Dear Jobst, Left-Hand Chain-Drive Details

[Carl Fogel]

Dear Jobst,

In a recent email about a bicycle rear-wheel text that you were asked to edit, you mentioned that
you dislike abbreviations like DS and NDS for drive-side and non-drive-side.

When you suggested that right and left were shorter, simpler, and just as good as DS and NDS, I
replied that I'd just seen an odd-looking bike whose chain and gears were on the left.

(I call them gear-side and no-gear-side because my rear wheel is usually upside-down when I'm
looking at it, so right and left are reversed. God knows what we'd call one of the old-style
reversible rear wheels with a large climbing cog on one side and a small high-speed cog on
the other.)

Anyway, here's a site that mentions the odd left-side drive that I saw:

http://www.bmx-test.com/cgi-bin/reviews.cgi?review_id=745

I expect that all my nieces and nephews know this stuff, but we don't seem to get a lot of BMX
threads in rec.bicycles.tech. I went back to the Great Divide bike shop in Pueblo, Colorado, and
here's what I learned from the cheerful mechanics.

On single-speed freewheel BMX bikes, some riders doing tricks and stunts "grind" better one one side
or the other, so companies like Profile and Primo have found a market in recent years for wrong-side
chains-and-gears that attach on the left.

(Think of left-handed guitars and golf clubs.)

The local bike shop mechanics happily showed me a catalogue listing the Profile SS Cassette HU-1144,
sold in right-hand and left-hand versions.

They pulled out a single-gear rear-cassette, clearly marked "left" and showed me how it freewheels
one way, while its normal mate (with no marking) freewheels the other way.

Even more interesting, they showed me how pedal arms from Primo and Profile are sold as mirror
images, each equally capable of mounting a front chain ring.

If the whole crank assembly were simply reversed to install on the wrong side, the traditional
left-and-right-thread pedals would tend to loosen.

To avoid this, the mounting holes and massive braces appear on both left and right pedal arms,
allowing them to stay on the correct side while just the chain ring moves over to the wrong side.

It's a bit like the godless modern trend in pistols, where safety-catches, slide releases, and
de-cockers can be put on either side for the convenience of left-handed heathens.

See you around the Leftorium,

Ned Flanders

 

[Tom Sherman]

Carl Fogel wrote:
> ... Anyway, here's a site that mentions the odd left-side drive that I saw:
>
> http://www.bmx-test.com/cgi-bin/reviews.cgi?review_id=745
>
> I expect that all my nieces and nephews know this stuff, but we don't seem to get a lot of BMX
> threads in rec.bicycles.tech. I went back to the Great Divide bike shop in Pueblo, Colorado, and
> here's what I learned from the cheerful mechanics.
>
> On single-speed freewheel BMX bikes, some riders doing tricks and stunts "grind" better one one
> side or the other, so companies like Profile and Primo have found a market in recent years for wrong-
> side chains-and-gears that attach on the left....

One could mount these left-hand drive components on the right-hand side of the bike, and then pedal
backwards.

Tom Sherman - Planet Earth

 

[Ted Bennett]

Tom Sherman <[email protected]> wrote:

> Carl Fogel wrote:
> > ... Anyway, here's a site that mentions the odd left-side drive that I saw:
> >
> > http://www.bmx-test.com/cgi-bin/reviews.cgi?review_id=745
> >
> > I expect that all my nieces and nephews know this stuff, but we don't seem to get a lot of BMX
> > threads in rec.bicycles.tech. I went back to the Great Divide bike shop in Pueblo, Colorado, and
> > here's what I learned from the cheerful mechanics.
> >
> > On single-speed freewheel BMX bikes, some riders doing tricks and stunts "grind" better one one
> > side or the other, so companies like Profile and Primo have found a market in recent years for
> > wrong-side chains-and-gears that attach on the left....
>
> One could mount these left-hand drive components on the right-hand side of the bike, and then
> pedal backwards.
>
> Tom Sherman - Planet Earth

You could do that, but it would be a lot simpler to just use a fixed gear. Plus you could still
pedal forwards.

--
Ted Bennett Portland OR

 

[Tom Sherman]

Ted Bennett wrote:
>
> > One could mount these left-hand drive components on the right-hand side of the bike, and then
> > pedal backwards.
> >
> > Tom Sherman - Planet Earth
>
> You could do that, but it would be a lot simpler to just use a fixed gear. Plus you could still
> pedal forwards.

