I ride quite frequently, and often interstate trips.
Agree with forum members above who advocate for shoulder rigs. I use Galco, they make a reliable harness. Shoulder rigs secure the firearm while traveling, and on those occasions where you absolutely must use a toilet at a gas station you don't wind up either with a pistol on the floor, or a pistol in your hand or hanging from a coat hook on the back of the door. (If there is a door.)
The only drawback is that they are utterly useless in the extremely improbable event that someone aims a gun at you while you're riding.
Your first option is maneuverability - often bikes can outdistance and outmaneuver cars and trucks. If you've lived a life of sin and impure thoughts, however, and your aggressor is determined, the ability to pull a J-frame with your left hand and use it at close range would be advisable.
I will deny all accusations of a lifetime of sin, but allow as how I use a left-handed Safariland J-frame holster on a drop panel, attached with Safariland's quick-locking system kit. It keeps the revolver handy (to your left - non-throttle - hand) while riding, in a semi-open carry mode. Upon stopping, if necessary, you can pop off the holster and revolver and secure it elsewhere, then rapidly don it again when shoving off.
See the links below. It works for me. Just an opinion.
https://safariland.com/products/quick-locking-system-kit-23136
https://safariland.com/products/cubl-cantable-universal-belt-loop-with-qls-22l-receiver-plate
https://safariland.com/products/mod...nt-paddle-belt-loop-holster-with-detent-30575
[shown with a semi-auto holsters, however, this holster is also made for S&W J-Frames]
As noted in post #17, opinions will vary. I've been carrying on motorcycles for nearly 30 years and have tried a wide variety of options. This is what works best for me and the riding I do consistently.
Your mileage may vary.