You might find this write-up bt Gandalf useful
Device: Freeze-Alert Thermometer from Big Bike Parts (http://www.bigbikeparts.com/
Digital 5 Function Volt Meter
Volt meter, clock, stopwatch, lap counter and ice alert thermometer.
Measures 11/16" x 1" x 5 1/2"
Velcro tape for installation almost anywhere on any bike model.
Part number 4-239
This device includes clock (12 hour or 24 hour), stopwatch w/lap time, a volt meter with LED indicators, a beeper for low voltage, indoor-outdoor thermometer w/high-low memory and freeze (or black ice) warning. Obviously, this is designed for autos but it is small enough for bikes and combines valuable indicators like the volt reading and clock for $27.00 in a LCD readout.
I chose to wire mine up through the head light harness. This would keep the connections somewhat protected. You can wire it to anywhere you can find the needed power sources. The devise has a ribbon of three wires, black (ground), orange (switched 12v supply), and red (constant 12v supply). Remove the headlight and locate the two accessory wires. One will be black/yellow (ground) and the other blue/white (constant 12v source). Next find any switched 12v source that is only hot when the key is turned to accessories. I used the brown wire connected to the tach and gas gauge. Splice into these wires either by soldering (preferred) or crimp splicers. [I couldn't find any crimp splicers small enough for the clock's wires]. If you solder, wrap the splices with electrical tape. You should now see the LCD display light up and indicate the time/voltage/temperature. It will stay lighted constantly but only draws about .5ma.
I wanted to make a quick disconnect so I could take the clock off. The wires are small leading to the clock, about the same size as phone wires. I had some old modular phone jacks laying around so I used them. I cut the wires from the male and female jacks and severed the wire ribbon to the clock. Match the wire colors of the clock to the phone wires as closely as possible. It doesn't really matter which is which as long as you make sure you do the same at the other end. After soldering the matched wires everything worked. All that's left is to tuck away all the extra wire and place the clock in a convenient place. The wire for the outdoor temp sensor I simply let dangle.
On the 750 about the only place is on the handlebar clamp. Velcro tabs come with the device but don't really do the job. I was afraid the Velcro wouldn't hold under the vibration of the bike. You can find your own method to affix the clock to the bike, but here's what I did.
I went to a craft store and bought one of those heat shrink bags that go over gift baskets. It comes in larger rolls as well, but I didn't need that much. I cut a section of the heat shrink wrap large enough to extend about two inches past the end of the clock and would overlap itself on the back of the clock. Next I slipped a flat cable tie under and through the wrap. Tape the ends of the wrap and along the edge of the overlap. Using a hairdryer I stretched the plastic flat against the face of the clock and proceeded around the rest of the clock. The final result is a fully encapsulated instrument which keeps moisture away and still gives you access to manipulate the controls. It is somewhat difficult to change from clock to stopwatch and from Fahrenheit to Celsius and to set the clock but it can be done. I don't know if the indoor sensor (on the unit) will give an erroneous reading because it is now encased in plastic acting as a greenhouse so the outdoor setting might be more accurate.
The last step is to cut the attached cable tie to size leaving enough tie to wrap two reusable cable ties around it and the handlebar. This allows you to remove the clock when needed. As an alternative (and I might try this later), instead of a cable tie inserted along the back of the clock, something more flexible like the packing straps that hold boxes of copy paper together might be better. A nice thing about using heat shrink is you can easily cut it away and start over. I'm sure you can find a better way to mount the clock depending on your bike but the shrink wrap is an easy and cheap way to protect the instrument.
Starting the bike for the first time with everything installed I got the low voltage beeper (bike hadn't been started for a couple of weeks). It stopped after the bike idled for a minute. On the ride the clock was rock solid and monitored the voltage. Just one last word...don't spend too much time watching the clock, voltage, or temperature. Keep your eyes on the road!