--- In cvtcontinuouslyvariabletransm@y..., kamilozun wrote:
>As to "too much
> seperation", this is my feeling only. If you say Audi CVT is
> proven as efficiency and lifetime, I have nothing to
> say. But as you know, every rotating mass tends to
> move away with a tremendous force (centrifugal force),
> so do these chain belts, when they are in turning
> cycle (around the pulleys), than the system has to stop
> this inertia, and make it go straight some time, and
> than again .....



This is no different than how chains on motorcycles operate.  Those
chains hold up, so why can't the CVT chain hold up?



Troy

http://www.eyeforfuelcells.com/ReportDisplay.asp?ReportID=887

Thank you for message! I was mistaken about Prius Transmission. I got
mistaken while reading some less accurate articles about Prius. But
after your message I decided to search for more accurate information.
I think the best article is:
  http://www.howstuffworks.com/hybrid-car9.htm

So you are correct. Prius doesn't have a belt/pulley CVT.

It's another CVT concept. I should call it the electric CVT. This
means that mechanical energy is converted into electrical energy and
again back to mechanical energy.

Using a planetary gear set, the engine power is splited into two
parts:
-the first part goes to wheels.
-The second part goes to the generator.

     The electricity produced by the generator will be converted and
go to the electric motor. The electric motor is directly connected to
the wheels.

So, as you see, part of the engine power is converted like:
   mechanical->electrical-electrical->mechanical

Many trains are powered by diesel engines. But these diesel engines
are conneccted to electric generators. The electricity produced is
used on the electric motors of the wheels.

   mechanical->electrical-electrical->mechanical

This type of electric transmission is also used on submarines, etc.
But the Prius system is more efficient -because *only part* of the
engine energy is converted to electricity. Using the planetary gear
set, for example, 50% is converted by the «electric-CVT» and 50% goes
directly to wheels.

As you say, this system spares a belt CVT.
However you know that every energy conversion has losses.
So you could say: -but Prius is very efficient!
Ok. Some reasons for Prius efficiency are:
-computer operates petrol engine strictly on it's efficient ranges.
-If the conditions aren't favourable to the engine, then the engine
is shut-off, and the electric motor is used solely.
-Prius has a very efficient engine.

Conclusion: Prius has no belt/pulley CVT. It has a «electric-CVT».
The engine power is split by a planetary gear set and it's computer
controled.

Thank you again for your pertinent message!

P.S.: By the way, if you wish to compare Honda Insight with Toyota
Prius you should see: http://www.insightcentral.net/prius.html
Honda Insight egroups discussion list:
  http://www.egroups.com/group/honda-insight

--- In cvtcontinuouslyvariabletransm@y..., "electric_troy"
<electric_troy@y...> wrote:
> The Toyota Prius gas-electric hybrid has that kind of CVT.  It uses
a
> standard automatic transmission, but instead of clutches to freeze
> gears in position, the Prius CVT uses 2 motors and an engine.  The
> motors act as variable clutches to spin the internal gears at
varying
> rates... thereby changing the gear ratio between engine and wheels.
>
>
>
>
> Troy

In my opinion, CVT is the ideal transmission concept. Since the first
car was built many types of CVT were invented. One CVT type is the
belt/pulley. That's the most common. Most people don't like the
belt/pulley CVT because they remember that in the DAF-car (in the
sixties) wasn't very reliable. But I'm convinced that the latest
belt/pulley CVT are quite reliable. I advise you to take a look on
the 7th message of this forum: «Audi A4 170Hp CVT comes with a four-
year, 50,000-mile warranty». I never had any belt/pulley CVT car. But
a friend who has a Fiat Punto CVT told me that the transmission never
gave any problems.

--- In cvtcontinuouslyvariabletransm@y..., "electric_troy"
<electric_troy@y...> wrote:
> let me introduce myself. I'm Troy Heagy and I drive a Honda Insight
> that gets 70mpg (actually, I have 84 life average).  Reason I'm
here:
>
> I'm wondering how CVT holds up over the long haul?  My father
advised
> me to stay away from the belt/pulley CVT because "they are nothing
but
> trouble."  Frankly, I don't believe that, so I decided to do
> some research.
>
> For those who have had their CVTs (any model) for 100,000+ miles...
> how did the CVT hold up?
>
>
>
> Troy :-)
>
> P.S. What other models besides Honda Civic HX have had CVT?

