My 2007 sporty won't start. It tries to turn over than stalls, and just afterwards there is a gurgling noise like a hungry stomach. It had work recently to attach exhast system back on, but the bike ran smoothly on test run the day before.
This is from the Electrical Diagnostic for an 08 Sportster so keep that in mind, but it might help you out.
Since you just changed the exhaust I would be looking for something that might have been disturbed during the change.
I hope this help some
