I bought this Dyna from a guy who had a binder full of maintenance reciepts and manuals for every aftermarket part he installed on it. A very well taken care of bike. I have put ~4k miles on it without issue.

The only major thing I have done to it is swap out the stock slip ons (i think he drilled the baffles out) for Full Boar Exhaust Angle Cut Slip-On Mufflers with 2" Baffles : 222-947

I did this over the winter and have rode it a bunch without issue. The 2 times I have taken itover 50mph on the highway I had some strange things happen. 1st time the bike would not hold idle and if it dropped below 2000 it would stall out. I got home because I manually kepth the throttle up. Restarted the bike and it was fine with no issue.

Today, I got it up to 65-70 mph and shortly after when I was going about 40 i heard a high pitched coughing sound coming from the engine...scared the hell out of me, did not sound good. I pulled over, shut it off and gave it a few minutes. Restarted no problem with some light coughing and i kept the rpms under 2500 and rode home.

It seeps when the enging gets hot o=r i get it up to highway speeds Im having issues....any ideas??

 

Stalling when coming to a stop could just be a dirty IAC, so get some throttle body cleaner and clear it out.
Problems when the motor gets hot can be an intake or exhaust leak.
Also, check for codes.