Hello Troy,

Welcome to the CVT club.
I hope you enjoy it.
Please take a look at the Bookmarks and add some if you wish.
I think it's better to set the membership options in
[Edit My Membership] to «Individual emails» in the «Message
Delivery», so that you can receive messages on your e-mailbox.

Thank you,
Vitor


--- In cvtcontinuouslyvariabletransm@y..., "electric_troy"
<electric_troy@y...> wrote:
> let me introduce myself. I'm Troy Heagy and I drive a Honda Insight
> that gets 70mpg (actually, I have 84 life average).  Reason I'm
here:
>
> I'm wondering how CVT holds up over the long haul?  My father
advised
> me to stay away from the belt/pulley CVT because "they are nothing
but
> trouble."  Frankly, I don't believe that, so I decided to do
> some research.
>
> For those who have had their CVTs (any model) for 100,000+ miles...
> how did the CVT hold up?
>
>
>
> Troy :-)
>
> P.S. What other models besides Honda Civic HX have had CVT?

--- In cvtcontinuouslyvariabletransm@y..., baratavitor wrote:
> But I not so happy to see that all these CVTs are
> friction dependent. Do you understand? <br><br>I would be
> happier if these car makers would try to investigate new
> CVTs which would not depend on friction to transmit
> forces. The ideal CVT shall have such a mechanism, that
> it could transmit power by means of normal contact
> forces (such as two engaged gears). I hope someone
> invents such a CVT: it is needed everywhere.


The Toyota Prius gas-electric hybrid has that kind of CVT.  It uses a
standard automatic transmission, but instead of clutches to freeze
gears in position, the Prius CVT uses 2 motors and an engine.  The
motors act as variable clutches to spin the internal gears at varying
rates... thereby changing the gear ratio between engine and wheels.




Troy

let me introduce myself. I'm Troy Heagy and I drive a Honda Insight
that gets 70mpg (actually, I have 84 life average).  Reason I'm here:

I'm wondering how CVT holds up over the long haul?  My father advised
me to stay away from the belt/pulley CVT because "they are nothing but
trouble."  Frankly, I don't believe that, so I decided to do
some research.

For those who have had their CVTs (any model) for 100,000+ miles...
how did the CVT hold up?



Troy :-)

P.S. What other models besides Honda Civic HX have had CVT?

Hi «uncchighroller»!
Welcome to this club!
Well, sincerly, I don't know how much HP can you pull from a civic
hx. Anyway be carefull not to exceed the CVT transmission power
capacity.
I advice you to take a look to message 4 of this forum.
Thanks,
Vitor

--- In cvtcontinuouslyvariabletransm@y..., "uncchighroller"
<uncchighroller@y...> wrote:
> Does anyone have any idea of what the max HP you can pull from a
> civic hx with a cvt transmission is? Supercharger, turbo,
> nitrous, ...?  I own a 1998 civic hx with a cvt transmission and
love
> it, but it would be nice to get a some more horses and torque.
Thanks

I own a 1998 honda civic HX with the automatic cvt transmission.
I was wondering if anyone has any idea of what the max horse
power is that you can pull from a cvt transmission.
Supercharger, turbo, nitrous,... are any of these offered for this
make of car?  Thanks.

Does anyone have any idea of what the max HP you can pull from a
civic hx with a cvt transmission is? Supercharger, turbo,
nitrous, ...?  I own a 1998 civic hx with a cvt transmission and love
it, but it would be nice to get a some more horses and torque.  Thanks

