Everyone says my transmission over the CB is "garbbled" can't understand me.
Has anyone run a extra ground wire from the antenna? or CB radio? to the frame?
installed the J&M shorty antenna but no difference in stock whip or J&M antennas....

 

Has the antenna (either one) been tuned with an SWR meter?

 

no, don't have a SWR meter.....

 

I don't think the J&M CB antenna is your problem. I'm not a technician, but have some experience with CB since the 60's. I have the J&M's too, and it works just fine. Garbled transmissions mean possible broken wire in the microphone, or an open circuit hearing ignition noise. First, check to see the coiled cord from your headset is intact. You can do this by using an ohm meter. Is there a windsock on the mike itself? Sometimes wind can make it hard to understand speech. If your riding a classic, did you add the CB module to the radio? Is the power connection shielded? Are your spark plugs the resistor kind? (Most radio equipped bikes are). Hope this helps.

SWR is more about range than clarity of transmission. On a bike, range is usually under two miles. J&M antennas come prematched to Harley systems.

 

I assume it's always been that way? I Had the same problem with my 2006 I jumped through all the hoops. Its not the SWR. You will loose some SWR with the shorter antennas but CB will still sound fine. Mine turned out to be the CB. I swapped cb's with a buddy who had the same year bike to finally eliminate or define theproblem. Itwas easy the problem was fixed when the radio was swapped. Its easy to do by removing the outter fairing shell. The cb sits on top of the radio. takes just a few minutes to swap them out and then you can see if it fixes the problem...