Like many others, i have both & love them.

 

Guys, I hate to tell you, but there is no free lunch! Anytime you shorten (lower) an antenna used for "line of sight" ( and that is what FM and CB are, except for "skip") it is not as sensitive and will let you know that in rural areas. I am not an antenna wizard but am a licensed amateur radio operator. good luck with the shorties though!

 

Installed over Christmas holiday. Simple screw on replacement and I've not noticed any degradation in the signal.

I have an 08 UG. There is a different set of part numbers, I think, for earlier models...don't know if they have more problems

 

Regarding the shorty signal strength.

I use the Zumo XM radio when touring so I don't need to worry about the range. I use CB for short, inter-bike commuications or to talk with over the road trucks on long trips

 

How much shorter are these than the stock antenna on the 09 SG?

 

I took the cheap route. I trimmed mine down and it works great.

 

Yeah, I am too....know some antenna theory...but...I just put both of em on my 08 UC, and, just sittin' in the driveway listening to 'em, they don't seem to reduce reception all that much, not noticeably, anyway. I've never used the CB to transmit, even with the OEM whip, so I may never know if the short antenna results in reduced performance, but I'll deal with that if/when I ever have to - I still have the long one.

 

I got both and love them. No change in reception and the best part is my bike no longer looks like some kids radio controlled toy

 

Are the HD's taller than the JM's?

 

My friend bought the Harley Davidson shorty antennas last week. His 08 ultra was in his garage with the radio playing loud and clear. Changed to the shorty and it would barely receive the same station. The shorties are for sale. Maybe they work in town but not out in the country and far from the station.