There was a device making the bike show rounds a few years back that turned the chainrings forward
when pedaled either forwards or backwards. The internal friction when pedaling backwards was quite
noticeable and I suspect the device was quite heavy also. An answer to a question almost no one was
asking, I suspect.

Tom Sherman - Planet Earth

 

[Chalo]

Tom Sherman <[email protected]> wrote:

> One could mount these left-hand drive components on the right-hand side of the bike, and then
> pedal backwards.

I have considered the ultimate purpose of these parts, since they made their appearance, to enable
the construction of a symmetrical bike with two drivetrains. (The LHD cassette hubs would be no good
for this; only an RH/LH freewheel hub would do.)

That, in addition to being cool and single-fault-tolerant, would fix the left-crank loosening
problem Jobst Brandt has identified and the asymmetrical frame flex Sheldon Brown has described.

Chalo Colina

 

[Gary Smiley]

Remember the quote by former Red Sox pitcher Bill Lee? "You have two hemispheres in your brain - a
left and a right side. The left side controls the right side of your body and right controls the
left half. It's a fact. Therefore, left-handers are the only people in their right minds."

Carl Fogel wrote:

> Dear Jobst,
>
> In a recent email about a bicycle rear-wheel text that you were asked to edit, you mentioned that
> you dislike abbreviations like DS and NDS for drive-side and non-drive-side.
>
> When you suggested that right and left were shorter, simpler, and just as good as DS and NDS, I
> replied that I'd just seen an odd-looking bike whose chain and gears were on the left.
>
> (I call them gear-side and no-gear-side because my rear wheel is usually upside-down when I'm
> looking at it, so right and left are reversed. God knows what we'd call one of the old-style
> reversible rear wheels with a large climbing cog on one side and a small high-speed cog on
> the other.)
>
> Anyway, here's a site that mentions the odd left-side drive that I saw:
>
> http://www.bmx-test.com/cgi-bin/reviews.cgi?review_id=745
>
> I expect that all my nieces and nephews know this stuff, but we don't seem to get a lot of BMX
> threads in rec.bicycles.tech. I went back to the Great Divide bike shop in Pueblo, Colorado, and
> here's what I learned from the cheerful mechanics.
>
> On single-speed freewheel BMX bikes, some riders doing tricks and stunts "grind" better one one
> side or the other, so companies like Profile and Primo have found a market in recent years for wrong-
> side chains-and-gears that attach on the left.
>
> (Think of left-handed guitars and golf clubs.)
>
> The local bike shop mechanics happily showed me a catalogue listing the Profile SS Cassette HU-
> 1144, sold in right-hand and left-hand versions.
>
> They pulled out a single-gear rear-cassette, clearly marked "left" and showed me how it freewheels
> one way, while its normal mate (with no marking) freewheels the other way.
>
> Even more interesting, they showed me how pedal arms from Primo and Profile are sold as mirror
> images, each equally capable of mounting a front chain ring.
>
> If the whole crank assembly were simply reversed to install on the wrong side, the traditional left-and-right-
> thread pedals would tend to loosen.
>
> To avoid this, the mounting holes and massive braces appear on both left and right pedal arms,
> allowing them to stay on the correct side while just the chain ring moves over to the wrong side.
>
> It's a bit like the godless modern trend in pistols, where safety-catches, slide releases, and de-
> cockers can be put on either side for the convenience of left-handed heathens.
>
> See you around the Leftorium,
>
> Ned Flanders

 

[Jeff Wills]

[email protected] (Chalo) wrote in message news:<[email protected]>...
> Tom Sherman <[email protected]> wrote:
>
> > One could mount these left-hand drive components on the right-hand side of the bike, and then
> > pedal backwards.
>
> I have considered the ultimate purpose of these parts, since they made their appearance, to enable
> the construction of a symmetrical bike with two drivetrains. (The LHD cassette hubs would be no
> good for this; only an RH/LH freewheel hub would do.)
>
> That, in addition to being cool and single-fault-tolerant, would fix the left-crank loosening
> problem Jobst Brandt has identified and the asymmetrical frame flex Sheldon Brown has described.
>
> Chalo Colina

It's been done. I remember seeing it in a BMX magazine ummm... many, many years ago. The difficulty
is getting both freewheels to engage simultaneously. I believe the manufacturer machined up a
special two-sided cassette hub that insured both side's pawls lined up. The manufacturer was asking
$300 to $400 for the rear hub alone, IIRC.

