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Date: 17 Jun 2007 23:20:08
From: Troll Report
Subject: "Gain Ratio"
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Try as I might, I fail to understand the importance, if any, of the concept
of gain-ratio. I've read http://sheldonbrown.com/gain.html twice over, and
I've researched the relevant discussions on the deja.com archives. Is the
concept of gain-ratio valid, worthy, and applicable, or just a bunch of
[insert expletive] ?
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Date: 19 Jun 2007 21:16:27
From: datakoll
Subject: Re: "Gain Ratio"
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nothings right in flooroda. highest in crime lowest in intelligence.
makes marsielles feel like cambridge.
the feds built intercoastal waterway bridges without movable spans at
80-120' up to clear the occassional large ship? so the climb up with
80-90 pounds of groceries into a 20 mph wind is on a 1/5' grade.
anyway. the standard 10 speed gearing is more for walter mitty racers.
shimano dropped the small gear to a 38 tooth CR for the deore touring
crankset. works great with a 14-32 7 speed plus 34 cog.
still goes 35 behind a UPS truck but beats the wind no problem.
you should see my pedals. I'll look for a camera.
besides. i suggest to people who dabble in cycles that they should be
on the large CR all the time unless they're on the bridge into the
wind and they look at me like I lost a bolt
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Date: 19 Jun 2007 09:42:10
From:
Subject: Re: "Gain Ratio"
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On Jun 19, 12:33 pm, "Sandy" <leu...@frree.fr > wrote:
> Dans le message denews:1182263836.921196.227380@p77g2000hsh.googlegroups.=
com,
> datakoll <datak...@yahoo.com> a r=E9fl=E9chi, et puis a d=E9clar=E9 :
>
> > what good is it? as with most cycle or nuclear weapon modeling issues,
> > fundemental grip is necessary to figure whazzitallmean.IN THE
> > BEGINNING, I had no idea and passed over the subject.
> > Butbutbut deciding to go with less teeth on the smell ring( and
> > screwup the seamless standard shift progessions) for more effective
> > climbing under grocery loads, I guessed hmmmm -1,-2,-3,-4 teeth?
> > dumb. Quantification with the gain method and a %%%% comarison to the
> > prior setup is uhuh rational. 38-44? or was that 43?
>
> Climbing ?
> Florida ?
> Hmmmmmmm.
> Something's not right.
Yep, the Sunshine State-- flat as a pancake. But the winds can make
you wish you were in the Rockies.
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Date: 19 Jun 2007 17:43:58
From: Paul Myron Hobson
Subject: Re: "Gain Ratio"
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> On Jun 19, 12:33 pm, "Sandy" <leu...@frree.fr> wrote:
>> Climbing ?
>> Florida ?
>> Hmmmmmmm.
>> Something's not right.
vellowfellow@gmail.com wrote:
> Yep, the Sunshine State-- flat as a pancake. But the winds can make
> you wish you were in the Rockies.
Florida also has a special type hill. The rest of the country just calls
them "bridges."
\\paul
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Date: 19 Jun 2007 14:37:16
From: datakoll
Subject: Re: "Gain Ratio"
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what good is it? as with most cycle or nuclear weapon modeling issues,
fundemental grip is necessary to figure whazzitallmean.IN THE
BEGINNING, I had no idea and passed over the subject.
Butbutbut deciding to go with less teeth on the smell ring( and
screwup the seamless standard shift progessions) for more effective
climbing under grocery loads, I guessed hmmmm -1,-2,-3,-4 teeth?
dumb. Quantification with the gain method and a %%%% comarison to the
prior setup is uhuh rational. 38-44? or was that 43?
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Date: 19 Jun 2007 18:33:15
From: Sandy
Subject: Re: "Gain Ratio"
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Dans le message de
news:1182263836.921196.227380@p77g2000hsh.googlegroups.com,
datakoll <datakoll@yahoo.com > a réfléchi, et puis a déclaré :
> what good is it? as with most cycle or nuclear weapon modeling issues,
> fundemental grip is necessary to figure whazzitallmean.IN THE
> BEGINNING, I had no idea and passed over the subject.
> Butbutbut deciding to go with less teeth on the smell ring( and
> screwup the seamless standard shift progessions) for more effective
> climbing under grocery loads, I guessed hmmmm -1,-2,-3,-4 teeth?
