Your not going to get good bass unless you put 6x9 in the lids, and your not going to get clean sound above 60 mph no matter what anybody says or how much you spend; loud - yes, clean - no. Above 60 it's earbuds all the way!
That being said I put JL Audio C3 components in my CVO and they sound WAAY better than stock, if powered with a good amp. I'm in the process of putting Hertz HCX 690 in the lids, powered by the new Hawg Wired RS400 amp. Should sound good, hoping for good bass up to 60, we'll see.
Might be true about the bass, if you mean BOOM, BOOM, BOOM bass, but I have to disagree about clean sound above 60. On my '09 I had a pbr 300x4 running two RF coaxials in the fairing and two JL Audio coaxials in the lowers and it was clear as fast as I ever rode it once I put a 12" windshield or better on it.
On my '13 RG Ultra (I took the tourpak off), I installed one of the new hawg-wired RS400 amps running a set of alpine spr 60c components in the fairing and a pair of spr 60 coaxials in the lowers. I got rid of a couple of gauges for the tweeters on the components, but it is CLEAR! I spent:
$270 for the speakers
$399 for the amp
$50 for the ar65 6.5 speaker adapters(they install without cutting the OEM "nubs")
$50 for the amp install kit
$55 for HD lower fairing speaker pods
$18 for paint( I painted the lower pods vivid black myself)
$20 for speaker wire
A few bucks on misc connectors from Lowe's
400 watts and clear as I've ever heard on a motorcycle moving down the street at 70+ MPH. I have a cee bailey 15in TRSSC windshield.
I also found through trial and error, that your windshield is almost as important as your sound system.