A Cycling & bikes forum. CycleBanter.com

Go Back   Home » CycleBanter.com forum » rec.bicycles » General
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

"Liquid Drive" bike prototype at auction



 
 
Thread Tools Display Modes
  #21  
Old November 28th 03, 06:27 AM
Carl Fogel
external usenet poster
 
Posts: n/a
Default "Liquid Drive" bike prototype at auction

Tom Sherman wrote in message ...
Rick Onanian wrote:

... How about a bike shaped like a cow? That would be cool....


See http://www.chicagotraveler.com/cows/235.jpg

Tom Sherman - Planet Earth


Dear Tom,

Thank you for a wonderful picture. My only
regret is that it looks as if the handlebars
are not the horns.

Moo!

Carl Fogel
Ads
  #22  
Old November 28th 03, 08:38 AM
Carl Fogel
external usenet poster
 
Posts: n/a
Default "Liquid Drive" bike prototype at auction

A Muzi wrote in message ...
Carl Fogel wrote:

-snip-
Here's a stray question to emphasize the depth of my
ignorance: are there fixed-gear tandems? If so, do
they use a different gear--higher or lower--than
either rider would normally use?

-snip-

Traditionally, the only competitive tandem event is on the
track. Gearing used to be 46x16. (I haven't kept up with that.)


Dear Andrew,

I hope that you enjoy my naive questions
as much as I enjoy your answers. Honest
to God, they're racing fixed gear tandems
around tracks? I love it.

I have a vision of two tandems warily
jockeying for position on a banked wooden
oval, doing semi-trackstands and eyeing
each other like gunfighters in a bad
Western.

I suppose that it's not like this really,
but please don't spoil my fantasy.

Thanks,

Carl Fogel
  #23  
Old November 28th 03, 09:01 AM
Ryan Cousineau
external usenet poster
 
Posts: n/a
Default "Liquid Drive" bike prototype at auction

In article ,
(Chalo) wrote:

It looks like the fella behind this CVT hydraulic bike is trying to
raise some capital by selling off his prototype:

http://cgi.ebay.com/ws/eBayISAPI.dll...tem=3641257316

http://www.powerengine.com

It seems like a cool artifact, if not particularly practical.

I know this particular bike has come up for discussion before, with a
certain amount of pooh-poohing of the general concept. Since this
thing surfaced again, I've been reflecting on what hypothetical
advantages a hydraulically driven bike could have over a chain driven
bike, which might offset the drawbacks of what is almost certainly a
heavier, lossier, and more expensive system than chain drive. So far
I've come up with:

1) True continuously variable transmission ratio, which this bike has

Some people insist we want CVT, but hydraulically driven vehicles have
always had it available and are still rather uncommon. For instance,
Hondamatic motorcycles never caught on, though their system seemed to
work as intended. I'm unconvinced that it's really as desirable as
its proponents say.


The original CB750A and CM450A Hondamatics were not CVTs. They used
fluid torque converters instead of a plate clutch (just like any
automatic car), and 2-speed transmissions. I'm not even sure if they had
automatic shifting.

http://100megsfree4.com/honda/h0700/amatic.htm

You mean this Hondamatic?

http://he.honda.ca/motorcycles/model...RX500FA_pf.asp

It's not a motorcycle, but it is interesting. A hydraulic CVT on an ATV.

I think the argument for a hydraulic CVT on a utility ATV is much
stronger than the one for the same drivetrain on a motorcycle, and much,
much stronger than the argument for a bike.

How did CVT become associated with the HPV community, when human power
seems to tolerate a wide range of RPM?


It's a logical extension: like all underpowered engines, humans benefit
from lots of gearing choices. This led people to believe that continuous
gearing would be even better than a mere 18 or 27 or 30 speeds.

4) Possibly less regular maintenance and system wear

Many hydraulically powered machines work around the clock for years
between breakdowns in the hydraulic systems. (I am reminded of
various forklifts I've worked with, whose batteries always seemed to
be troublesome but whose hydraulics were seemingly invincible.)
Hydraulic systems by their nature run in a lubricant bath, and much of
the mechanical wear in them occurs to the fluid.

I am sure that not every cyclist would be willing to give up a
noticeable amount of efficiency to have a service interval measured in
years, but some certainly would if the cost were not offensive.


I think the problem is that you can get similar durability and better
efficiency and weight by going to a shaft drive. That's why most
performance-oriented applications (cars) use shafts as a compromise
system when chain or gear drive setups don't have what it takes.

The possibilities outrun my ability to imagine good uses for them-- so
much about the bikes we know is just corollary to the chain drive,
that it's difficult to imagine what a "normal" bike would be like in
the absence of one. The high wheeler is what you get when you assume
that a bike's cranks will drive its axle directly, and the diamond
frame with derailleurs is what you get when you assume the use of a
chain drive. If you don't assume either of those things, then what?

I suppose the answer to that will have to await another feasible
alternative, if there is one.

Chalo Colina


That's just the trick. Chain is so good, it defeats all other options.
You use belts or enclosures if the filth bothers you, but that's it.
Maybe some recumbents would benefit from a long, stiff shaft drive,
given their ludicrous chain issues.


--
Ryan Cousineau, http://www.sfu.ca/~rcousine
President, Fabrizio Mazzoleni Fan Club
  #26  
Old November 28th 03, 07:32 PM
Carl Fogel
external usenet poster
 
Posts: n/a
Default "Liquid Drive" bike prototype at auction

Ryan Cousineau wrote in message ...

[massive snip]

That's just the trick. Chain is so good, it defeats all other options.
You use belts or enclosures if the filth bothers you, but that's it.
Maybe some recumbents would benefit from a long, stiff shaft drive,
given their ludicrous chain issues.