> dumb. Quantification with the gain method and a %%%% comarison to the
> prior setup is uhuh rational. 38-44? or was that 43?
Climbing ?
Florida ?
Hmmmmmmm.
Something's not right.
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Date: 19 Jun 2007 02:18:53
From: PiledHIgher
Subject: Re: "Gain Ratio"
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On Jun 19, 6:31 pm, Michael Press <rub...@pacbell.net > wrote:
> In article
> <1182181471.764894.107...@j4g2000prf.googlegroups.com>,
> Tom Ace <tom...@gmail.com> wrote:
>
> > Gain ratio is the ratio of pedal force to drive force.
>
> > E.g., in a gear with gain ratio of 5, to drive the
> > bicycle with a force of x requires a force of 5x at
> > the pedal (more pedantically: a pedal force whose
> > component in a direction normal to the crank and
> > normal to the bottom bracket axis is 5x).
>
> > Gain ratio has the elegance of being a pure number (no units).
>
> > Whether it's better than some other measure of gear depends
> > on what you want to do. For gauging the effort required to
> > pedal, it's just the ticket. But if you want to convert
> > crank RPM to speed, development is a more useful measure.
>
> For my own purposes I chart my gears by km/hr @ 90 rpm.
> For communication I call out the cog counts: e.g
> 50/18 (== 32.1 km/hr @ 90 rpm).
>
> --
> Michael Press
But where is the bragging rights in that?
Everyone knows you are a hard man if you tell them that you have a 98"
gear on!
Riding track leads to some interesting stuffing around, people who
will swap a chainring and a cog to get 0.5" more or less.
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Date: 20 Jun 2007 00:40:46
From: Michael Press
Subject: Re: "Gain Ratio"
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In article
<1182244733.540596.55840@a26g2000pre.googlegroups.com >,
PiledHIgher <PiledHigher@gmail.com > wrote:
> On Jun 19, 6:31 pm, Michael Press <rub...@pacbell.net> wrote:
> > In article
> > <1182181471.764894.107...@j4g2000prf.googlegroups.com>,
> > Tom Ace <tom...@gmail.com> wrote:
> >
> > > Gain ratio is the ratio of pedal force to drive force.
> >
> > > E.g., in a gear with gain ratio of 5, to drive the
> > > bicycle with a force of x requires a force of 5x at
> > > the pedal (more pedantically: a pedal force whose
> > > component in a direction normal to the crank and
> > > normal to the bottom bracket axis is 5x).
> >
> > > Gain ratio has the elegance of being a pure number (no units).
> >
> > > Whether it's better than some other measure of gear depends
> > > on what you want to do. For gauging the effort required to
> > > pedal, it's just the ticket. But if you want to convert
> > > crank RPM to speed, development is a more useful measure.
> >
> > For my own purposes I chart my gears by km/hr @ 90 rpm.
> > For communication I call out the cog counts: e.g
> > 50/18 (== 32.1 km/hr @ 90 rpm).
>
> But where is the bragging rights in that?
>
> Everyone knows you are a hard man if you tell them that you have a 98"
> gear on!
>
> Riding track leads to some interesting stuffing around, people who
> will swap a chainring and a cog to get 0.5" more or less.
I like it!
--
Michael Press
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Date: 18 Jun 2007 08:44:31
From: Tom Ace
Subject: Re: "Gain Ratio"
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Gain ratio is the ratio of pedal force to drive force.
E.g., in a gear with gain ratio of 5, to drive the
bicycle with a force of x requires a force of 5x at
the pedal (more pedantically: a pedal force whose
component in a direction normal to the crank and
normal to the bottom bracket axis is 5x).
Gain ratio has the elegance of being a pure number (no units).
Whether it's better than some other measure of gear depends
on what you want to do. For gauging the effort required to
pedal, it's just the ticket. But if you want to convert
crank RPM to speed, development is a more useful measure.
Tom Ace
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Date: 19 Jun 2007 08:31:46
From: Michael Press
Subject: Re: "Gain Ratio"
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In article
<1182181471.764894.107090@j4g2000prf.googlegroups.com >,
Tom Ace <tom239@gmail.com > wrote:
> Gain ratio is the ratio of pedal force to drive force.
