In a regular car, the optimum speed for mpg is the lowest speed in the highest gear -- getting the most forward propulsion with the lowest engine rpm.

But in the HCH2, the CVT makes optimum speed more difficult to find. It varies based on road grade and wind conditions. You can generally assume that low rpm is the priority. And since wind resistance quadruples whenever speed doubles, low speed also means high mpg.

So it comes down to how much your time spent driving is worth relative to your money spent on gas ..... or, sometimes, your bragging rights to a high mpg number on your dashboard display. After 23,000 miles, my "trip B" that I left running since the day I bought the HCH displays just over 47 mpg. That's not particularly high, but it's what I accept in order to cruise along with traffic @ 65 miles per hour and get where I'm going in reasonable time. Those 500 mile road trips would get awfully tedious if I stuck to the old "double nickel," even though doing so would get my average mpg up to the magic 50.

Around town, I find that 25 miles per hour is the optimum speed, because it's the lowest speed at which I can activate the cruise control. The mpg really goes up when you take your foot off the gas and let the computer regulate the speed.

However, on the highway, you can improve mpg with little sacrifice in speed by DE-activating cruise control on uphill grades. The cruise will rev the engine thousands of rpm to maintain speed, while your foot can let rpm rev only slightly, maintain a slightly lower speed, and save some gas.

That's one area with room for improvement on future HCHs -- if the driver could set a rev limit on cruise control, or if Honda could program the car to use up battery boost before increasing rpm, that would boost mpg.

This is all quite a long answer to a simple question. So I'll give you a simpler answer; After a year of ownership, I'd say that the optimum speeds for the HCH are 25 miles per hour in the city, and 50 miles per hour on the highway.

Those speeds will get you stellar lifetime mpg numbers. You'll just have to spend extra time in your car going places, and ignore the obscene gestures from your fellow motorists.
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