(Wind) RESISTANCE IS FUTILE

safe

1 GW
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Dec 22, 2006
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"Bicycle Of Reduced Girth"

:idea: "You will become one with the B.O.R.G."

Let's set up a little thought experiment to see if I can get you to join the B.O.R.G.

Let's assume:

http://www.kreuzotter.de/english/espeed.htm

:arrow: Bicycle One: Road Bike "hands on the tops".

:arrow: Bicycle Two: ShortWheelBase Recumbent. (low aerodynamics)

We will assume that we want to carry a top speed of 40 mph on flat land.

Going to the online calculator we get:

Bike One - 1600 Watts - 40 mph

Bike Two - 805 Watts - 40 mph

Difference - 795 Watts


It does not matter if you are in a "recumbent" or a "road racer" the point of this is that low aerodynamics is such a dominating factor that to not join the B.O.R.G. is futile.

Pedaling is futile... you must join the B.O.R.G...

(well unless the laws say you have to pedal :wink: )

Electric power is best used as part of the B.O.R.G...


homer2.gif
 
nice

You are right about the futility of peddling, I love to peddle and I like the exericse it helps keep the lbs off but at 25-30mph on my bike you aint doing shit really, you look at the watts up meter and your input is nothing!! I suppose its better than not peddling but not much and you are totally right, you would prob get as far for the power if you dropped the bars right down, kicked your feet back and streamlined.

I still love to peddle and I am fitter and lighter for it but as far as adding to my speed at 25-30, it doesn't do a lot, you forget just how much the motor is doing it all for you! my bike makes me feel like Lance Armstrong everyday, in reality I am just human :wink:

Cheers

Knoxie
 
For really fast bikes, the crazy idea of running the chainring to a generator instead of to the wheel might make sense. You could contribute power (by recharging the batteries) regardless of the speed.

You could even pedal going downhill. Something like a rewound geared brushed motor might work. Even a small 250w one would handle more power than my out-of-shape legs could ever supply.
 
What a great idea!! ha ha I would have never thought of that, nice one richard it makes perfect sense!! and to be hones it is a great idea at any speed!

Cheers

Knoxie
 
Right, velectris has a section of their forum dedicated to this idea, design goals was for it to weigh <2kg>90% overall eff. Looks like development is in progress at Lille general engineering school.

http://www.velectris.com/forum/f25-velo-sans-transmission.html

Somehow though, I plan to stick with existing bike drive trains for quite a while. Kinda for the same reason I don't have a bent. Aero's got nothing to do with it, try finding a semi-decent one for a reasonable price - not gonna happen.
 
I hope everyone reads that link... it was very interesting.

Would this qualify as "pedals" on the national electric bike law?

It sort of blurs the line between a motorcycle like "pure" motor powered bike and the multiple input electric bicycle that has to deal with motor torque and wildly oscillating human torque.

I like the idea... makes me go hmmmmmmm.... 8)
 
It's worth getting a copy of the proceedings of the 4th Velomobile Seminar (Assisted Human Powered Vehicles) - there's other interesting stuff in it, besides the exposition on the Chainless Transmission.

http://www.futurebike.ch/FB_Web_WM99/events/wm99/english/e_seminar.html

http://www.ihpva.org/SourceGuide/Library/proceedings.html

http://www.hpva.us/pdf/HPVord.Nov01.pdf
 
safe said:

Would this qualify as "pedals" on the national electric bike law?

You keep looking at the upside of the law, that the glass is half full.

I suppose if it came down to it the law would ultimately need to be tested & a precedent set, but the intent behind the pedal provision is that they must be continuously operable & capable of propelling the bike all on its own without any throttle input. How fast, it don't specify. So unless the genny could make the bike move, the answer is no. It pretty much mandates parallel hybrid.

There is no loop-hole you can dream up that the legislators haven't already considered. Remember, they already went thru this process in the seventies with mopeds & have all the necessary legal remedies in their toolkit. If & when the ebike population with illegal overpowered motors reaches the requisite tipping point, you can look forward to e-bikes follow the same path to requiring registration.

https://web.archive.org/web/2008011...ris.com/forum/f25-velo-sans-transmission.html
https://web.archive.org/web/2007070...SourceGuide/Library/proceedings.html#3rdIHPVA
https://www.hupi.org/HPeJ/0015/SeriesDriveHybridVelomobiles.pdf
 
It's not like there's anything bad about registration. You just need to hook up working blinkers and brake lights, then have it briefly inspected, from what I understand. The electronics gurus here can probably use a breadboard circuit to use the e-brakes' signal to activate a brake light.
 
Series hybrid would meet the letter of the law on the flat if you can pedal between 200~500 watts for a short stint it should move the bike, assuming the motor is not rated so high that it needs more to move.
Should work a treat with Euro specs at 250 watt motors.
Having said that parallel hydrid is more practical and efficient, lots of low torque from the rider.

Knoxie pedalling with noticable input is doable at 40 mph with the correct gearing and bike/trike.

Safe try the figures for a Quest.
 
Geebee said:
Knoxie pedalling with noticable input is doable at 40 mph with the correct gearing and bike/trike.

Safe try the figures for a Quest.

I know... 390 Watts to reach 40 mph... amazing! :wink:
 
If anybody here likes formulas and spreadsheets, this is a decent read:

http://www.recumbents.com/WISIL/Hein/Hpvpaper.htm

"There have been many general debates about whether the extra speed of a faired bike on level-ground and downhill speed makes up for the reduced speed when climbing hills. This paper describes the general terms involved in the tradeoff and concludes with a systematic method that can be used to determine the tradeoff in terms of overall trip time. "


:D
 
On an ebike it would be a win-win situation, as they will have enough speed up hills that the aero benefits would be more than (outweigh? :lol: ) the extra weight.

Croswinds and bike racks are two things I would be concerned about personally, but I definitely want to build at least a 1/4 front fairing to join the 60mph club. 56.5mph on flat ground is the new unfaired speed, so I won't need much help to go another 4mph.
 
Lowell said:
...but I definitely want to build at least a 1/4 front fairing to join the 60mph club. 56.5mph on flat ground is the new unfaired speed, so I won't need much help to go another 4mph.

http://toledo.craigslist.org/mcy/301777544.html

$50 us

Vetter fairing off of 1983 1100 Goldwing complete with lowers and mounting bracket also included chrome rear seat rail

0FfLgV3zYhXEaBsrpf5yiVpRTu87.jpg


:?:
 
fechter said:
For really fast bikes, the crazy idea of running the chainring to a generator instead of to the wheel might make sense. You could contribute power (by recharging the batteries) regardless of the speed.

You could even pedal going downhill. Something like a rewound geared brushed motor might work. Even a small 250w one would handle more power than my out-of-shape legs could ever supply.


Then safe replied, "Would that qualify as pedals under the law?"

I think we should be allowed to do our pedaling at home to recharge the batteries. You can tell the cop, "Officer, I was just at home peddling my generator. I promise."
 
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