2006 street Bob running on one cylinder
 

My 2006 street Bob decided to only run on one cylinder toady after a run out.
It's the rear cylinder, checked for a spark and the plug is sparking fine. Doesn't seem to be getting fuel.Used to have a hyper charger on it and fuel pack, but now it's back to standard. It has done about 200 miles since put it back to standard as the fuel pack was playing up.
Any ideas on what to check would be appreciated.