Give Me a Name!

It sounds really technical but just creates a number of questions. Isn't centripetal force the force that moves you around a circular arc? It seems like he is describing the perception of outward force mistermed as centrifugal force. I am not sure that you lean into a corner primarily to use a larger softer surface area of the tire, since people on street bicycles moving at higher speeds do the same thing to turn. If you take a measuring wheel (or any wheel for that matter) and tilt it as you roll the wheel you will see that natural tendency to follow a curve in the direction of the lean. It seems that if you tried to turn without leaning less force is directed into the motorcycle and more is lateral across your body rather than downward through your body (that seems very uncomfortable and potentially dangerous). Also, I am not sure that motorcycles really steer that differently than bicycles, the forces and masses are jsut greater I believe.

Quite right. My error entirely.

Its funny, most people think they know how a bicycle turns, or an automobile turns, but the reality is that it is a lot more complicated is generally supposed.

Leaning is a red herring. Or should I say, weight transfer is a red herring. You can move all over your bike, reach down and pick up a handkerchief off the road if you like...you can still go in a straight line. The bike and rider are in equilibrium. If you countersteer, it results in a true lean of both the bike and rider, a movement around the caster, which results in centripetal force, (towards the inside of the turn) which you have to admit, has to be there if you expect to turn into a curve. If you try to stay upright in the turn (like a lot of newbie passengers and first time bike riders) your bike has to lean further in order to compensate and stay in equilibrium. If you were to lean way over, your body mass will affect the angle so that the bike's wheels will stay more upright. A bike is nothing if not stable and in equilibrium when up to speed!

The lean you see from the side of the road is not really a lean at all...the bike thinks it is upright. The lean it uses for steering is actually very little, most of what you see is just there to compensate for inertia (the mis-named centrifugal force) and you do that by keeping the bike in equilibrium....by leaning it.

This of course results in problematic traction issues.

The tire is shaped like a donut, with a rounded wheel, not a flat one like a car or a truck. So when there is a turn (for whatever reason) more rubber touches the road. As well, the centre rubber is harder for longer wear, and the side rubber is softer and stickier. That how motorcycle tires are made. So if you want more traction, you just have to lean the bike. You don't get much more though, but if you are racing, it becomes kind of useful. If you want to turn, you don't have to lean or transfer your weight at all, just countersteer. The precession will do all the leaning you need.

It is almost impossible to get enough angle on a bike to break its traction before you start hitting frame members, so the only reason I over transfer my weight in a curve is to either keep the wheels more upright on the road (hopefully improving traction a bit and avoiding scraping those frame members), or to compensate for the passenger who is leaning to the high side.

There, not so techical. And I checked it over, used the right terminology this time. I am not making this stuff up. A bike is VERY complicated machine, and it is a product of its environment as much as a fish is a product of his. If you didn't have those gyroscopes of wheels, things would be a LOT different!

So when you ride a bicycle [or motorcycle] no handed why doesn't it continue in a straight line when you lean?

A similar effect is observed by shifting a majority of your weight to one footpeg or the other.

the larger the mass of the cycle, the less the rider can influence changes in direction my shifting his weight. Cruisers have shallower steering angles & are consequently more stable [harder to change direction]

Dual compound tires are a recent innovation, to compensate for the lack of grip, due to the lower temperature & subsequent lower grip of the side wall rubber. There are a range of profiles available ranging from triangular, to nearly flat like a car tire.

"I just can't believe I can't explain something that I know so well."

Your post is still shorter than the wiki you posted on the same subject. I can't imagine why this would be off topic. ga.

Feel better? pretty pictures, nice presentation

you can use the throttle, brakes, the handlebars & your weight to change direction. The geometry & type of suspension; the size, weight & composition of the wheels; speed, available power,surface; wheelbase determine which combination of the possible inputs will be the most effective in changing direction.

yes of course most [throttle & brake excepted]changes of direction are dependent pointing the front wheel in a different direction than the rear wheel [

The bicycle wheel is nice to demonstrate gyroscopic effect, but isn't relevant in the weighting of footpegs, unless the design is now a unicycle.

http://en.wikipedia.org/wiki/Bicycle_and_motorcycle_geometry

thank you.

I see head angle and rake... which must be what was meant by 'headstock rake' and I also see "trail" but that must be what "lead" meant. ??

chris

okay

Well done. Good you put it here!

Except that oops, I made two unforgivable mistakes...when you push forward on the LEFT handlebar, you turn left. Not the right handlebar. doooh. This happens only after you get up to speed. At low speeds, it is the opposite.

Its called counter steering, and it results in a gyroscopic precession which affects the steering geometry.

And I was incorrect in calling it centripital force...the drag or wheel geometry which turns the bike towards the inside of the circle is centripital, (thats how you steer), whereas the force which flings you outwards is centrifugal. (I know, its not really a force...its just inertia, yet the traction pad on the road doesn't care if its a vector, a force, or a virtual force! ) Mea Culpa. So everywhere I used the word "centripital", please replace it with the word "centrifugal". I am glad somebody called me on that! Shows they are reading!