1-There are lots of friction-belt CVTs. <br>(ex:
HondaCVT, AudiCVT, etc)<br><br>2-There are lots of
friction-roller CVTs. <br>(ex:
<a href=http://www.torotrak.com/
target=new>http://www.torotrak.com/</a>)<br><br>3-There are lots of variable
displacement hidrostatic
CVTs<br>(ex:
<a href=http://www.off-road.com/dirtbike/aug2000/rick/2001trx500fa/index2.html
target=new>http://www.off-road.com/dirtbike/aug2000/rick/2001trx500fa/index2.htm\
l</a>)<br><br>4-There are lots of rectified variable reciprocating
CVTs<br>(ex:
<a href=http://es.epa.gov/ncerqa_abstracts/sbir/other/pp/fitz.html
target=new>http://es.epa.gov/ncerqa_abstracts/sbir/other/pp/fitz.html</a> ;<br>
<a
href=http://164.195.100.11/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1\
&u=/netahtml/srchnum.htm&r=1&f=G&l=50&s1=
target=new>http://164.195.100.11/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PA\
LL&p=1&u=/n
etahtml/srchnum.htm&r=1&f=G&l=50&s1=</a>'5,951,424'.WKU.&OS=PN/5,951,424&RS=PN/5\
,951,424)<br> - - - - - - - - -<br>All the previous systems
provide infinite ratios. <br>Unfortunately none of these
CVT systems is as as simple, reliable as cheap as two
engaged gears.<br> - - - - - - - - -<br>Some inventors
claim having discovered the positive engagement,
continuously variable transmission, that does not rely on
friction, or hydraulic, or ratcheting:
(<a href=http://www.cvtsystems.com, target=new>http://www.cvtsystems.com,</a> <a
href=http://www.fti-cvt.com/, target=new>http://www.fti-cvt.com/,</a>
<a href=http://www.revolutionindustries.com/
target=new>http://www.revolutionindustries.com/</a>)<br><br>Other people are
very sure that it's impossible to
invent a positive engagement, continuously variable
transmission, that does not rely on friction, or hydraulic, or
ratcheting: (<a href=http://draco.acs.uci.edu/rbfaq/FAQ/148.html
target=new>http://draco.acs.uci.edu/rbfaq/FAQ/148.html</a>)

I do not think (I'm absolutely sure) there can be
a CVT that can transmit force in an engaged style,
without the aid of friction (this type of transmission
would not be a CVT, it will be against the definition
of CVT, CVT means Continuously Variable, unlimited
number of engaged gears), so there can be 18 or 21 or 32
step transmission, like that on the bicycles chain &
sprockets, but not CVT.<br>When it comes to CVT, best
available today, as you know is Variable Diameter Pulley
Sets and Special Belts.<br><br>Another one I have
thought is a Rubber Disc (tyre size) and a Rubber Wheel
driving it at the end of a shaft. You pick up the torque
at the shaft on Rubber Disc Centre, (more similar to
old time Record Players Turntable) . The Vespa wheel
size input starts turning the Disc from the outside
and gradually moves through the center as a function
of desired torque or rev.<br><br>As to "too much
seperation", this is my feeling only. If you say Audi CVT is
proven as efficiency and lifetime, I have nothing to
say. But as you know, every rotating mass tends to
move away with a tremendous force (centrifugal force),
so do these chain belts, when they are in turning
cycle (around the pulleys), than the system has to stop
this inertia, and make it go straight some time, and
than again .....

So the controler will increase the pressure on
the pulleys as function of the measured traction on
the belt. As you know, the transmission may be
subjected to very sudden subit increases on torque. These
instantaneous torque rising may be because engine torque
instant increase or because unexpected road conditions.
So the overall efficiency is highly dependent upon
the quick response of the pulley hidraulic clamping.
<br>For instance, if a car wheel hits a stone, the torque
rises instantanously. The sensors should be able to
detect it quick enougth to increase pulleys clamping oil
pressure and minimize sliping. I feel high performance
hidraulics will be of great importance on avoiding
sliping.<br>If the hidraulic system isn't able to react quickly
then sliping will occur reducing belt life. Also, the
control of presure as funcion torque is essential to
reduce exessive power consumption.<br><br>Audi says it's
CVT will survive for long time: Tests by Audi show
less than 1mm wear on the chain in 300 thousand
kilometres of driving. Dont't forget it's 220-bhp
five-valve, aluminum design, 3.0-liter V-6, peak torque of
221 lb.-ft. raather than Civic's 160 hp.<br><br>I
don't know how this is possible, as «contact to the
pulley cones are on points rather than a surface». I
agree that Honda CVT has more contact area.<br><br>I
don't understand what you mean by «too much seperation
may be at high rev's»<br><br>About the efficiency:
<br> 1-Acceleration and consumption are even better
than the manual transmission! :<br><br>Acceleration
0-100km/h:<br> Audi CVT=8.1s Audi manual=8.2s Audi_5_aut=9.4s
<br><br>Fuel consumption (litre/100km):<br> Audi CVT=9.7 Audi
manual=9.9 Audi_5_aut=10.6<br><br> 2-It's certified as a
'Ultra Low-Emission Vehicle'<br><br>Do you think it is
impossible to invent a CVT that could transmit force in an
engaged style, not than using friction?

