joe99

In Australia, there is a TV program called "New Inventors", each episode of which features 3 new inventions which are assessed by panel of "experts".

Last night's show included a bike in which the rotating pedals and cranks are replaced by a pair of levers.

The show can be found at
https://www.abc.net.au/tv/newinventors/txt/s2055118.htm
and there is a video clip of the inventor explaining and demonstrating the "Leverbike".

How many times has this been invented before?

DanPT

Well there is the staircycle

https://www.staircycle.com/bmoviesb.html

edp773

The cranks are still there, they are just shorter and mounted below the dangerous seat post.

joe99

Point taken

I guess a more accurate description would be "the pedals have been replaced by a pair of levers and connecting rods."

tsl

There was also the "transbar" bike by Alenax. Even came in road and MTB versions. My LBS has a couple of them hanging on the wall.

maddyfish

How does this improve upon regular bikes?

Velo Dog

I've seen at least two or three over the years, and it's one of those things that makes you blink and say, "Huh?" You need rotating motion at the drive wheel, and on most bikes you have rotation at the crank. I don't see any advantage in starting with linear motion and converting it. It's got to add weight to the system, and while you don't really pull up on the pedals much as you ride a conventional bike (that's a myth, disproven many times in tests), you do carry the pedalling effort a little more than 180 degrees. With the levers, seems like you'd lose that small additional input.

tsl

They don't, which is why they don't survive long in the marketplace.

The claimed advantage is a straight downstroke as opposed to pedaling circles. Allegedly this is better for the leg joints. There were also claimed but disproven power improvements. (They're difficult to stand and pedal and clipless gives you power in the full circle.)

All this is offset by increases in weight, complexity, cost and reliance on proprietary repair parts.

But for the inventor, it gets attention, then later, you can claim it was forced out of the marketplace by conspiracy in the same way the mythical 100 mpg carburetor was. Just before the UFOs landed.

edzo

100mph carb is not a myth


it exists. but it is not practical. it takes 10 minutes to go from 0 to 30mph

nick burns

1839 - Kirkpatrick Macmillan

Cyclaholic

That's not my experience, I pull up hard to the point where I can't ride platform pedals without a conscious effort to not pull up.

Can you cite references to scientifically valid, independent tests that you refer to?

Mchaz

What's more ergonomic than walking? Nothing...that's why I use...

The Treadmill Bike!

It's really the next generation of 2-wheeled transit.

Cyclaholic

WOW! a machine that allows you to actually walk down the street! imagine that.

TomatoSue

I watched this segment on the New Inventors, one of the points the inventor made was that it eliminated the need for a bicycle seat.

In the clip they showed it didn't look very aerodynamic.

geebee

So you get to stand for several hours on a long ride?
No resting on the seat on downhills, no tucking.
A 25mph head wind would be fun.
Real practical, not.

Cyclaholic, I have the same issue with platforms they feel weird and inefficient as I have to keep reminding my self not to lift my feet off.

dynaryder

CommuterRun

^^Now that's just flat funny, there. He looks like he's having some kind of seizure.

Now, please excuse me while I clean up the coffee...and blow it out of my sinuses.

hotbike

I just did a Google search for the word "bicycle"

and I customized the search by searching News with dates from 1860 to 1870.

Aparently treadle drive was around back then and there was a patent dispute.

https://query.nytimes.com/mem/archive...B4668382679FDE


invented or re-invented?

Note: the article is in pdf

eubi

I'll chime in for Velo Dog.

I don't remember the sources, but I remember at least three tests I read back in the 70's and 80's that proved that VERY FEW world class racers pull up on their pedals. I believe at least one of them was published in Cycling Science.

I also remember an interview with Greg Lemond, and he said he pushed down on the pedals, and pulled back (like scraping mud off your foot), but did not pull up.

I'm not trying to start any arguments. If it works for you and others, great.

v1k1ng1001

This isn't the same idea at all, but I always wanted one of these as a kid so I thought I'd post the picture.

Little Darwin

I'll have to see if I can find a source on this as well.

I seem to recall specifically that for the fastest cyclists, there was "some" power on the upstroke, but it was very little more than removing the weight from the pedals. It was considered trivial when compared to the power of the downstroke.

Obviously, this would be enough to make someone used to riding clipless have issues on platforms, but it doesn't necessarily mean that the power of the upstroke is significant for world class riders...

What happens in an unusual situation does not necessary repreasent relative strength... When I operate the brake in my car with my left foot I just about lauinch myself through the windshield, but this does not mean that my left foot is significantly stronger than my right foot...



I do not dismiss that there may be some that have significant power in their upstroke, but I have read that for most, the power is minimal, other than removing the resistance to the downstroke.

Mtbnomore

I rode something like this at the Tour de Fat.

v1k1ng1001

Yeah, but it says "For guys 8,9,10 years old who really know how to ride." I missed my window.

Doug5150

I have one bike with clipless pedals, and another city/errand bike without.
When riding the city bike I do tend to lift my feet up off the pedals during the upstroke, enough that they tend to change position a bit.

I don't think I do this enough to contribute much power during typical riding, but it does happen without concious effort.
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Doug5150

It's my belief that a system that allows for variable leg-stroke would be at least very much more comfortable to use than conventional pedals, and I intent to build one at some point in the future. It would also be heavier, but that doesn't mean it wouldn't be more useful. A single-speed bike is lighter than the same bike with a geared hub, but most adult bikes bought for recreation (in first-world countries at least) have gears, because people think that the ability to match the pedaling load somewhat to their preferred exertion level is worth hauling around a couple more pounds of metal for.

If you consider the leg extensions people use while jogging, they start out taking rather long strides, then take shorter strides as they get tired. They take moderate strides on level ground, tend to take shorter strides going uphill, and do "lunges" up stairs, skipping one or more stairs. They do not use the same leg extensions all the time, because it's not comfortable or natural to do so. The fact that many bicycles have gears does not address the problem of the same leg extension always being used.

A bicycle with conventional cranks forces you to use the same exact leg extensions all the time. Most casual riders don't tweak their crank lengths to perfection, cranks don't come in a wide-enough variety to even suit the general population and even if you could make adjustable-length cranks that could change length on the fly, you'd still have the problem of the leg-extension to seat distance.

I would also point out that many of these lever-systems are not levers at all but treadles, which are just fixed by connecting rods to a conventional crank setup, and don't benefit from variable-length pedal strokes at all. The only advantage these can claim is a pedal surface that doesn't move fore-and-aft as much as a pedal on conventional cranks would.
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