Insight 4x4

[Hugh-Falls]

Has anyone considered adding motor(s) to drive the rear wheels of an Insight? This would be a way to add PHEV capability without getting involved with trying to modify the existing Honda engineering. By keeping the rear wheel drive separate, compatibility issues coud be avoided completely.

[Piwoslaw]

Kinda close:
Mike's 99mpg e-5th wheeled Insight

Instead of adding motors to the rear wheels, he just added another rear wheel!

[RobertSmalls]

Hi, Hugh.

If you're looking for a commercially available RWD donor vehicle, wait for someone to crash a Mitsubishi Imiev. Its battery is fairly small and manageable, too.

Aside from Mike Dabrowski's 5th wheel, there was also Team FourSight from the Automotive X-Prize. They put an EV drivetrain up front, and the diesel engine and tranny out of a euro-market Smart in the rear.

[Hugh-Falls]

Gentlemen, thank you for your observations and suggestions.

Of course, Mike Dabrowski's ingenious ground breaking E-Wheel is one solution and it shows the way one Etek motor can propel an Insight at about 23 mph. Maybe two (2) Etek motors can get you up to 46 mph or more, especially if the drive is efficiently done through the existing rear wheels rather than an additional wheel.

It is well known that an Insight will travel quite well on 13 HP. Two Etek motors combined develop about 12 HP and up. Mike's work has shown the kind of electrical loads we might expect from this motor in actual driving conditions. Two of these motors on an E-Wheel might work but the placement of a bulkier setup is a problem of finding the room. Locating any where off the rear axle centerline would subject the added wheel to side wear or scrubbing and loss of traction. Driving through the existing wheels has obvious advantages beyond the need for the additional wheel(s) and the need for the retract/extend mechanism.

[Hugh-Falls]

Belt drives on motorcycles typically are a little over one inch wide and carry considerably more torque than an Etek motor. A conservative estimate of a 3/4 inch wide belt for our final drive fits well within the working range shown on belt drive design tables.

If we allow for 1/8" to 1/4" clearance between belt and tire as do the motorcycle applications, we need to find 1" of space for our final drive. By tightening up the clearance between the fender well and our drive as compared to existing tire clearance on the inside and by adding a wheel spacer adapter, we can gain some additional space outside from existing tire/fender skirt clearance. A one inch wide space may be obtainable to shoe horn in our final drive without the need to modify the existing sheet metal and plastic.

[Staska]

This solution (poulsen hybrid, was mentioned here) would easier, and more universal. If you go for chain, it could be even possible to fit in 3/4 inch clearance.But any fitting inside wheel will not work, because hub is positioned in the middle of wheel..

[Hugh-Falls]

Final Drive Considerations

Most motorcycle final drives use a standard industrial 14m pitch belt and pulley arrangement between the transmission (small diameter) and (large diameter) at the rear wheel. There is quite a vast selection of pulleys available from both OEM and after market sources in aluminum and steel amongst the various motorcycle brands. Selecting the most desireable ratio to begin with and changing later on if needed would be pretty painless. Good cheap used motorcycle parts are readily found just about anywhere.

For instance, on some of its models past and present, Harleys use a 70 tooth aluminum sprocket/pulley about 13" outside diameter with one flange integrally cast into it. It uses a wide belt but it could be easily machined down for our 3/4" wide belt requirement and match up nicely with the 14" Insight wheel.

Fastening the pulley to drive the Insight wheel must be done in a way that will not interfere with normal tire changing. The best way would be to use an adapter that does not alter the existing Insight wheel in any way and would be therefore entirely separate from it. This pulley adapter could also contain the necessary wheel spacer. The pulley/adapter assembly would slip over the 9" brake drum, would be deep enough to extend beyond the tire and would fit over the wheel lugs before mounting the wheel.

[Ryland]

I haven't looked under an insight in a few years but is there any way to adapt the rear end from a Civic WagoVan to the insight? the wagovan came with a four wheel drive option so of all the vehicles that have rear wheel drive it seems like that one might fit with less modification, allowing for a larger single motor instead of hub motors.

[Hugh-Falls]

STASKA: Thank you for your suggestions.

Please note that Poulsen on their web site say that the system "WILL BE AVAILABLE" and quote a tentative price of $8600. Like the abomidable snowman there are a lot of news reports about it but unlike the yetti, there are few if any sightings. The picture you show us looks to me like a good "photoshop" job.

Just like another wheel, the drive adapter I propose is to be mounted on the hub between the brake drum and inside the existing Insight wheel and is to extend over the brake drum and past the tire to carry the drive pulley/sprocket between the fenderwell and inner side of the tire.

[Hugh-Falls]

RYLAND: Your suggestion to use an existing Civic Honda driven rear end would allow using existing Insight wheels and probably other parts well. I have not studied out the possibility of grafting the Civic driven rear end parts onto the Insight rear end or of sustituting the Civic rear end for the Insight rear end.

In either case, modification of the existing Insight would be considerable and might involve restyling the Insight rear fenders/skirts if the Civic wheel track could not be shrunk. Finding room to accomodate the rear end differential and motor might require a good bit of frame and sheet metal work in addition to finding or building some kind of structure upon which it could be supported.

This would be a very ambitious project and is way beyond what I am ready to take on at this time. Thank you for your suggestion.