Dear Ryan,

I love ludicrous issues.

I occasionally see recumbents wobbling along on
my local bicycle path, but have never inspected
a dead one's anatomy--possibly there is a secret
recumbent graveyard.

Is the length of the chain-run a problem? That is,
are longer chains less efficient, harder to shift,
more prone to wear?

Or is it the peculiar arrangements rather than the
mere length?

Are recumbent chain problems worse than tandem chain
problems?

Any concrete answers or even wild speculation will
be appreciated, since I'd hate to shoot such rare
creatures just to dissect their chain anatomies.
I can recall only a single tandem sighting in fifteen
years and fear that they may be extinct in these parts.

J.J. Audubon
  #27  
Old November 28th 03, 09:30 PM
Tom Sherman
external usenet poster
 
Posts: n/a
Default Recumbent bikes (was: "Liquid Drive" bike prototype at auction)


Carl Fogel wrote:

Ryan Cousineau wrote in message ...

[massive snip]

That's just the trick. Chain is so good, it defeats all other options.
You use belts or enclosures if the filth bothers you, but that's it.
Maybe some recumbents would benefit from a long, stiff shaft drive,
given their ludicrous chain issues.


Dear Ryan,

I love ludicrous issues.

I occasionally see recumbents wobbling along on
my local bicycle path, but have never inspected
a dead one's anatomy--possibly there is a secret
recumbent graveyard.


Recumbent owners keep their bikes forever.

There are no low quality/low price recumbents (equivalent to discount
store bikes) and the majority of commercially produced recumbents were
made in the last 10 years. Therefore, unlike upright bicycles, one is
unlikely to find recumbents in dumpsters, along the curb, at police
auctions of abandoned bikes, etc.

Is the length of the chain-run a problem? That is,
are longer chains less efficient, harder to shift,
more prone to wear?


Chain wear mainly occurs when the tension (power) side of the chain is
bent around the drive cog(s). Since recumbent chains are generally much
longer, they typically last much longer (assuming similar conditions of
use). I suspect that the cost per unit distance for recumbent chains
does not differ significantly from upright chains.

Shifting quality on a recumbent depends primarily on the quality of
derailleurs, shifters, cassettes and chainrings used. An advantage of
RWD recumbents is that the chain angle is lessened when the driven cog
does not line up with the driving chainring. One can get away with using
cross-gears much more so than on an upright. On the downside, recumbent
shifter cable runs are typically longer and more convoluted than those
of uprights are, and this can impact shifting in a negative manner.

Small drivewheel bicycles that use larger than normal chainrings
generally have poorer shifting quality - this is true of both recumbents
and small wheel uprights. I had 73/52 chainrings on a bike I used to own
[1] and front shifting was not the best. This is compounded by the lack
of large chainrings with ramps and pins. My current bike uses a clever
step-up jackshaft to avoid this problem and has excellent from shifting.
[2]

Or is it the peculiar arrangements rather than the
mere length?


For reasons of aerodynamics (reduced frontal area) and power production
(angle formed by the seatback, seat base and BB) unfaired performance
recumbents have the BB located higher than the seat. A direct chain run
from the BB to the rear sprocket(s) would pass through the rider.
Therefore, some combination of mid-drive, jackshaft, chain idlers, chain
tensioners and chain tubes is required for chain routing.

Any concrete answers or even wild speculation will
be appreciated, since I'd hate to shoot such rare
creatures just to dissect their chain anatomies.
I can recall only a single tandem sighting in fifteen
years and fear that they may be extinct in these parts.

J.J. Audubon


[1] http://www.ihpva.org/incoming/2001/wbone2.jpg
[2] http://www.ihpva.org/incoming/2002/sunset/Sunset001.jpg

Tom Sherman - Planet Earth
  #28  
Old November 28th 03, 11:19 PM
Rick Onanian
external usenet poster
 
Posts: n/a
Default "Liquid Drive" bike prototype at auction

On Wed, 26 Nov 2003 23:35:44 -0600, Tom Sherman
wrote:
Rick Onanian wrote:
... How about a bike shaped like a cow? That would be cool....


See http://www.chicagotraveler.com/cows/235.jpg


That's a trike. Close enough...where can I get one?

Tom Sherman - Planet Earth

--
Rick "Moooooooo" Onanian
  #29  
Old November 28th 03, 11:55 PM
Tom Sherman
external usenet poster
 
Posts: n/a
Default "Liquid Drive" bike prototype at auction


Rick Onanian wrote:

On Wed, 26 Nov 2003 23:35:44 -0600, Tom Sherman
wrote:
Rick Onanian wrote:
... How about a bike shaped like a cow? That would be cool....


See http://www.chicagotraveler.com/cows/235.jpg


That's a trike. Close enough...where can I get one?

Tom Sherman - Planet Earth

--
Rick "Moooooooo" Onanian


Unfortunately, all the cows were sold four years ago.
http://www.chicagotraveler.com/cows_on_parade.htm

Tom Sherman - Planet Earth
 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
buying my first road bike Tanya Quinn General 28 June 17th 10 10:42 AM
How old were you when you got your first really nice bike? Brink General 43 November 13th 03 11:49 AM
my new bike Marian Rosenberg General 5 October 19th 03 03:00 PM
Single Speed Cruiser vs. Mountain/All Terrain Bike for Commuting? Luigi de Guzman General 2 August 21st 03 05:02 PM


All times are GMT +1. The time now is 06:22 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.
Copyright 2004-2018 CycleBanter.com.
The comments are property of their posters.