Assuming that the drag of a light vehicle is the same as a heavy vehicle, then the heavy vehicle would coast longer since the extra kinetic energy from the extra mass would take longer to dissipate. I think that the heavier vehicle would have higher friction from rolling resistance (more deformation of the tires and bearing resistance) but if it is not strictly proportional to the mass, then assuming lower, it should coast longer. I am assuming the difference in drag would be minimal particularly as they slow down.

Of course in space they'd all coast for the same amount of time.

Cheers,

rcomeau

I don't know the mechanicals of the Insight. You should be able to test whether regen is interfering by feathering the throttle (leave the car in gear). That's how we do it in the Prius. There can be significant drag in transmissions (the FEH uses a similar system to the Prius so no CVT really and not much in gears). Time to check the transmission oil in the Insight?

Pearl is a
2007 Driftwood Pearl Prius
Package "B" (everything but leather, nav, and rear camera)

You bought a used Insight. Do you know if the currently installed replacement tires are low rolling resistance?

It has the correct tires, and they are slightly over inflated.
I'm getting better than published MPG.

I just thought of one tidbit. The Insight has "new" OEM tires, just 5k on them.
The Escape has "old" OEM tires, 65k on them.

Going over camel humps in the road, I always figured a bowling ball and a golf ball would roll the same distance, putting air resistance aside. The momentum of the bowling ball would do more damage if it hit something in motion, but I don't think it would coast further up the next hill. Extra mass = extra gravitational pull... both on the uphill and downhill.

So for some reason, I feel the Insight has some drag that is not obvious.
It may boil down to its extreemly light weight means bumps and cracks in the road slow it down more than expected.

I can coast those camel humps in "Neutral" in the Escape.
I need to use gas on the uphill side when in the Insight.
I'm sure no laws of physics are being broken.
I just find that really interesting.

Assuming nothing is mechanically causing extra drag in your Insight it might be a feather vs golf ball thing. In a vacuum they would fall at the same rate but in air the feather is clearly going to lose the race to the ground.

It still seems weird to me......

John,

Is there any way you can hook up with another Insight driver and do a glide competition to see what happens?

Maybe more realistic, find a level place, and see how far you glide from say - 20 or 30mph and compare notes online?

61.5mpg lifetime - 82mpg in recent months

Best Run >
www.cleanmpg.com

"fanatic" is what the lazy call the dedicated

Okay, I will try that, but keep in mind I was saying the glide in a Ford Escape is HUGE and the glide ability in the Insight is slight by comparison of those two.

I'm not thinking my Insight is "broken". I get great MPG overall, great glide or not.