and revs again would climb.

I stripped that carbs and removed the float bowl and floats and all jets to make sure everything was clean and not blocked, and it seemed ok so i cleaned it out just incase.

Carbs back on and evenually got it started but same problem. Discovered that a pipe wasnt connected to the carb from the fuel tap (vacum pipe) but now the bike refuses to start and im guessing its not getting fuel as my plugs are pretty dry even after whacking the throttle open trying to get it started which should have flooded the engine.

I did notice that on the bottom of the carb where the float bowls are there is a screw which looks like some kind of mixture screw. I took 1 out taking not how many turns it had to be out so that it went back to where it was and it is indead a jet, its tapered like the mixture screws.

They are pictured in the haynes manual but it doesnt say anything about it.

I also have a manual on cd-rom and all it says is do not touch this screw.

Im definatly getting fuel from the tank, i accidently left the fuel tap on the prime position one day and came back to find that 1 of my carbs had overflowed. So i know that fuel is getting into the carbs but it still doesnt seem to get that much to the engine.

Any ideas??

It looks like the previous owner may have rejected to suit the motad 4-1 exhaust and k&n filters that are on it as the main jet does not match the manual, manual says 80 main jet is 935??