I agree with you, we need just "enough" friction,
not "too much" friction between the belt and the
pulley halves, for more efficiency. Torque Sensors
(electronic) and actuators (electro-hydraulic)are essential to
keep the pressure just 2-3 percent above the slip
threshold value (this function has to be programmed in the
EPROMS of CPU, othervise if system waits until the slip
starts, to increase the pressure (so to increase
friction), this is not practical. I THINK HONDA SYSTEM WORKS
THIS WAY .<br>As to the chain type AUDI CVT: I do not
think it will survive too long. All metal first (steel
compared to Honda's Aluminum compression noduls) and
contact to the pulley cones are on points rather than a
surface, and too much seperation may be at high rev's (bec
of centrifugal force). Do you have any idea about
the efficiency levels of this type ?<br>thanks, see
you later.

Friction (Ex.V belt) CVTs are a very ancient
concept. In 1886, the first CVT was built by Daimler and
Benz, two German automotive engineers. Their design was
based on a rubber V-belt that would ride between two
shallow angle cones and has remained relatively unchanged
for the past century. <br><br>I agree that today
these friction-CVTs have to much electronics and are to
much complicated. In my opinion the main reason is
because it's concept depends on friction. Electronics
aply precise hidraulic clamping on the pulley to
generate enough friction to avoid sliping, but not
exessive, because it would unnecessaryly increase fuel
consumtion.<br><br>So greater complexity is because the power is
transmited only-by-friction between Belt and pulleys. The
friction force is tangent to contacting
bodies.<br><br>Automakers should resarch a CVT concept that would not
depend upon friction. The CVT should transmit power by
perpendicular-compression forces, (such as two engaged gears): -note: the
force should be perpendicular to contact surfaces, not
tangent. <br><br>Generaly complexity is the price to pay
in case of using friction to transmit power
efficiently.<br><br>It isn't necessary any electronics/hidraulics to use
two engaged gears on a manual transmission. Such a
CVT concept that transmit power by perpendicular
forces wouldn't require electronics to control and
guarantee enough friction. Simpler and reliable. But such
CVT isn't invented yet. Some people say such CVT is
impossible:
<br><a href=http://draco.acs.uci.edu/rbfaq/FAQ/148.html
target=new>http://draco.acs.uci.edu/rbfaq/FAQ/148.html</a><br>Thank you.

