What size speakers does an FLHTC have? And, can I use aftermarket speakers from Bestbuy?

Let me know.

 

I believe the speakers are 5.25". I am not sure if the speakers at BestBuy are Marine/Boat speakers, but you want speakers that are moisture and weather resistant.

 

The ohms on the aftermarket speakers need to match your head unit output. Different HD years have different head units that are 2ohms, 4ohms and 8ohms. They must be matched or you will damage your head unit. Most modern quality speakers will withstand the weathering.

 

They're five and a quarters. Why go Best Buy? Crutchfield gives you the most bang for the buck.

 

try emailing firecap501 here and cheeck out his arc audio amp and speakers. best setup on the market. tell him blue sent you