>
> E.g., in a gear with gain ratio of 5, to drive the
> bicycle with a force of x requires a force of 5x at
> the pedal (more pedantically: a pedal force whose
> component in a direction normal to the crank and
> normal to the bottom bracket axis is 5x).
>
> Gain ratio has the elegance of being a pure number (no units).
>
> Whether it's better than some other measure of gear depends
> on what you want to do. For gauging the effort required to
> pedal, it's just the ticket. But if you want to convert
> crank RPM to speed, development is a more useful measure.
For my own purposes I chart my gears by km/hr @ 90 rpm.
For communication I call out the cog counts: e.g
50/18 (== 32.1 km/hr @ 90 rpm).
--
Michael Press
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Date: 18 Jun 2007 21:47:26
From: Leo Lichtman
Subject: Re: "Gain Ratio"
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"Tom Ace" wrote: Gain ratio is the ratio of pedal force to drive force.
(clip)
^^^^^^^^^^^^^^^
IOW, it is the reciprocal of mechanical advantage. The only disadvantage I
see is that it is yet another system that people are unfamiliar with and
will be confused by.
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Date: 17 Jun 2007 23:40:47
From: tiborg
Subject: Re: "Gain Ratio"
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On Jun 18, 4:20 pm, Troll Report <trollr...@rt.net > wrote:
> Try as I might, I fail to understand the importance, if any, of the concept
> of gain-ratio. I've readhttp://sheldonbrown.com/gain.htmltwice over, and
> I've researched the relevant discussions on the deja.com archives. Is the
> concept of gain-ratio valid, worthy, and applicable, or just a bunch of
> [insert expletive] ?
Seems like it wouldn't work for elliptical gears, unless you refer to
the number as an instantaneous gain-ratio. However, the fact that it
takes crank size into account makes it a better comparative number
than the other methods mentioned on Sheldon's site.
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Date: 18 Jun 2007 09:08:33
From: Paul Myron Hobson
Subject: Re: "Gain Ratio"
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tiborg wrote:
> On Jun 18, 4:20 pm, Troll Report <trollr...@rt.net> wrote:
>> Try as I might, I fail to understand the importance, if any, of the concept
>> of gain-ratio. I've readhttp://sheldonbrown.com/gain.htmltwice over, and
>> I've researched the relevant discussions on the deja.com archives. Is the
>> concept of gain-ratio valid, worthy, and applicable, or just a bunch of
>> [insert expletive] ?
>
> Seems like it wouldn't work for elliptical gears, unless you refer to
> the number as an instantaneous gain-ratio. However, the fact that it
> takes crank size into account makes it a better comparative number
> than the other methods mentioned on Sheldon's site.
I prefer meters development. Seems practical enough.
The cranks on all of my bikes are 165 mm or 170 mm in length. Not
enough to make a real difference in the gain ratio or be noticed by the
user (me, that is).
\\paul
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Date: 18 Jun 2007 16:40:20
From: Tim McNamara
Subject: Re: "Gain Ratio"
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In article <f5604i$ket$1@news-int2.gatech.edu >,
Paul Myron Hobson <phobson@gatech.edu > wrote:
> tiborg wrote:
> > On Jun 18, 4:20 pm, Troll Report <trollr...@rt.net> wrote:
> >> Try as I might, I fail to understand the importance, if any, of
> >> the concept of gain-ratio. I've
> >> readhttp://sheldonbrown.com/gain.htmltwice over, and I've
> >> researched the relevant discussions on the deja.com archives. Is
> >> the concept of gain-ratio valid, worthy, and applicable, or just a
> >> bunch of [insert expletive] ?
> >
> > Seems like it wouldn't work for elliptical gears, unless you refer
> > to the number as an instantaneous gain-ratio. However, the fact
> > that it takes crank size into account makes it a better comparative
> > number than the other methods mentioned on Sheldon's site.
>
> I prefer meters development. Seems practical enough.
I still use gear inches. Pardon me while I get my knuckles off the
floor and get the cave fires burning before I go out and kill something
for dinner.
