What are the benefits and drawbacks of trikes?

Here, I am specifically asking about motorized trikes like these:




http://tanommotors.com/wp-content/uploads/2014/11/tanom-tc3-main.jpg

  1. Are there any benefits to a conventional trike (1 wheel in the front, 2 in the back) compared to a reverse trike (2 wheels in the front, 1 in the back)? I know that instability while turning at speed is a major drawback of conventional trikes but I’m wondering if they have any benefits.
  2. Compared to a conventional 4 wheel car, what are the benefits and drawbacks of an enclosed reverse trike?

Enclosed trike:
Explore Randall Johnston

3) How about a reverse trike compared to a motorbike?

benifits?

uh…you don’t need a kickstand?

cons?

while I like some of the 3 wheeled car type ones, the three wheeled bike thing (can am) will get you beat up by real bikers.

Talked to an owner of a 2 in front 1 in back recently at the gas pumps.
She bragged about the 38 mpg she gets.
Didn’t have the heart to point at my Prius and say the truth: 48 mpg on that trip from NYC to D.C…fully loaded with equipment cases…

Hell, a Prius might even be “cooler” too.

One manufacturing advantage of three wheelers in the U.S. is that they only have to meet motorcycle safety and emission requirements, not those for cars. Elio motors is planning on exploiting this, but I’ll believe it when I see one on the road.

Aging population.

A good way for folks to keep doing what they like to do with their family, their friends, and on their own.

  1. Instability isn’t that much of an issue with triked motorcycles, mainly because many of those riding them have moved from two-wheels to three because of their age or for medical reasons, and they don’t ride as aggressive as they used to. Stability isn’t an issue very often. But they are a lot more work to get them through a corner. A bit more upper body strength is a requirement especially if you want to ride aggressively.
    Where they really shine is the confidence they give the rider on wet roads. It takes a fairly confident motorcycle rider to stay ahead of a trike on wet roads, keeping in mind the two bikes are similar makes.

  2. Can’t help you there.

  3. A reverse trike, such as a Spyder, is almost as much work steering as a conventional trike. Both types require a lot more effort going through corners, whereas the two-wheel motorcycle requires very little effort. Just a bit of body English.
    What you have to consider with the Spyder, is that they have a very high repair record.

What do you want in a trike? Comfort, reliability, protection from the elements?

no it won’t.

the difference is a trike is still a fun, open-air experience, while the Prius is about as engaging a drive as a fucking forklift.

Don’t two wheel bikes get triple digit MPG figures quite easily? How could anyone think 38mpg on a bike is anything other than awful?

That Can AM thing looks ridiculous, like a riding lawn mower. I’d rather drive a forklift.

I’m more curious about the driving dynamics of a front wheel drive reverse trike, like that Elio motors. Occasionally I see on craigslist trike conversions where someone has grafted a motorcycle rear end onto the front of a Buick Regal and it looks like a hell of a lot of fun.

Bikes generally make far more power per cc than cars. That brings the mileage down.

And have a ton more aerodynamic drag.

But a lot less frontal area.

Is that only because they go at a higher RPM? Going at a higher RPM increases the marginal cost of a mile?

The reason I’ve heard for having higher RPM than cars is higher performance. What is meant by performance here?

Typically, what percentage of the bike’s weight is the engine?

What aspect of the bike causes the most drag?

Would this get the drag back down to car level?


Lighter weight than 4 wheeled car, partly due to MC vs. car safety and emission standards.

Potentially very high performance. Can drift in corners with nearly the power/weight ratio of a 2W motorcycle.

As well as lower barrier to entry for a manufacturer, most places allow “home made” motorcycles to legally take to the road, so these can be built as garage projects. The Chromed example from the OP is based on a VW rear end, for example.

Low slung trikes can be quite stable, especially the tadpole configuration. (two front, one back wheel). Taller trikes may not be able to take corners nearly as fast as a two wheeled motorcycle. Think Tim Conway tipping over on a child’s tricycle. They are stable when stopped, in parking lots, etc. which is where some people struggle to keep a two wheeler greasy side down.