The ads featured the builder's twin daughters, who apparently raced with this system. I have no idea
what their results were...

Jeff

 

[Andymorris]

Carl Fogel wrote:
>
> Anyway, here's a site that mentions the odd left-side drive that I saw:
>
> http://www.bmx-test.com/cgi-bin/reviews.cgi?review_id=745
>

A while ago there was a pursuiter who had double sided drive.

One side was a fixed gear, the other was a freewheel with a larger sprocket. He started with the
fixed gear only just engaged with its thread.

By doing this the rider enjoyed a lower gear, using the freewheel, for the first few pedal strokes
until the fixed gear hit the end of its thread that would become the driving gear and the freewheel
would start freewheeling.

--
Andy Morris

AndyAtJinkasDotFreeserve.Co.UK

Love this:
Put an end to Outlook Express's messy quotes
http://home.in.tum.de/~jain/software/oe-quotefix/

 

[Jobst Brandt]

Andy Morris writes:

>> Anyway, here's a site that mentions the odd left-side drive that I saw:

>> http://www.bmx-test.com/cgi-bin/reviews.cgi?review_id=745

> A while ago there was a pursuiter who had double sided drive.

> One side was a fixed gear, the other was a freewheel with a larger sprocket. He started with the
> fixed gear only just engaged with its thread.

> By doing this the rider enjoyed a lower gear, using the freewheel, for the first few pedal strokes
> until the fixed gear hit the end of its thread that would become the driving gear and the
> freewheel would start freewheeling.

That may be, but all sorts of two speed devices have been tried and found useless. Even the best
funded record attempts have not used them. The best gear in which to start is the one in which you
plan to ride. This is true not only on the track but also on the road, assuming the rider does not
have a physical hindrance.

Humans are not Peterbilt trucks that do better going through many gears to get up to speed. Gears on
road bicycles are for climbing long hills, not for starting from a stop sign. Nevertheless, there
are riders who shift down for stops on the flat and run through the gears. I believe, had they
ridden with other bikies on a casually competitive basis they would have ;earned that they are at a
disadvantage in their method.

> http://home.in.tum.de/~jain/software/oe-quotefix/

Done that!

Jobst Brandt [email protected]

 

[Ryan Cousineau]

In article <[email protected]>,
[email protected] wrote:

> Andy Morris writes:
>
> >> Anyway, here's a site that mentions the odd left-side drive that I saw:
>
> >> http://www.bmx-test.com/cgi-bin/reviews.cgi?review_id=745
>
> > A while ago there was a pursuiter who had double sided drive.
>
> > One side was a fixed gear, the other was a freewheel with a larger sprocket. He started with the
> > fixed gear only just engaged with its thread.
>
> > By doing this the rider enjoyed a lower gear, using the freewheel, for the first few pedal
> > strokes until the fixed gear hit the end of its thread that would become the driving gear and
> > the freewheel would start freewheeling.
>
> That may be, but all sorts of two speed devices have been tried and found useless. Even the best
> funded record attempts have not used them. The best gear in which to start is the one in which you
> plan to ride. This is true not only on the track but also on the road, assuming the rider does not
> have a physical hindrance.
>
> Humans are not Peterbilt trucks that do better going through many gears to get up to speed. Gears
> on road bicycles are for climbing long hills, not for starting from a stop sign. Nevertheless,
> there are riders who shift down for stops on the flat and run through the gears. I believe, had
> they ridden with other bikies on a casually competitive basis they would have ;earned that they
> are at a disadvantage in their method.

Really? Few competitive road cycling events (this excludes track oddities like the kilo, which are
mandated as fixed-gear, singlespeed anyways) put any significant emphasis on the start. Virtually
all road races, from the lowliest crit on upwards, have essentially neutral starts. Only in short
TTs (think prologue length) is the start enough of a factor to really bother with.

But I commute to work, where for various reasons the stoplight grands prix are regular features of
my ride. I'm pretty sure after repeated trials that I can usually accelerate from a stop to cruising
speed faster by starting 2-4 gears below my cruising ratio, and that's on my slow-shifting DT-
equipped bike. On the brifteur race bike, I happily drag-race cars, something not easily
accomplished starting from the big gear.

In general, it feels like that first spin or two up to speed takes forever in a big gear.

I'll have to watch carefully in my next MTB race. There, because of the usual short sprint to enter
the singletrack trails, a fast start is a definite advantage. I can tell you two things: I usually
outsprint better dirt-riders, and I usually shift a few times getting up to speed. I will evaluate
my technique and that of fellow racers next race.

