104 mph self peddled bicycle

We want to see the prototype. Have you built one?

I know you can gear to that speed on paper ,but it would Take a lot of Horse Power

Does it involve a 70 tooth front chainring?

thine82 said:

how could you get more horse power out of your legs when it is based on a 30 rpm? cogi..

scotto ..
have you tried to figure this out and thats why you said a 70 tooth chain ring?

http://www.windmission.dk/workshop/BonusTUrbine.pdf
page thirteen explains how it kinda has to go on.. and then...

Magnetic Induction Bike Lights (Mod)

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No I haven't tried figuring it out because I'm not really interested in trying to pedal that fast or even attain those speeds on my motorized bicycles. I can tell you I've done 62mph riding down the road from Convict Lake on my mtn. bike with a 52tooth front chainring and 10tooth rear. This was in mild prep for running the Kamakazi Downhill at Mammoth Mountain at the Norba Finals in 1990. I think John Tomac who won it that year was running a 61tooth front chainring so I just figure a 70tooth front could get you a fairly high top speed............on a DOWNHILL! That's all.

thine82 said:

i am currently trying to find people or the parts to put this thing together. i have the math all worked out. just need the peices now..

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Oh i gotta see this, show us your 'math' seeing your being so open about it all...

I'm sure the faired recumbent riders would love to se it too seing they can't get past 85mph with all their aero aids and muscle power.

KiM

The only math I am interested in seeing is:

The calculated drag coficeiants at 104mph. (using an upright or recumbent

You cant fool the laws of fluid dynamics.....
the gearing ratios are the easy part.
good luck....google Sam Whittingham. for a little help.

thine82 said:

but i want someone to be able to build a cassette crank that goes from smaller to bigger .. then into the gearbox or transmission.. dont know what it would be .. then build the box with all the stuff in it ..

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I think Thuds your man hes good at building boxes with stuff in it. (wheres the tongue sticking out emotion dammit... )

thine82 said:

how could you get more horse power out of your legs when it is based on a 30 rpm? cogi..

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Quoted from here: Human Powered

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Pedal power uses the most powerful muscles in the body: the quads, hamstrings, and calves. When pedaling in a circular motion at sixty to eighty revolutions per minute, with the use of toe clips, almost every muscle in the human legs can be used to make energy. Ninety-five percent of the exertion put into pedal power is converted into energy. The average rider at a continuous road speed of twelve miles per hour can produce a quarter horsepower (Wilson 1977).

The average, fit, adult rider can produce only 1/10hp when cycling at a continuous 12mph.

Only a top cycling athlete can produce about 1/4 hp - and this is
only for short bursts before overheating - not continuously, and this was confirmed during the Man Powered flights for the Kremer challenge in about 1981.

" I too have read "Bicycling Science" by Wilson 1977, and I think that someone has perhaps mistaken continuous power with peak power. At the end of the day we are just machines, and if you stress us too much we will break sooner."

Ken Boak <[email protected]>
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Well, start with a NuVinci N360 shifting hub.

Product Description
NuVinci Internally Geared Hubs

* CVP (Continuously Variable Planetary) drivetrain technology with an infinite number of ratios
* Simple twist controller enables easy, continuous ratio adjustments while pedaling
* No missed gears, hesitation or noise
* Includes CruiseController shifter
* Comes disc ready, Roller cam adapter available as spare part.
* Recommended gear ratio is 2 to 1 (ex. 36/18)
* Freewheel not included
* Hub's shift drive fits behind dropout for clean installation
* Shifter's cable has quick clip on and off system to allow for simple flat repair

Item Specifications
Weight 2450g (5.4 pounds)
Intended Use Road
Hub Drilling 32spokes
Rear Axle Type 10x1
Cassette Body Type Threaded, Standard
Hub/Brake Compatibility 6-Bolt Disc
Rear Hub Spacing 135mm

Ratio Range 360% Nominal
(0.5 Underdrive to 1.8 Overdrive)
Shifting Variable Twist Grip, 3/4 Turn

Sprockets 17-22 Tooth Supported (standard 9-spline, not included)
Sprocket Ratio 1.8:1 Minimum (17/31, 18/33, 19/35, 20/36, 21/38, 2/40, larger chainrings can be used without exception)

~$360.

At least that way you still use 100% of the input power even while shifting.
Then slap on a front derailer with 3 huge chainrings.

Regardless though, a 1/4 HP in short max pedal bursts isn't going to propel a wheeled vehicle with a human at the speeds you are talking on this planet I don't think ;-}

thine82 said:

because you guys are awesome i will fill you in quickly.. i always have these random ideas..lol... well i thought how about it.. and i did some looking and found that wind mills use a change over process that makes 30 to 40 rpms to about 1500 rpms. so i started looking it up and did the math.. i belive it will have to be 44 teeth to three teeth.. or 44 to nine.. but there is basically five drive sprockets and yes the back tire counts as one kinda.. i will have to load some pics or posts of the pages that i did my research on. but i want someone to be able to build a cassette crank that goes from smaller to bigger .. then into the gearbox or transmission.. dont know what it would be .. then build the box with all the stuff in it .. once sent to the back wheel which might need a different cassette also on it.. i am unsure of that as of now. the regular gearing would still be on the mountain bike in the new cassettes so you could get rolling then as you start moving is when you could change to the other gears so it would haul azz... i talked to a few people and they said it is very possiable.. what do you guys think? just a tinkering idea once again cuz i dont have the means to build this stuff.. well i could order and pay ALOT to do it but i dont wanna do that just yet..

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I forgot too mention, there is not or ever will be a 3 tooth bicycle sprocket, the smallest I know of is 8 tooth. And a 70t front chainring would prolly be scraping the ground. Conventional bicycle chains and gearing will not get you there (72-104mph) without a 90 degree descent.

thine82 said:

.. i am still think about this gear box though..

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The one with stuff in it? can you elaborate on what stuff is in it please, this will allow ThudSTeR time to order in necessary components, if of course you decided he is the one you commission to build the gearbox, with stuff in it...

Might also be useful if we could be let in on the "math" that will get this beast of a bicycle to 104mph, seeing nobody else in the world has managed to do it on flat ground with pedal power alone, until now of course if only theoretically with your numbers and design... Wish you well in your endeavor ** subscribed**

KiM

p.s Can you hear that sound Thud? that's the breaking of world records buddy ...:: crosses fingers:: you get the job building this gearbox with stuff in it ;-P

mmm.. this thread made my morning.

Did you hear that loud boom when that bike passed a few seconds ago,,,,









Gearing for a high speed is a reasonable goal ,but now we need the HP TO TURN THE FIRST GEAR IN THE SET
what is that stuck in the side of that truck???lol

corgi1 said:

Did you hear that loud boom when that bike passed a few seconds ago,,,,

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Just assumed it was thine82 hamstrings letting go from the bone as he pushed the bike to 104mph :-|

KiM

EDiT: while you recover from this minor setback thine82, we had an idea, well actually i must give credit to ThudSTeR ... perpetual motion overdrive for the gearbox with stuff in it!! what ya think? thine82 I mean, heck! why stop at just doing 104mph?!?! Lets smash those pesky laws of thermodynamics once and for all thine82

You need to take a physics class