Audi CVT uses a 220-bhp five-valve, aluminum
design, 3.0-liter V-6, peak torque of 221
lb.-ft.<br>(certified as Ultra Low-Emission Vehicles) This
transmission's greater advantage is by far it's both fuel
mileage and tailpipe emissions. Tests by Audi show less
than 1mm wear on the chain in 300 thousand kilometres
of driving. Permanent<br>all-wheel-drive CVT A4 and
A6 models will come on year
2002<br><a href=http://www.thecarconnection.com/index.asp?article=3902
target=new>http://www.thecarconnection.com/index.asp?article=3902</a><br><a
href=http://www.sae.org/automag/techbriefs_01-00/03.htm
target=new>http://www.sae.org/automag/techbriefs_01-00/03.htm</a><br><br>Nowaday\
s car makers are starting to use more CVTs and so
research it<br><br>Mitsubishi has joined Japan's CVT race
with its own transmissions, produced at the Kyoto
Plant. It's the Cedia Model with Direct-Injection. The
Dutch company VDT supplies the push-type steel belt.
The ratios ranging from 2.319: to 0.445:1.
<br><a href=http://www.sae.org/automag/globalview_08-00/03.htm
target=new>http://www.sae.org/automag/globalview_08-00/03.htm</a><br><br>CVT for
MGF: Rover worked with transmission
specialist ZFST of Belgium to develop the
CVT:<br><a href=http://www.sae.org/automag/techbriefs_10-99/08.htm
target=new>http://www.sae.org/automag/techbriefs_10-99/08.htm</a><br><br>General
Motor is reseaching similar CVT as you may see
on:
<a href=http://www.canadiandriver.com/articles/jk/at_010508.htm
target=new>http://www.canadiandriver.com/articles/jk/at_010508.htm</a><br><br>On
the end of the previous site you may also see
another type of CVT: The Honda hydraulic CVT which is
only available on it's Rubicon ATV. More info on the
13th link of this club's links page.<br><br>Tractors
use HYDROSTATIC CVTs made of Variable displacement
pumps/motors (up to 270 HP):
<a href=http://www.agcocorp.com/home.asp?IntPage=OEMSales
target=new>http://www.agcocorp.com/home.asp?IntPage=OEMSales</a><br><br>A more
efficient hydrostatic
CVT:<br><a href=http://www.sae.org/ohmag/toptech/01.htm
target=new>http://www.sae.org/ohmag/toptech/01.htm</a><br><br>Nissan, for
instance, recently developed its Hyper
CVT-M6, which was the first CVT developed for worldwide
use with 2.0-liter and larger engines allowing
20-percent fuel
economy.<br><a
href=http://www.fortunecity.com/silverstone/lancia/58/technical_school/gearbox/t\
ech_gear.htm#Hyper
target=new>http://www.fortunecity.com/silverstone/lancia/58/technical_school/gea\
rbox/tech_g
ear.htm#Hyper</a>
CVT<br><a href=http://www.nissan.co.jp/COMPASS/TECH/CVT/frame6.htm
target=new>http://www.nissan.co.jp/COMPASS/TECH/CVT/frame6.htm</a><br>Also used
on a minivan
(Serena):<br><a href=http://www.sae.org/automag/globalview_10-99/10.htm
target=new>http://www.sae.org/automag/globalview_10-99/10.htm</a><br><br>Anyway
in 1995 the 800 hp Williams Formula One tested a
by a CVT similar to Honda-CVT, as you may se on the
12th message of this CVT-club. See the middle of the
following
pages:<br><a href=http://www.f1rogues.com/articles/article_6.htm
target=new>http://www.f1rogues.com/articles/article_6.htm</a><br><a
href=http://www.ritzsite.demon.nl/DAF/DAF_cars_p17.htm
target=new>http://www.ritzsite.demon.nl/DAF/DAF_cars_p17.htm</a><br><br>And is
seems Ferrary is looking towards a 900hp
Formula
One-CVT:<br><a href=http://f1rumors.net/archive/2001/06/06.html
target=new>http://f1rumors.net/archive/2001/06/06.html</a><br><br>At the same
time, Ford seems to research a CVT with
no belt. ". Two bell shaped discs face each other
with barrel-shaped rollers between the discs. (It can
handle the torque of engines up to 7.3 litres in
displacement.) It requires a specialy developed lubricant to
reduce slipping. Read more on the middle of the
following page:
<br><a href=http://www.canadiandriver.com/articles/jk/at_010919.htm
target=new>http://www.canadiandriver.com/articles/jk/at_010919.htm</a><br>This
CVT is like the
<a href=http://www.torotrak.com/ target=new>http://www.torotrak.com/</a><br

