Most motorcycle throttles are controlled with the right hand. If your need to deploy your weapon while maintaining your speed, your weapon must be deployed using the left hand.
My one experience in being required to deploy my 1911 while riding almost resulted in a disaster.
The problem was that I am right handed and pistol was on my right hip. Unfortunately, the situation required that I keep my throttle open with my right hand. In short I could not use the pistol.
Fortunately, I had a spare chain which I put through the windshield of the PU which was attempting to kill me. The chain ended the encounter.
Now when I ride my 1911 is accessible to my left hand and will be deployed weak hand.