--
Ryan Cousineau, [email protected] http://www.sfu.ca/~rcousine President, Fabrizio Mazzoleni Fan Club

 

[Carl Fogel]

[email protected] wrote in message news:<[email protected]>...
> Andy Morris writes:
>
> >> Anyway, here's a site that mentions the odd left-side drive that I saw:
>
> >> http://www.bmx-test.com/cgi-bin/reviews.cgi?review_id=745
>
> > A while ago there was a pursuiter who had double sided drive.
>
> > One side was a fixed gear, the other was a freewheel with a larger sprocket. He started with the
> > fixed gear only just engaged with its thread.
>
> > By doing this the rider enjoyed a lower gear, using the freewheel, for the first few pedal
> > strokes until the fixed gear hit the end of its thread that would become the driving gear and
> > the freewheel would start freewheeling.
>
> That may be, but all sorts of two speed devices have been tried and found useless. Even the best
> funded record attempts have not used them. The best gear in which to start is the one in which you
> plan to ride. This is true not only on the track but also on the road, assuming the rider does not
> have a physical hindrance.
>
> Humans are not Peterbilt trucks that do better going through many gears to get up to speed. Gears
> on road bicycles are for climbing long hills, not for starting from a stop sign. Nevertheless,
> there are riders who shift down for stops on the flat and run through the gears. I believe, had
> they ridden with other bikies on a casually competitive basis they would have ;earned that they
> are at a disadvantage in their method.
>
> > http://home.in.tum.de/~jain/software/oe-quotefix/
>
> Done that!
>
> Jobst Brandt [email protected]

Dear Jobst,

Am I correct in hoping that your suggestion that "The best gear in which to start is the one in
which you plan to ride" was not meant to apply to carbon-based life-forms that diesel happily along
in 53 x 11, both up and down the Arkansas River, at 20-25 mph and 50-60 rpm?

Weird as I am, it's going to take a remarkably convincing argument for me to stop shifting down at
that stupid traffic light and try to start out from a dead stop in high gear.

Come to think of it, don't human strides start off at walking length and then increase as they start
trotting and then widen even further as they begin to run?

Carl Fogel

 

[David L. Johnso]

On Wed, 17 Dec 2003 22:39:54 +0000, Carl Fogel wrote:

> Am I correct in hoping that your suggestion that "The best gear in which to start is the one in
> which you plan to ride" was not meant to apply to carbon-based life-forms that diesel happily
> along in 53 x 11, both up and down the Arkansas River, at 20-25 mph and 50-60 rpm?

Why on earth would you ride along on the flats in such a gear, anyway?

> Weird as I am, it's going to take a remarkably convincing argument for me to stop shifting down at
> that stupid traffic light and try to start out from a dead stop in high gear.

How 'bout an argument to not cruise in such a gear to begin with?

--

David L. Johnson

__o | There is always an easy solution to every human problem - neat, _`\(,_ | plausible, and
wrong. --H.L. Mencken (_)/ (_) |

 

[Ron Hardin]

> > A while ago there was a pursuiter who had double sided drive.
>
> > One side was a fixed gear, the other was a freewheel with a larger sprocket. He started with the
> > fixed gear only just engaged with its thread.
>
> > By doing this the rider enjoyed a lower gear, using the freewheel, for the first few pedal
> > strokes until the fixed gear hit the end of its thread that would become the driving gear and
> > the freewheel would start freewheeling.

It doesn't lower the gear if the fixed gear slips, it just reduces the force applied to the wheel.
If he were starting up a hill, the bike would go backwards when he was pedalling forwards, which no
gearing does.
--
Ron Hardin [email protected]

On the internet, nobody knows you're a jerk.

 

[Dianne_1234]

On Thu, 18 Dec 2003 00:51:14 -0000, "AndyMorris"
<[email protected]> wrote:

>Carl Fogel wrote:
>>
>> Anyway, here's a site that mentions the odd left-side drive that I saw:
>>
>> http://www.bmx-test.com/cgi-bin/reviews.cgi?review_id=745
>>
>
>A while ago there was a pursuiter who had double sided drive.
>
>One side was a fixed gear, the other was a freewheel with a larger sprocket. He started with the
>fixed gear only just engaged with its thread.
>
>By doing this the rider enjoyed a lower gear, using the freewheel, for the first few pedal strokes
>until the fixed gear hit the end of its thread that would become the driving gear and the freewheel
>would start freewheeling.

