5 to 7 mph over is safe on most Calif freeways in open areas.
I-5 once out of LA and except for a short section thru Sacramento is all open area.
I find at 80+ you'll still get overtaken by faster traffic.
Just go with the flow and look for that faster "rabbit" to pace about 1/4 mile behind and try not to stand out by making erratic lane changes.
If stopped (it can happen) here's my story and I'm sticking to it:
I point out the wonderful safety features of the motorcycle, the good condition of my tires, the excellent road and weather conditions (if applicable), my many years of riding experience and that I use my turnsignals for lane changes so I can claim I was driving safely.
I then point out that my "spirited pace" was for MY saftey (never deny or admit you were speeding) and I was trying to keep with the traffic flow to avoid tailgaters since I am the smallest vehicle on the hwy.
If a friendly conversation with the officer results in a citation follow the instructions and request "Trial by Declaration".
If that fails, Traffic School on-line is quick way to get it off your record.
Remember "Lanesharing" is tolerated in California at the discretion of the officer but not elsewhere.
It's somewhat nerveracking on an LT due to width of mirrors (make sure mirrors are tethered)
I only "split/share" between the farthest 2 left lanes and once traffic moves about 40-45 I stay in line.
Riding on the right or left shoulder is never allowed.
Proceed at your own risk depending on your own personal comfort level.
I take no credit/blame for any "Performance Awards" acquired.
Have a safe ride.