Trimuter, Trimutor, Trike, Kit car, 3wheeler
 

Don't know if someone has already posted this, so thought I would just throw it into it's own thread. This one is on Ebay.

https://cgi.ebay.com/ebaymotors/ws/eB...m=150016545334

Imagine one of these with a metro drivetrain! :) This one is within 25 miles of my location...waiting for a call back from them to go check it out.

The funny thing about these is they'd get better mileage going backwards! The aero is off by 180 degrees.

I think I'd also prefer 2 wheels up front for better handling.

Looking for a project are you? :)

Always looking & thinking, thankfully I rarely act on the large $ impulses.;)

Went and looked at the trimuter yesterday....it was really neat. It had a datsun 210 rear independent suspension/rear set up (Pumpkin turned backwards). The vehicle was powered by a Honda Goldwing 1100 (not currently installed) and 'belt driven' from the Goldwing transmission to a pulley coming off of the rear.

Rough shape, but all there...was tempting, but didn't move on it.

I think I'd also prefer 2 wheels up front for better handling.:p


pret auto

Speaking of tadpole style trikes, I happened to stop by Arcimoto today while they were allowing somebody to demo their latest prototype.

It looks like a fairly promising design concept with their 3rd gen. prototype, and their next one already under construction showing significant refinement of the spaceframe. I'm looking forward to seeing the production version which they are targeting to sell for about $16,000. That beats the pants off of the Aptera and offers significant refinement over something more spartan like the Bug-E.

it def has the aero issue well in hand.

I've had a few single fr wheel trikes and felt stability was fine.

Actually, if done correctly, the 1-in-front trike can have superior stability. It all depends on a number of factors including center of gravity, front/back weight distribution, track width etc. The Vigillante trike had a theoretical tip over limit of 3.27 g's, meaning it would spin out long before it would flip, and was stable under heavy straight-line braking, even with the wheels all locked up. Here's a link to a top-gear article from 1998:
Vigillante

I disagree with the reverse tadpole design having superior stability for one specific reason: People don't plan to have to hammer the brakes and swerve in an emergency, an action that often generates the highest g-forces to which the reverse design would still be more susceptible to instability and or rollover with all else being equal.

In more technical terms, the distance of the center of gravity to the fulcrum line between the front and rear tires is much shorter with a reverse tadpole under hard braking and turning than it is from the CG to the contact patch of the front wheels on a standard tadpole.

These are forces that one is unlikely to be able to replicate to the same degree under acceleration and would be more expected/planned for as well.

If the theoretical tip-over limit exceeds the maximum g forces the tires can produce, it doesn't matter what you do, it won't rollover. Unless you hit a curb going sideways or something, but that would roll even a Corvette. "With all else being equal" is correct, but only an idiot would put the engine in the front of a reverse tadpole trike. AKA, everything you said I agree with 100% wrt to one of those stupid and dangerous Goldwing trikes.

If you take a look at the article I linked, the designer talks about the stability of the Vigillante, which is an example of a reverse tadpole "done right". He distributed the weight so that under full braking the weight distribution was 33/66 fr/rr leading to a stable condition, even under full wheel lock. Impossible to roll, due to the low/rearward CG, and only able to lift the front wheel very briefly under hard acceleration from a stop. Its very low polar moments of inertia minimized the side-load needed on the front tire for turning.

Thinking about it further, I suppose it could be said that a tadpole "all else being equal" would have better braking/turning stability, but it's really a moot point if either design has a theoretical tip over limit exceeding the tires maximum grip, since in the absence of hitting something that would tip any wheeled vehicle, rollover is not a concern.

As far as performance, under braking a tadpole that distributes 66/33 fr/rr vs. a reverse tadpole that distributed 33/66 fr/rr . . . both should have equal stability.

Under acceleration, the reverse tadpole wins, as it can distribute nearly all of it's weight on the rear wheels. A FWD tadpole would shift the weight away from the drive wheels, and a RWD tadpole that maintained 66/33 fr/rr under braking would never have the traction the reverse tadpole would have.

All great points. That car illustrates very well that despite the theoretical limitations of the reverse tadpole, it is effectively relegated to being a non-issue. On that point, I was clearly splitting hairs. ;)

Your idea for using a Geo metro drive train is a good one I have been thinking of doing this too. I looked at the Geo metro and it would be easy to drop out the front suspension and drive train complete with steering column. build a frame for a trike around it, add a very light highly Aerodynamic body and 100 MPG should be do able