Former kilo world record holder Shaun Wallace. It really worked! Brilliant!

Only one small detail: both chains were on the same side of the bike. That way the fixed gear would
advance on its threads. Also conveniently hid the second chain unless you looked really closely!

The Canadian pursuiter (Lovell?) was the guy with the two-speed bike that had one chain on each
side. Not sure how that worked.

About 1981 Pinarello showed a Kilo bike with a chain on each side. IIRC, it wasn't for two speeds,
but for frame stiffness. I might have misunderstood it, but at the time my impression was that after
the first 2.5 crank revolutions or so, the left side master link passed a trigger pin on the
downtube that disconnected it. After about another 2 turns turns of the crank the chain eventually
fell off onto the track, to be left behind. The right side chain remained to finish the race.

Also, don't Aussie track riders run the chain on the left side always?

 

[Ron Hardin]

Ron Hardin wrote:
>
> > > A while ago there was a pursuiter who had double sided drive.
> >
> > > One side was a fixed gear, the other was a freewheel with a larger sprocket. He started with
> > > the fixed gear only just engaged with its thread.
> >
> > > By doing this the rider enjoyed a lower gear, using the freewheel, for the first few pedal
> > > strokes until the fixed gear hit the end of its thread that would become the driving gear and
> > > the freewheel would start freewheeling.
>
> It doesn't lower the gear if the fixed gear slips, it just reduces the force applied to the wheel.
> If he were starting up a hill, the bike would go backwards when he was pedalling forwards, which
> no gearing does.

Oh I see, the freewheel is preventing that.
--
Ron Hardin [email protected]

On the internet, nobody knows you're a jerk.

 

[Sheldon Brown]

I rode my new left-side drive Gunnar Street dog in to work this morning, it's fun but it's hard to
make myself pick it up from the right side to carry it over the stairs.

I bought some Sugino AT tandem cranks on the Internet, with this in mind. I'm running my usual 42/15
fixed gear.

I still haven't gotten used to how the bike looks, and it feels weird to tuck my _left_ trouser leg
into my sock, instead of my right one!

Quoth Jobst Brandt:

> ...The best gear in which to start is the one in which you plan to ride. This is true not only on
> the track but also on the road, assuming the rider does not have a physical hindrance.

I'm a bit schizophrenic about this. I mostly ride fixed-gear, where this is a non-issue, but, when I
_do_ ride on multispeed bikes, I'm a constant shifter, and tend to maintain my cadence within a very
narrow range.

> Humans are not Peterbilt trucks that do better going through many gears to get up to speed. Gears
> on road bicycles are for climbing long hills, not for starting from a stop sign. Nevertheless,
> there are riders who shift down for stops on the flat and run through the gears. I believe, had
> they ridden with other bikies on a casually competitive basis they would have ;earned that they
> are at a disadvantage in their method.

This may well be true for old-fashioned frame-mounted shifters, but not so for those of us who have
our shift controls on the handlebars.

Reaching down to the down tube does have a cost of perhaps half a stroke's worth of power, but this
is not the case with handlebar-mounted shifters.

I know how fond you are of the "Peterbuilt" schtick, but this is a case of "reasoning by ridicule."
You have never, so far as I know, presented any evidence to suggest that shifting this way is not
beneficial to the cyclist who is interested in conserving energy and strain.

I do know that, in my own experience, when I run through a bunch of gears as I leave a stop light, I
leave most cyclists (and many cars) in the dust for the first half block, even cylcists who are
otherwise much stronger and faster than a 59 year old fat guy like myself.

I do this partly because it's fun, and partly because I feel it is safer to clear the intersection
as promptly as possible, to avoid the crush of traffic.

Sheldon "Never Liked Downtube Shifters" Brown +----------------------------------------------------------------------
+
| I am come-in a very moralizing strain, to observe that our | pleasures in this world are always to
| be paid for, and that we | often purchase them at a great disadvantage, giving ready-monied |
| actual happiness for a draft on the future, that may not be honored. | -- Henry Tilney, Northanger
| Abbey by Jane Austen |
+----------------------------------------------------------------------+ Harris Cyclery, West
Newton, Massachusetts Phone 617-244-9772 FAX 617-244-1041 http://harriscyclery.com Hard-to-find
parts shipped Worldwide http://captainbike.com http://sheldonbrown.com

 

[Dietrich Wiegma]