Thank you very much for the interesting link, it
has very good information. So, I added it to the
links section. (Please feel free to add more
interesting CVT links.)<br><br>If wou are improving a
friction CVT I think you should see the links option on
this club: click on links than go to the 11th link
(www.deccdrive.com). I think this friction cvt has no centrifugal
force problems.<br><br>You said you prefer tension
belt, rather than compression: Audi new CVT uses the
belt in tension, rather than compression. Uses
multi-disc clutch and lightweight magnesium case. It's a
link-type chain with 1025-links, 1.4-in.-wide, 3.7-lb
weight. The pulleys clamp the chain contacting with it's
side 75 pairs of link pins. Max.ratio=12.7:1 You may
see on:
<br><br><a
href=http://www.roadandtrack.com/RoadAndTrack/technical/1201_audis_multitronic_c\
vt.html
target=new>http://www.roadandtrack.com/RoadAndTrack/technical/1201_audis_multitr\
onic_cvt.ht
ml</a><br><br>Did you know Audi's new Multitronic
CVT?<br><a
href=http://www.audi.com/com/en/company/company_perspective/technology/multitron\
ic.jsp
target=new>http://www.audi.com/com/en/company/company_perspective/technology/mul\
titronic.js
p</a><br>Audi-CVT is better than the Audi-MANUAL version both in
fuel consumption (9.7 litre / 100km - 9.9 litre /
100km) and also in <br><br>accelaration 0-60 mph (8.1
sec - 8.2 sec)
see:<br><a
href=http://www.fortunecity.com/silverstone/lancia/58/technical_school/gearbox/t\
ech_gear.htm#Hyper
target=new>http://www.fortunecity.com/silverstone/lancia/58/technical_school/gea\
rbox/tech_g
ear.htm#Hyper</a> CVT<br><br>Honda installed a CVT in its 1996
Civic HX. EPA rated at 35 mpg in the city and 41 mpg on
the highway, the Civic was the first successful
attempt at bringing CVT technology to the American car
buyer. Comparison Audi/Honda different
belts:<br><a href=http://www.luk-korbmacher.de/Autos/an7.htm
target=new>http://www.luk-korbmacher.de/Autos/an7.htm</a><br><br>Audi CVT uses a
220-bhp five-valve, aluminum design,
3.0-liter V-6, peak torque of 221 lb.-ft.<br>(certified as
Ultra Low-Emission Vehicles) This transmission's
greater advantage is by far it's both fuel mileage and
tailpipe emissions. Tests by Audi show less than 1mm wear
on the chain in 300 thousand kilometres of driving.
Permanent<br>all-wheel-drive CVT A4 and A6 models will come on year
2002<br><a href=http://www.thecarconnection.com/index.asp?article=3902
target=new>http://www.thecarconnection.com/index.asp?article=3902</a><br><a
href=http://www.sae.org/automag/techbriefs_01-00/03.htm
target=new>http://www.sae.org/automag/techbriefs_01-00/03.htm</a>

HONDA is the best CVT I've ever seen (I've tried
it): <a href=http://asia.vtec.net/article/mmt/
target=new>http://asia.vtec.net/article/mmt/</a> but still, it
seemed too complicated for me. Too much electronics,
compression belts (quite intricate), and expensive too (they
add up almost a thousand USD to the price if you want
CVT).<br>Technically, I'm still in search of a cheaper, cost effective,
efficient CVT (compression type belt that makes HONDA
expensive, because there will be too much friction when you
use Conventional Pulley Set and a Conventional Belt,
especially in seperation during the cycle. Therefore I
concentrate on Special Pulley Set and Conventional Belt.
Another thing: HONDA CVT has problems when it comes to
high rev's, centrifugal force effects efficiency)

About CVT racing Cars:<br><br>It's important to
test mechanical systems in competition because
competition motivates developement, and sponsors finance
it.<br><br>Here are some examples of racing CVT
vehicles.<br><br>In 1993 the Formula One racing Team Williams tested
a CVT on their Formula One and was unsurprisingly 2
a lap seconds faster than the sophisticated
semi-automatic transmissions. Obviously that CVT was faster
because: the engine revs were always kept optimal (=max
power) but the effective gear ratio increased
progressively with speed form low to high». And this was only
the first try, which proves, once again, that CVT is
the ideal car transmission. Unfortunately FIA banned
it, which stalled further usefull sponsored
research.<br>You may find it on the middle of the following
article:<br><a href=http://www.f1rogues.com/articles/article_6.htm
target=new>http://www.f1rogues.com/articles/article_6.htm</a><br><br>On my
prevoius message I sent you a link to 1967
DAF-CVT-Formula-3 car :
<a href=http://www.ritzsite.demon.nl/DAF/DAF_cars_p17.htm
target=new>http://www.ritzsite.demon.nl/DAF/DAF_cars_p17.htm</a><br><br>CVT is
also used on SAE Mini Baja vehicles
competitions:
<a href=http://dilbert.cen.uiuc.edu/soc/sae/baja/cars.html
target=new>http://dilbert.cen.uiuc.edu/soc/sae/baja/cars.html</a><br><br>There
are also races for those small motorcycles with
automatic transmission, called scooters. They use CVTs:
<a href=http://www.gilera-cup.de/ target=new>http://www.gilera-cup.de/</a>
<br><br>Vitor.

