Just to throw my two pennies in here.... I've used throttle locks from the Vista types to the factory set screw types to o-rings, washers and shims wedged between the grip and the bar end or switch housing. I liked that set up a lot. I'm still used to throttle on-throttle off with my hand and I do not let the grip self return. When I bought my '08 Royal Star, I saw those cruise control buttons over there on the throttle side switch assembly and thought, "That's just nuts.", and I was figuring out how to get a throttle lock on it while it was still on the show room floor.
Well, of course, I tried it out and it worked very well. It acted just like the modern factory automotive units I've used except softer on resuming. It was quite gentle actually but did reach a healthy throttle opening pretty quickly. It would allow me to accelerate to any throttle opening without kicking the unit off and self-resume when the set speed was re-reached. On the other hand, it would kick off at virtually any sign of throttle closure as well as clutch or brake use. I was impressed and never did put a throttle lock on it.
I had the misfortune to see the "guts" of the after two "boo boos" in two weeks. The control unit and actuator motor were tucked into each side of the plastic "mouth" that surrounds the radiator. If memory serves me, they were branded as Mitsubishi units. If they were spec'd by Yamaha or off the shelf stuff engineered in, I have no idea but, the system worked fabulously.
As far as hand movement and "speed creeping" while it was engaged, Yamaha did a really smart thing in my opinion. They put the biggest torpedo shaped bar end weights that I've ever seen on it. These things were like 4" long! When I engaged the cruise, I'd just slide my hand over to the bar end and let the throttle tube do it's thing. No sweat!
When i got the Royal, I had already damned the cruise control before I ever tried it. After using it, it remains the only thing that I miss from that bike that I wish I had on my Guzzi and my S10.
Oh, and for those interested...
Boo boo number one, it got backed into, sitting in a friends circular driveway by a carpenter in a Chevy C-30 with a utility bed on it. He hit it right in the tail light. The damage was (The big chunks.) windshield, right front signal, headlight shroud, radiator surround (where the cruise stuff is.), both right crash (Yeah,,, Right!) bars, right pannier and lid, rear fender and lights and the left pannier and lid along with a lot of little stuff. His insurance paid for everything. The bike was fully functional except the rear brake where the inadequate crash bar folded the floor board up. I rode it home, took pictures, and beat the offending crash bar forward before I rode it anywhere else.
Boo boo number two, I went on a charity ride with it before I got the settlement from boo boo number one and, well, there was a slight down hill grade to the church parking lot we were in. I staged where they told me to and shut her down. Just before I got off, I thought to myself, "Self, you may want to leave it in gear." So i thunked the shifter down into first. It felt like it took. It didn't... After goofing around with some guys for about fifteen minutes, I went and registered then attacked the barbeque! When i came back out and got to the bike, things were different..... One of the organizers came up and told me that it rolled off the side stand and of course, it got the left side this time... Nobody's fault but mine. Very embarrassing. Oh well..... :-[
Most Tonti framed Guzzis, like mine, have a locking side stand like the older H-Ds have. I don't care anymore, I'm using the side stand switch to shut e v e r y t h i n g that I ride off now and leaving them in 1st gear!! Lesson learned...
