took my gs to mech. and still having problems

[rpkknives]

 I took the bike into the mechanic to get Carbs adjusted and a valve job done. As soon as I got it back to the house I tried starting it and it took a while like the Carbs weren't getting gas. Finally started so I took it for a ride, got a few miles down the road and it lost all throttle response then it died completely. I looked down at the new clear fuel hose that the mechanic just put on the reserve I believe, and there was allot of air in the line. It wouldn't start back up on any petcock position. I loaded the bike back on the truck and took it back to the mechanic and of course it started right up for him and he rode it around for about 10 minuets while I was there to see if it would act up again and it didn't.... both petcocks have been eliminated as a possible causes. The only thing I can think it might be is when we loaded it on the truck me and 3 other guys lifted the front tire on first then lifted the back tire on so it was at a steep incline enough to get a float in the crab stuck. Then when we took it off the truck and the front tire rolled off the bed of the truck and hit the ground it knocked the float back down. But I don't think that would explain the air in the fuel line. What do you guys think?

[adidasguy]

Air will get forced out by the gravity forcing the gas through.
Only one fuel line is used at a time.
If using main, then the reserve line is shut off. Air in there will stay until you switch to reserve. When you switch to reserve, the main is shut off.
When in PRIME, the reserve line is used.
So air in one line means nothing until you use that line and the air will get forced out due to gravity (unless you're out of gas)

[rpkknives]

All the other lines are regular cheap black fuel line so I couldn't see if there was air in any of the other lines. But as it was turning over the air just moved back and fourth in the line.

[adidasguy]

It will unless in reserve or on prime. Maybe you needed more gas in the tank?

[rpkknives]

I tried starting in reserve and prime position with no luck...