Welcome to the forum Reese.As a Reciently Retired Marine of 26yrs, thank you for your Service. I will try to put some ideas towards your problem.
Since this is your First bike please take some notes and you will be suprised how easy the Buells can be With some Decient Maintenance.
Don't let this long Posting worry you there is somthing to learn ABOUT any machine you Purchase. Buells are fun and great handling Bikes. You will need to Set up the Suspension for your weight.You also CAN'T Blip the Throttle like a Foreign Bike, so Smooth is best right now, so here goes.
BUT first lets get you towards the Engine Idling Properly!
First have you [reset] your TPS-Throttle Position Sensor, it can be reset by a Key Turn Method along with Twisting the Throttle properly, you can find the Procedure here on the Forum.
Any time you start the bike you need to LET it Idle for a few minutes especially if it has set for a week or more 08+ Buells! Check your Fuel and if it has been sitting for a while then it [may] need to be changed. Fresh Fuel and just a small amount of SeaFoam(please read the directions)with a full tank will keep the injectors from clogging from sitting while you are away.
Also Check your Battery and the Terminals the Starter Could be jamed from low voltage. There are several areas of interest to check [all easy] to do. If your battery has been sitting more than Several Months with no maintenance done to the Battery then might want to remove the Battery and have it load tested OUT of the bike. Some Auto Parts Stores will check that for free.
Never JUMP Start the Bike with a Diesel vehicle. If you must jump start the Bike then Jump it with a Vehicle (Single Battery vehicle) NOT running at all. The Stock Battery is only 200/CCAmps and wouldn't take much to fry something in an Electrical area. Charge your battery before you try to start it so as to have the power to get it going.
The Same rules APPLY when using a Battery Charger. No Boosting, Let the charger do it's job, remove the cables and then start ,this way if there is a [problem] you don't Know about the Jumping OR Battery Charger won't make the problem Way Worse than it could be!
It's easy to UnPlug the Low beam Light on the Firebolt for more starting power.You don't need to but when checking it helps for a little more power. If you have a meter and get the Engine running most likely you will need to test (check)the Charging system once you get the bike to Idle properly. YOU will need to get a 27/Torx bit forc removal of the seat. When Reinstaloling the seat once done in that Area jusrt Snug those Bolts.
On a XB12R 08+ Buells the Stock Idle is at 1'100/RPMs, AND the Volts AT Idle will be 12.3 to 12.6-and will climb as the RPMs go up.
Remember the Newer Buells need the TPS reset more often than the Older Bikes.Do NOT Twist the Throttle if you are Trying to start the Engine 08+ buells, the ECM takes care of the Idling and resets every time you start the Bike.
IF you have Twisted the Throttle while starting then the TPS needs/ HAS to be done!
Never touch the Throttle when Starting the bike(Especially) a new one!
The TPS- Key Turn Method is easy to do and if you need that post up and one of us will post it for you.
I reset mine on my street bike 08/XB12R every TWO fillups so my bike Idles properly. The 09 XB12R I have is not Streetable it rides Tracks only but TPS has to be done Regularly!
I don't wait till it runs badly due to I just might need to Throttle out of a situation and it would SUCK if it spit and coughed causing something to happen that I could have prevented with a Simple task as an TPS reset! There are many other Tricks for in case you flooded the Engine, BUT we will start here with the Basics First! Hope this gets you in the Right Direction. Small Things First!*Jimi[cool]