Wow, those links are definitely useful. It's
interesting to see the difference between the CVT system of
Honda versus that of Audi. I think Honda needs to get
on the ball with higher horsepower CVTs. Then again,
Honda Civics are supposed to be fuel economical
cars.<br><br>Right now, the latest Civics are offering the CVT
version with 117 horsepower. I've heard that the older
versions could not handle a lot of horsepower because it
would decrease the life of the belt. I don't know if
that is true with the new Civics.<br><br>Also, have
you heard of anyone racing a car with a CVT? If you
know anything about racing CVTs let me
know.<br><br>Thanks!

Dear Lenclud Etienne,<br>Welgome to the CVT
club.<br>Please feel free to express your opinion and ideas about
any subject on continuously variable transmissions.
Also, feel free to invite other friends to this new CVT
club. This new club will be made by it's members, and
for it's members. I hope it's usefull for you
too.<br>Best regards,<br>Vitor

Thank you for the invitation!<br>Bets regards<br><br>Lenclud Etienne

Hi,<br>Here are some interesting links:<br><br>Quite complete
information:<br><a
href=http://www.fortunecity.com/silverstone/lancia/58/technical_school/gearbox/t\
ech_gear.htm
target=new>http://www.fortunecity.com/silverstone/lancia/58/technical_school/gea\
rbox/tech_g
ear.htm</a><br><br>Audi multitronic
cvt:<br><a
href=http://www.roadandtrack.com/RoadAndTrack/technical/1201_audis_multitronic_c\
vt.html
target=new>http://www.roadandtrack.com/RoadAndTrack/technical/1201_audis_multitr\
onic_cvt.ht
ml</a><br><br>Comparison Audi/Honda (different
belts):<br><a href=http://www.luk-korbmacher.de/Autos/an7.htm
target=new>http://www.luk-korbmacher.de/Autos/an7.htm</a><br><br>CVT/sports:<br>\
<a href=http://www.ritzsite.demon.nl/DAF/DAF_cars_p17.htm
target=new>http://www.ritzsite.demon.nl/DAF/DAF_cars_p17.htm</a><br><br>DAF CVT
1967:<br><a href=http://www.ritzsite.demon.nl/DAF/DAF_cars_p3.htm
target=new>http://www.ritzsite.demon.nl/DAF/DAF_cars_p3.htm</a><br><a
href=http://www.ritzsite.demon.nl/DAF/DAF_cars_p9.htm
target=new>http://www.ritzsite.demon.nl/DAF/DAF_cars_p9.htm</a><br><a
href=http://www.ritzsite.demon.nl/DAF/DAF_cars_p10.htm
target=new>http://www.ritzsite.demon.nl/DAF/DAF_cars_p10.htm</a><br><a
href=http://www.classic-daf.nl/indexb.html
target=new>http://www.classic-daf.nl/indexb.html</a><br><br>Regards,<br>Vitor