One downside is that one wheel runs in the grease stripe in the middle of the traffic lane. This can be a real concern on wet roads, especially when it just starts raining. There can be more debris there leading to more flats as well. Sidecar motorcycle rigs avoid this via asymmetry, which also provides radically asymmetric steering response.

Having two wheels at the front is much more stable, especially when cornering. Compare the Morgan cars with the Reliant Robin.

all else equal (which it rarely is, but work with me here) running at a higher RPM for a given power output increases pumping losses, reducing engine efficiency. it’s why a 6.2 liter, 450 horsepower Corvette can get 30 mpg highway; running in top gear drops the engine RPM where it’s barely loping over idle.

it really depends on the type of motorcycle. Nobody would accuse most Harley-Davidsons of being set up for performance. In the sport bike world, they usually go for small-displacement, high-revving (and fast revving) engines for insane acceleration. on the order of a Honda CBR600RR, which has a 0.6 liter 4-cylinder which makes 100 horsepower at 13,000 rpm.

depends on the bike, and how it’s set up. for a Harley I’d WAG around 1/4 to 1/3, but that’s largely because their engines, primaries, and transmissions are separate. for the Japanese cruisers and other kinds of bikes which have the engine and transmission as one unit, I’d put it at 1/3 to 1/2 the bike’s weight.

the rider.

  1. The main advantage to a conventional trike is you have more choices since more companies have made them for longer periods of time. The conventional kind can also be slightly more stable in turns than the 2 in front version. Reverse this if we’re talking something with wheels that “lean” a little like the Can-Am does.

Some folks will claim that the conventional ones allow you to pack more stuff easier for seriously long trips but if you are making so many long trips for it to really matter, you probably went with a side-car (you can seriously pack the shit out of those) or the more normal 4-wheeled people-cages. Or just learned to live with less.

  1. No experience worth mentioning with the critters.

  2. For 99% of the riders out there its a toss-up. The nice thing with some reverse trikes (back to that Can-Am again) is that its slightly easier to switch back and forth to/from. I know a lot of people who bought normal trikes with the idea of having that for questionable weather and long-assed trips and a regular 2 wheel bike for around town. Almost all end up just running one and not using the other at all. Even in best cases, they do handle different enough to put you into a wall if you get lazy or dumb.

The best I ever owned was about 80mpg around town from a 250cc Yamaha; something that small for someone my size is around town and some really short trips so I can’t really say what it could/would have done flat-out highway - I suspect not very much more. My biggest Harley will take me 1000 miles in 24 hours (and I have the Iron Butt certificate to prove it) but it only gets say 35 around town and in traffic and say 55 or a bit more highway. Another Harley I have probably gets me a little less from a smaller and lighter bike but ----- forget the laws of Pennsylvania; it will almost defy the laws of physics. Its basically a race bike that passes inspection.

Your mileage will vary but for the most part bigger and heavier means more gas through the tank. Think of something 250cc as a Prius or Geo, something 500cc as a Ford Escort and something big like a Harley or GoldWing as a caddy or H2 — you want that big and that level of comfort and options, expect to pay for it at the pump.

yep. I have two bikes, a V-Star 250 (probably the same one you’re talking about) and a Harley Dyna Switchback. The 250 gets me about 70-80 mpg, the Dyna about 40.

and no, the V-Star 250 is not meant for the highway; I didn’t even dare take it on one. the fastest I’ve had it up to was about 63 mph and it sounded like I was using every last horsepower it had to do so. The Dyna effortlessly gets up to 80 with power to spare. as well it should, what with an engine 6+ times larger :wink:

Well, I’m not a motorcycle guy, but several of my older brothers and their friends were (both street and dirt) and their opinion of conventional trikes was nothing short of considering them all to be total deathtraps!** A generation or two later and I don’t think that opinion has really changed much, which is why they never got popular at all.

You cannot counter-steer a trike, so they don’t turn so much as, well, flip over. When ATVs first came out in the 80s they originally made three-wheelers because they were cheaper and it seemed like they were more suited to kids (like a tricycle). Several deaths and/or paralyzing accidents and multi-million dollar lawsuits later they were all but banned in favor of conventional four-wheeled ones.

Just sayin’… :smiley:

oh, and a motorcycle isn’t?