So, it wasn't that I was shy Cris, but rather that I wanted to get my statement out, and fact check later. I stand behind the rest of the "lecture" (rant) though. I should have just let it sit in my out box until I was ready to post.

I'm psychic.. I knew what you meant.

OK, lets play. Rough terrain, no explosives. Mad Max for poor people.

Bets any one?

The pink bit is a "Harmonica Suspension". Thought of it and made drawings of it when I was 8 years old. 50 bloody years ago, on a farm in outback Australia where cars were as rare as hens teeth.

Back then it was part of the seats, childish, I know but that's what I thought how it could work. And by now it's developed into something doable. Want to make some CAD's of it Chris? You seem to have nothing else to do but laze about all the time, so you might as well. I'll send you the drawings I have.

Open source? I don't think so, Ky.

What!!? I'm so busy I don't have time to even answer all the posts on this thread...

send me your pictures when you find them.

cheers,

Chris

no.. the wings are just too short for flight...and lifting down.

Oh MaLaren!

But Oh Potential!

this is the first render of the half-shell.. more of a rudder-able sail.

but it quickly disappeared as the streamlining increased... rev 2.0

but of course you know I have my own designs on roadable aircraft.

"but of course you know" I can't resist a tease

Already exists:

http://www.terrafugia.com

For a name, how about Quadrollette. (Quad roll aye)

For propulsion, how is this for an idea. As you are going with fly by wire control, what about electric hub motors on each wheel, powered by a diesel driven electric generator(alternator). Perhaps "hybrid" in nature. This would give you the acceleration and throttle response without the nasty lag as experienced in drive by wire cars. The Diesel generator would be constant speed and run on demand whilst the Quadrollette would be in essence a LiFePo4 battery electric vehicle. I can't call it a bike, it is perhaps a "Cycle Car" as defined by various government transport departments.

As an electric hybrid vehicle it may be eligible for government funding or concessions. Just a thought, results may vary with individual countries "greenwash" legislation.

Hub steering is a good idea, but use it for both front and rear wheels. Proportional control in relation to the speed of the vehicle. Low speed maneuvering will want a different treatment to highway speeds.

It looks pretty funky all the same.

Name suggest

Kniphe

that took me a minute... lol

but interesting.

quadrollette.... well um.. I don't want to discourage you.. but that isn't really working for me... sorry.

I do like the idea of this being electric.. but I know knothing about that technology... right now I'm busy reinventing the wheel..

Chris-if you go electric, a whole lot of acceleration-oriented restrictions are mooted, because of the inherent weight of the batteries making high accelerations unattainable. I read somewhere that the highest density energy storage based on weight was in deforming rubber, so an hybrid electric/rubber storage system, with serious attention paid to lightening the design wherever possible could wind up giving you respectable performance: or maybe just lithium hydride cells for storage. Focus on weight reduction will allow a range of possibilities, like . . . fun. Smaller wheel diameters and non-leaning suspension geometries look lighter to me, as well.

Hmm, if you are going to reinvent the wheel go all the way and re-invent the power source. I am leaning towards small nuclear fusion generator electric hybrid, never need to stop that way.

Hey Chris how about calling it the razor? It's sleek and doesn't cause much friction.

When you get it all figured out I want one. It looks awesome.

I like that!... or the Crazor... :)

You read my mind that's originally what I was going to put down.

He does that all the time, even over long distances

_{(I have been wearing a lead shield inside my foil hat to try to prevent him from reading my mind. Another trick I have been practicing is to try to think only in pig latin. I don't think Chris can read pig latin.)}

Oy vey! Oyez! oyay esyay Iay ancay! _Snort

Chris, I promised more information on the rotary actuators. http://www.helac.com/actuators/

I delivered. Cheers.

awesome...

The design incorporates limited rotation ability along with a very rugged bearing assembly, and no protrusions like the rack and pinion style rotators.

A low hight McPherson strut with the rotator on the bottom could cover all of the front geometry except the leaning associated with 2 wheeled vehicles. And the only connection would be hydraulic hoses.

That's a nice looking futuristic single passenger automobile AKA Car. However, it is not a motorcycle because it has 4 wheels. A motorcycle has 2 wheels and operates under the gyro principal.

In many jurisdictions, three-wheeled vehicles, especially smaller ones, are also motorcycles, by law [licensing]. Three-wheeled roadgoing vehicles don't typically utilize the gyro effect to any significant degree. Some lean into corners, and others don't.

Having four wheels does usually disqualify vehicles from being licensed as motorcycles, granted.

I thought motorcycle operates much like all other motorized vehicle by use of a engine and either a drive shaft of chain/belt that transfer the power to a wheel which then transfer tha power to the pavement surface. So what does the gyroscopic priciple have to do with how it operates?