Hi Jim,<br><br>Thanks for your email.<br>I am
aware of Audi CVT. It shares the same idea os Honda
CVT: Two conical pulleys and V belt. The main
difference is the beld. Both belts are metalic. But Audi's
belt is almost a chain belt and it's a pull belt
instead of Honda's push-belt. Audi says it's durable
enoughfor big engines. The Audi A4 170Hp CVT comes with a
four-year, 50,000-mile warranty. <br>At least according to a
article, the Audi CVT is 0.1 seconds faster 0-60 than the
Audi-manual-transm, and gets better gas mileage (0.5 MPG). This means
that the transmission is more efficient I believe, so
Audi seems to have done a very good job. At least
better than Honda. :) <br><br>You may find additional
Audi-CVT information on the following sites:<br><br>form
Audiworld:<br><a href=http://www.a4.org/news/100699.html
target=new>http://www.a4.org/news/100699.html</a><br><br>MSNBC
News.<br><a href=http://stacks.msnbc.com/news/665417.asp?cp1=1
target=new>http://stacks.msnbc.com/news/665417.asp?cp1=1</a><br><br>To learn
about
CVT:<br><a
href=http://www.edmunds.com/ownership/techcenter/articles/45104/article.html
target=new>http://www.edmunds.com/ownership/techcenter/articles/45104/article.ht\
ml</a><br><br>Another friction CVT is being developed: www.torotrak.com
. But the web site is down.<br><br>Anyway I think
automobiles and industry need an innovative concept of CVT
rather than friction transmissions.<br><br>Best
regards,<br>Vitor.

Hi Vitor,<br><br> I don't know too much about the
mechanics of CVTs. I just know the basics. I do believe
that in the U.S. the CVTs will eventually gain
popularity (at least over conventional automatics). Audi is
putting out a car this year with a CVT for the first time
(I'm pretty sure). I'm sure the CVT technology in
Audis is much different than that in the Hondas because
Audis are usually much faster cars. Do you know
anything about this?<br><br>Later,<br>Jim

Hi streak790!<br>It's good to receive your
email!<br>I'm not a Honda Civic owner. I dont't have a car at
all. But I'm very interessted on CVTs. It's very good
that Honda has this CVT car. Unfortunately other car
makers aren't wise enough to see that CVT is the best
transmission. Also most people don't prefer it because they
ignore it's avantages. In my country (Portugal) there is
a wrong idea that automatics have less driving
pleasure and control. Most people don't even distinguish a
common automatic transmission (with 4 or 5 fixed ratios)
from a CVT (infinite ratios). But I've heard that many
Car Makers (Ford Torotrak, etc) are developing new
CVTs so they could transmit more power. This makes me
a bit happy because it means that the CVT is
incresing. But I not so happy to see that all these CVTs are
friction dependent. Do you understand? <br><br>I would be
happier if these car makers would try to investigate new
CVTs which would not depend on friction to transmit
forces. The ideal CVT shall have such a mechanism, that
it could transmit power by means of normal contact
forces (such as two engaged gears). I hope someone
invents such a CVT: it is needed everywhere.<br><br>Most
car CVTs have two pulleys and a metalic belt. The
power is transmited by friction between the metalic
belt and the pulleys. So it's not so easy to get as hi
efficiency as two engaged gears. On the other hand, two
engaged gears transmit power by normal forces. Slipping
is impossible. On the other hand, the CVT belt
requires high compressing forces to minimize slipping
which dissipate energy.<br><br>Do you know torotrak
CVT? It's also friction dependent. Instead of a a belt
and conical pulleys, the power is transmited by
friction between two solid rolers. This also requires hi
pressure to minimize slipping and so limited to small
torque transmission.<br><br>Anyway I would prefer to
have a Civic CVT than other manual or automatic
transmission car (if I could afford a car). In my opinion CVT
is the best transmission. But someone should invent
a non-friction CVT. I don't think it's
impossible.<br><br>What's your opinion.<br><br>vitor<br><br>.

I've been away for a while, but now I'm back. I
set up a club for Honda Civic owners with CVTs (and
for owners with regular transmissions too). There is
only one trim level (the HX) on the Civic line that
offers this transmission. The ride is very smooth and so
far I haven't heard of any major problems with the
Honda CVT. What kind of CVTs do you guys have? Let's
get a discussion going on this board again!

Sorry for my delay.<br>All kind of CVT. Anyway,
it would be interesting to compare advantages and
disadvantages of the existing models. We should also talk about
new inventions or ideas for better
CVTs.<br>Thanks<br>vitor

what Kind of CVT and their uses are you intrested in?<br>thankyou<br>jeffery

Welcome to the Yahoo! Message Board for CVT Continuously Variable Transm