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Date: 19 Jun 2007 01:24:19
From: Bill
Subject: Re: "Gain Ratio"
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Tim McNamara wrote:
> In article <f5604i$ket$1@news-int2.gatech.edu>,
> Paul Myron Hobson <phobson@gatech.edu> wrote:
>
>> tiborg wrote:
>>> On Jun 18, 4:20 pm, Troll Report <trollr...@rt.net> wrote:
>>>> Try as I might, I fail to understand the importance, if any, of
>>>> the concept of gain-ratio. I've
>>>> readhttp://sheldonbrown.com/gain.htmltwice over, and I've
>>>> researched the relevant discussions on the deja.com archives. Is
>>>> the concept of gain-ratio valid, worthy, and applicable, or just a
>>>> bunch of [insert expletive] ?
>>> Seems like it wouldn't work for elliptical gears, unless you refer
>>> to the number as an instantaneous gain-ratio. However, the fact
>>> that it takes crank size into account makes it a better comparative
>>> number than the other methods mentioned on Sheldon's site.
>> I prefer meters development. Seems practical enough.
>
> I still use gear inches. Pardon me while I get my knuckles off the
> floor and get the cave fires burning before I go out and kill something
> for dinner.
Why does anybody even care about gain ratio? Just pick a gear that feels
right and pedal. The great thing about legs is that they can't stall
like a car engine. Of course they can't blow up from over-revving
either. If your top and bottom gears are right then all you really have
to worry about is a big gap somewhere in the middle. I have 21 speeds on
all my mountain bikes and a measly 10 speeds on my road bikes.
More speeds? Why?
Bill Baka
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Date: 19 Jun 2007 22:32:18
From: still me
Subject: Re: "Gain Ratio"
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On Tue, 19 Jun 2007 01:24:19 GMT, Bill <bbaka@comcast.net > wrote:
>Why does anybody even care about gain ratio? Just pick a gear that feels
>right and pedal. The great thing about legs is that they can't stall
>like a car engine. Of course they can't blow up from over-revving
>either. If your top and bottom gears are right then all you really have
>to worry about is a big gap somewhere in the middle. I have 21 speeds on
>all my mountain bikes and a measly 10 speeds on my road bikes.
>More speeds? Why?
>Bill Baka
Well, I care because I like to choose freewheels and chainwheels that
give me the overall range I want on a particular bike - that is, a low
enough low and a high enough high. I also like to have relatively
smooth and equal jumps between gears where practical, simply to make
riding more pleasurable - big jumps up are hard to overcome and big
jumps down take me off my pace when I might have kept the speed up
higher without as large a jump down.
I honestly don't care much about the exact ratio once I am on the
road. It's only in "design" that I care.
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Date: 18 Jun 2007 22:19:17
From: still me
Subject: Re: "Gain Ratio"
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On Mon, 18 Jun 2007 16:40:20 -0500, Tim McNamara
<timmcn@bitstream.net > wrote:
>
>I still use gear inches. Pardon me while I get my knuckles off the
>floor and get the cave fires burning before I go out and kill something
>for dinner.
I use gear inches too, because I've done so for years. That means I
know what 100 inches feels like, what 42 inches feels like, and I know
how much of a jump 8 to 10 inches is and that I don't want to get up
to 10 inches, or down below 6 inches, between gears, even on my lowly
12 and 14 speed bikes, if I can avoid it. If nothing else, gear inches
gives you finer gradiation.
But, a more useful question in life is why we worry about the
horsepower a car can produce when in fact horsepower can't even be
measured, we have to measure torque and then we calculate horsepower!
(Or, as they say, "same thing" - pick your favorite. I like torque).
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Date: 18 Jun 2007 19:25:15
From: Paul Myron Hobson
Subject: Re: "Gain Ratio"
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still me wrote:
> On Mon, 18 Jun 2007 16:40:20 -0500, Tim McNamara
> <timmcn@bitstream.net> wrote:
>
>> I still use gear inches. Pardon me while I get my knuckles off the
>> floor and get the cave fires burning before I go out and kill something
>> for dinner.
>
> I use gear inches too, because I've done so for years. That means I
> know what 100 inches feels like, what 42 inches feels like, and I know
> how much of a jump 8 to 10 inches is and that I don't want to get up
> to 10 inches, or down below 6 inches, between gears, even on my lowly
> 12 and 14 speed bikes, if I can avoid it. If nothing else, gear inches
> gives you finer gradiation.
I see your point, but it's not really the case. "Meters" development is
simply the units used in the final calculation. Centimeters and
millimeters could just as easily be used. Similarly, the significant
digits could be carried on further beyond the decimal point.
What it really comes down to: I don't like English units ;)
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