I installed a Throttlemeister cruise control/grip lock last eve. I have the Deluxe F6B with heated grips. I've installed several over the years on a variety of bikes, so am familiar with the process.

I found the supplied single aluminum spacer (1/8" thick) to be inadequate (too narrow) to mesh the rubber friction collar/aluminum spacer assembly that the rotatable brass end bushing contacts with the internal plastic grip base. If that part is loose, the rubber throttle lock collar can rotate and won't work as advertised. Apparently some of Honda's as-built grips require two 1/8" spacers, or a single 1/4" ring on my bike. Others may require less.

I called the good folks at Throttlemeister (414-464-6060) and explained the issue. They're sending me a new rubber friction sleeve and thicker aluminum spacer ring. Great service!

If you plan to install one, remove the factory end weight and measure the distance between the end of the right rubber grip and the internal plastic form it's bonded to and rotates with. Get whatever spacer thickness is required to close that distance (1/4" in my case). I had an aluminum crush washer with the correct OD, ID, and thickness to fill the void handy so it went together and works as advertised.

See, yet another Honda crush washer thread without even trying.