Here, I have two such switches. The red one is my heated grips. The white one turns off my headlight.
Not as good a design as above - low heat works by wasting power in a resistor which has to sit somewhere in your bike and get hot. Also reported to be a bit "flimsy."
Keeps your horn from beeping if you bump it into your tank bag. Photo, idea, and machining by Keith Rosendahl. Note the weight-reducing holes. He also has polished his bar end weights. Keith is a very good machinist with entirely too much free time.
Using some Velcro One Wrap, tie your front brake lever to the throttle. Idea and photo by Paul Fox.
The trick is to polish them to a chrome-like finish. They will darken to what looks like a black chrome if you just leave them alone, or you can polish them a bit on the bike from time to time, or spray a thin coat of clear lacquer on them to keep them shiny.
This work should be done wearing a face mask, as I think there's a fair amount of lead in these pieces. At the hardware store, buy about a 5" piece of 1/4" threaded stock, a couple of nuts, and a spacer. Run the threaded stock through a bar end weight, use the spacer on the outside portion, then lock it tight with a nut on each side. Chuck this into a drill press. Use 200 grit or so to cut through the paint, then with scotchbrite pads, blue then grey. Finish off with a polishing compound like semi-chrome. Lacquer must be put on in several very light coats or it will tend to fish-eye. Idea by Keith Rosendahl, picture by A J Parker.
Buy a 1" diameter 3/16" rubber o-ring at your hardware store in the plumbing section. When you want to lock your throttle, put it between your bar end weight and your throttle grip. Otherwise roll it onto the bar end weight. You might need one or two 7/8" diameter 1/8" rubber o-rings also. If you don't have bar end weights, you can use a 1½" o-ring or a loop of clothes line between the throttle grip and the switch housing. Alternative: buy a large o-ring fromCaterpiller depending on the diameter of your handlebar weights. About $2. The silicone O-ring has better to UV resistance, the nitrile O-ring is a harder material that should wear better. Thanks to R.Cairns of OZ for the detailed info.