GSX1400 Owners .org

Does the tank have a breather in it?  If so where is it?
The reason I ask is I went out this morning and the bike ran as rough fu*k.  I stopped to top the tank and it ran perfectly back home and I only put a gallon in.

Yes it does - there is a rubber pipe which runs under the tank, down the RH side of the frame (behind the engine), exiting out between the swing arm. If you have had your tank off recently it would have come out with the tank.

Regards running rough - how low on fuel were you? Sometimes if very low on fuel, it all flows to the back so the pump scavenges a bit (its a "feature" of the 14) - if you put a gallon in that may have been enough to keep the pump covered in fuel even when it was sloshing about the bottom of the tank

I thought that was the overflow pipe, but will check it's not crimped anyway.  As for fuel I topped it up a gallon, so I had 4 still in the tank so it was not low.  It was just odd that it ran crap until I topped up then ran fine, the last time I had this I had a blocked breather but not sure if it would be the same with FI and a pump.