Well - it's obvious.

When you turn the steering the gyroscopic reaction tilts the bike - yes?

But "forgotten" is; this tilts the rear wheel (gyroscope) too.

And That Means; the only resolution of that gyroscopic force must be to force the frame 'forward'.

I can't believe you people don't know these things!

I mean, look; this guy stays upright purely by gyro-motor!

He's not moving how ever hard I press that pointy finger, cursor. He is getting nowhere real fast it seems. Is it that I am missing something? Ah, you want me to read!?

I'm out of here, Ky.

To add to what 34.5 said:

It's called precession. To turn a motorcycle at speed, you push on the left handgrip to turn left, right to turn right. The great unwashed think that pushing on the left would make you turn right (which is true at very low speeds) but thanks to precession makes a two wheeler respond just like a gyro.

Hooker

Chris,

Kudos to ya for a beautiful design of a new "vehicle".

But... a motorcycle it ain't. A bike is more than the number of wheels, or the suspension or the steering controls or that it has open seating vrs something with roll up windows.

Let me extrapolate a bit if I may:

My bike (almost) never goes on high speed highways (like US interstates). Even my GPS is set to avoid major highways for trip planning. On the bike I am always on minor highways or back roads even on long distance trips. On those roads, when I have sight distance, a bike can be thought of as an wingless two wheel low level "Flyer" (to steal from the Wright Brothers) rather than an earthbound method to get somewhere. I have control of an axis (lean) that can work to my advantage that is simply a side effect in a four wheeler. I can really power through the road, taking advantage of every inch available and exploiting the advantages that only two wheelers have. I can become one with the machine: I don't have to think about the mechanics or the techniques of manipulating the machine, I just do.

So, while it would be neat to have a machine like the one you've portrayed above, it would have a very different draw and use in my life from my two wheeler.

Hooker

No matter what you call it though, the Crazor is still an awesome machine.

I would sure like to cruze around in one. I think it's a nice piece of work and hope it gets built. It's nice to see someones Idea on paper be brought to life and made a reality, so many don't. Keep the idea alive Chris and build one, or two, I'll take the extra one and do it justice.

I agree, it does look awesome and I'd love to drive it, too.

But that wasn't my point!! It won't "replace" my motorcycle, any more than a personal watercraft would replace a towed ski. They are different experiences. And that is a good thing!!!

Hooker

there is a tiny glimmer of hope...

I don't have your email address... it looks so much cooler as wallpaper. I can send you 2732 x 1536 pixels.. pm me.

Chris

so poetic!

and most people don't understand the relationship between man and machine... you have just captured it...

great stuff.

so um... which is better for your soul... motorcycle or helicopter?

I was wonder why this one wasn't mentioned.

The T-Rex

http://www.youtube.com/watch?v=iluIZqOFYCA

T-Rex is cool... but not an open cockpit design like a bike, snowmobile, or watercraft. (which was one of my criteria) I had a girlfriend a few years ago, and she told me that her "Harley was the best vibrator money can buy."

Chris

I had a girlfriend a few years ago

Well, without any doubt you're an engineer. One might assume this was during your teens ? If otherwise, plaese go and beg a place on the naughty step (it's rather crowded).

not an engineer. yes naughty at times. no not a teenager... 45 then. ^{_{(girlfriend for lack of a better term)}} Proud to be on the naughty world step

chris

Oh look. All my friends are on the step with me.

another interesting vehicle

Chris

I am not a bike rider to begin with. But one that makes no sound seems like a magnet for slow turists in Florida looking for an accident.

this is pretty sick... the Hubless Monster.

The bearing in this looks like a larger version of a bearing user in older design roof turrets. I bought one about 12 years ago. It was made by a company called Kadon (?). And then my 6 in. bearing was $600 plus.

I pondered turning the wheel/rim into the armature of an electric motor

Since it's a flight of fancy, might as well use room temperature super conducting wire & what ever unobtainum sounds like fun :D Which brings up questions of:

How to attach the tire?

How efficient can it be with the less the ideal field shape?

Like this one?

http://www.youtube.com/watch?v=zPSoNfmuBXc

I had thought of it, in principle, years and years ago. Somethings in the air tonight, Ky.

yaeh I trot that one out from time to time, mostly I would get Puzzled dog look [tilts head quizzically]

trick would be how not to increase the unsprung weight

I imagine rim or spokes as winding

lots of cool things that could be done with freq drives, regenerative braking.

on a different note, you won't see any hubless rims on any thing but foo foo choppers, too heavy & a real amount of side play...

The Tron Legacy Bike at Fan Expo in Toronto 2009. Must steer like a Dyson Vacuum Cleaner.

I'm looking forward to it.

No - Dyson's can steer.

What would guess the maximum lean at ? 20⁰

Now ask "why does a flat belt center on a domed pulley?"

Good grief - just as well it's "massless"

(now where is that

)