I own a Ford Escape Hybrid. Curb weight is 3850 pounds.
I own a Honda Insight. Curb weight is 1900 pounds.

The FEH is high off the ground, and shaped like a brick.
The Insight is low to the ground, and is tear-drop shaped.

The FEH coasts like a puck on an air hockey table.
Sometimes it feels like I am accelerating in neutral at 25 MPH on flat ground.

The Insight coasts like a drag racer, after the parachute has been deployed.
The Insight loses speed on a 3-4% downslope in neutral at 25 MPH.

So what are possible reasons? The Insight is great for highway driving, but it feels like such a drag, man, when coasting around town. It does not coast worth beans.

Rule out the obvious like draging brake pads... I have gone 5000 miles in 2 months and I've never seen or smelled any smoke or hot smell.

The funny part is, the Inisght is a Manual 5 speed, so neutral should be honest to god neutral. The Escape has a CVT, and is never actually in neutral. Neutral just means all power is removed from the electric motors. They are still spinning.

Does the FEH really have a significant flywheel effect because of this?

It's really a drag using the Insight in town. You have to keep your foot on the gas approching stoplights, something I was totally conditioned against using the FEH for 3 years. The Insight is a joy on the highway. ( 75 to 100 MPG highway based on top speed and weather conditions. I just did a 54 mile highway section at 55 MPH and net 103 MPG because I had a tail wind. )

The weight might have something to do with it honestly, my 15 passanger 1 ton 3500 Dodge ram van (6500lbs or something?) seems to coast better and farther than my feh, even thought the feh really does pretty good. There are hills I can coast down one side and make it all the way up the other without touching the accelerator in the van, but the FEH doesn't make it more than 3/4 the way up the other side. Of course the heavy van takes a lot more fuel to get moving than the escape, and likewise the escape verses the insight.

Jeff Jones

2006 FWD FEH,
hopefully one day to be a PHEV (pet project)

Curious, you would think that the aerodynamics and low rolling resistance tires would allow the Insight to coast for ever......

My hybrid coasts a lot farther than my non-hybrid......

Both cars coast a lot better when it is warmer......

Any formula for rolling distance in neutral MUST take into account the mass of the vehicle. E=Mass * Acceleration. Reducing the mass greatly reduces the kinetic energy. The difference in aerodynamics is most likely not that extreme, as the total frontal area is close. (not a Mack truck). But the upside is it takes less energy to accelerate. All of this is painfully clear when you play around with bullet ballistics.

Ducit Amour Hybridae
Mark Smith
Master Certifited Technician
Tempus non reparabilis fugit
"It isn't pollution that's harming the environment. It's the impurities in our air and water that are doing it."

Best Tank 35.0 MPG

Hi,

Let's start by looking at the vehicle cross-section and mass. If you can, park the Insight and FEH so the front bumpers are aligned and take a photo about headlight high of the two cars together. We can then overlay the photo with a grid and count the squares to figure out the aerodynamic cross section. Next list the weight of each vehicle. If you can get the aerodynamic coefficient of drag, that would be perfect.

The mass allows us to calculate the relative kinetic energy of each vehicle. The cross section from the photo and coefficient of drag gives the relative aerodynamic drag as a function of speed. But for a back of the envelope, the ratio of the cross section to the mass gives a good indication of how well the vehicles will coast on a flat surface.

Now the Insight has an aluminum body and a serious weight reduction. This means it will rapidly lose velocity In contrast, the FEH has a lot more mass per cross section so the loss of velocity will be less. Note this does not mean you'll get better performance by adding ballast to the Insight. You'll lose more from the energy needed to accelerate the Insight than you'll gain from extending the glide.

What I'd like to suggest is looking at techniques to improve smoothness of the accelerator. I recently posted a trick from AutoSpeed to add a throttle smoothing circuit to an Insight. This can keep the ICE in "lean burn" mode longer and measurably improve fuel economy.

Bob Wilson

Operation Iraqi Oil Freedom:

Automatic, stock, project car.

My other 1500 cc car:

Automatic, stock, backup car.
Free speech, dialog and knowledge thrives without the poison of SPAM.

Your Insight experience seems quite different than my own. My 2000 Insight feels like it will coast all day. Do you have the OEM tires aired up to the appropriate psi?

Good point!

Do you have a recent wheel alignment report? Rolling drag is important too.

Bob Wilson

Operation Iraqi Oil Freedom:

Automatic, stock, project car.

My other 1500 cc car:

Automatic, stock, backup car.
Free speech, dialog and knowledge thrives without the poison of SPAM.

I remember reading John had his Insight tire pressure at 55psi!

2005 AWD Escape Hybrid
Best Interstate tank trip MPG 39.02 (scangauge II) for 402 miles on I-70, 10.3 gallons used over mostly flat terrain. Aug. 2007

Best Interstate tank trip E30 MPG 34.6 for 271 miles along I-80 in Indiana and Ohio. May 2008

Best multiple road tank trip E30 MPG 36.2 for 202 miles in Southwestern Pa. July 2008.

Yes, I have my tires at 50psi when I'm down at the Mississippi. When I'm in Denver, that makes them about 55psi.

If alignment was poor, I don't think my MPG would be so high.
I routinely get 85-100 MPG now that winter is over. ( was getting 65-70 MPG in winter )

It is just DRAMATIC not slight, at how much less a 1900 pound car coasts compared to a 3800 pound one, and that is surprising to me.

I'm talking about slow speeds, as I don't try to neutral coast at high speeds. Thus, I would not think aerodynamics would be significant.
I'll do the side by side photo just because I think it will be fun!

I understand the whole kinetic energy thing.
But still, me on my bicycle ( 250 pounds combined ) seems to coast better than the Insight.
( Not proven, just gut feeling )
I'm a very scientific person. And something feels wierd here. I can't put my finger on it.
It's like there is invisible regen going on. Maybe there is???
It is physically possible for the Insight to make regen power in neutral?
Is there some funky electromagnetic drag I don't know about?

I have a pretty decent glide, but then at 1900 pounds, the momentium is limited

61.5mpg lifetime - 82mpg in recent months

Best Run >
www.cleanmpg.com

"fanatic" is what the lazy call the dedicated