Letters and emails only do so much. What you need is face time. Schedule an appointment with your local reps/supervisors/whatever you call them locally. What you need is someone to sponsor a bill. Make it personal and befriend your reps.
+1 on the face time with a sympathetic ear.
Having employed this method for my work, it might also be helpful if you know exactly what Georgia (or whichever state) law says about this specific matter, then be prepared to offer your own suggestion of what the language should say. Legislators often accept drafts of specific verbiage as a starting point.
For example, Louisiana law says:
§191.1. Operating motorcycles on roadways laned for traffic
A. All motorcycles are entitled to full use of a lane and no motor vehicle shall be driven in such manner as to deprive any motorcycle of the full use of a lane. This Subsection shall not apply to motorcycles operated two abreast in a single lane.
B. The operator of a motorcycle shall not overtake and pass in the same lane occupied by the vehicle being overtaken.
C. No person shall operate a motorcycle between lanes of traffic or between adjacent lines or rows of vehicles.
D. Motorcycles shall not be operated more than two abreast in a single lane.
E. Subsections B and C shall not apply to police officers in the performance of their official duties.
Added by Acts 1970, No. 538, §5; Acts 1999, No. 631, §1.
As an example, I would change the language of subsection C to read: "No person shall operate a motorcycle between lanes of traffic or between adjacent lines or rows of vehicles, except on Interstates and Louisiana state highways within city limits where traffic has slowed to less then 25 mph. Motorcycles may operate no more than 15 mph faster than the flow and only when it is safe to do so."
I'm sure the particulars would vary, but you get the idea.