You can buy a cheap "noid" light to see if the injectors are getting a signal from the ECM. At least that part of the equation is solved.
Also if the cylinder is dry is an indication that there's no fuel going into it. The exhaust port will appear fluffy white in color versus fluffy charcoal colored. Compare front and rear cylinders.
Removing and sending the injectors for testing could be less expensive than replacing them from the last pricing I did on Harley injectors ! $150.00 plus per !!! Like dang, them babies are $ expensive !
As a side note, I've never had to replace a faulty Harley injector. I've replaced them as a SE upgrades only.
We've sent them to those folks under the suspicion that they were spraying "X amount", when they were in reality, not. Joe's Cycle Repair |Mechanicville NY uses their services quite often, and that is how we had learned about them.