Ryan Cousineau <[email protected]> wrote in message news:<[email protected]>...
> In article <[email protected]>, [email protected] wrote:
>
> > Andy Morris writes:
> >
> > > By doing this the rider enjoyed a lower gear, using the freewheel, for the first few pedal
> > > strokes until the fixed gear hit the end of its thread that would become the driving gear and
> > > the freewheel would start freewheeling.
> >
> > That may be, but all sorts of two speed devices have been tried and found useless. Even the best
> > funded record attempts have not used them. The best gear in which to start is the one in which
> > you plan to ride. This is true not only on the track but also on the road, assuming the rider
> > does not have a physical hindrance.
>
> Really? Few competitive road cycling events (this excludes track oddities like the kilo, which are
> mandated as fixed-gear, singlespeed anyways) put any significant emphasis on the start. Virtually
> all road races, from the lowliest crit on upwards, have essentially neutral starts. Only in short
> TTs (think prologue length) is the start enough of a factor to really bother with.
>
The key to BMX racing is the sprint from the start to the first corner. 2 speed systems for BMX were
tried and abandoned in the early 1980s.

Dietrich Wiegmann

 

[Carl Fogel]

"David L. Johnson" <[email protected]> wrote in message news:<[email protected]>...
> On Wed, 17 Dec 2003 22:39:54 +0000, Carl Fogel wrote:
>
> > Am I correct in hoping that your suggestion that "The best gear in which to start is the one in
> > which you plan to ride" was not meant to apply to carbon-based life-forms that diesel happily
> > along in 53 x 11, both up and down the Arkansas River, at 20-25 mph and 50-60 rpm?
>
> Why on earth would you ride along on the flats in such a gear, anyway?
>
> > Weird as I am, it's going to take a remarkably convincing argument for me to stop shifting down
> > at that stupid traffic light and try to start out from a dead stop in high gear.
>
> How 'bout an argument to not cruise in such a gear to begin with?

Dear David,

So why not?

Carl Fogel

 

[Jobst Brandt]

Carl Fogel writes:

> Am I correct in hoping that your suggestion that "The best gear in which to start is the one in
> which you plan to ride" was not meant to apply to carbon-based life-forms that diesel happily
> along in 53 x 11, both up and down the Arkansas River, at 20-25 mph and 50-60 rpm?

Your choice of gear tells me that you ride at less than the speeds you suggest. 50-60 rpm would give
18.8-22.6 mph with an average size wheel. I think you ought to get into TT racing if you can pull
that off in such a gear. I haven't seen anyone riding that fast on the flats in anywhere near that
gear, but there may be exceptional riders that I have overlooked.

> Weird as I am, it's going to take a remarkably convincing argument for me to stop shifting down at
> that stupid traffic light and try to start out from a dead stop in high gear.

Yes and it will take even more to convince riders that turning their bicycle upside down to take the
rear wheel out and repair a flat is not useful.

> Come to think of it, don't human strides start off at walking length and then increase as they
> start trotting and then widen even further as they begin to run?

There go those question marks... again.

Jobst Brandt [email protected]

 

[Jobst Brandt]

Sheldon Brown writes:

> This may well be true for old-fashioned frame-mounted shifters, but not so for those of us who
> have our shift controls on the handlebars.

> Reaching down to the down tube does have a cost of perhaps half a stroke's worth of power, but
> this is not the case with handlebar-mounted shifters.

This makes it sound like there are a lot of gears top be shifted but in reality I can't imagine more
than two or three and not accelerating at any notable rate, time between shifts is large. A parallel
oddity can be found in drag racing where speeds go from 0-300+mph in 4.4 sec.

http://www.nhra.com/stats/natrecord.html

in the same gear.

> I know how fond you are of the "Peterbuilt" schtick, but this is a case of "reasoning by
> ridicule." You have never, so far as I know, presented any evidence to suggest that shifting this
> way is not beneficial to the cyclist who is interested in conserving energy and strain.

Ahh. There's the catch, "energy and strain". As we get older, we tend to avoid these. When was the
last time you won a city limits sprint? Those take energy and strain as do climbing over big hills
like Sonora Pass CA with its 20% grades at the summit... but can you spell Peterbilt?

> I do know that, in my own experience, when I run through a bunch of gears as I leave a stop light,
> I leave most cyclists (and many cars) in the dust for the first half block, even cylcists who are
> otherwise much stronger and faster than a 59 year old fat guy like myself.

I guess traffic has changed. Around here, one of the best trackie training tricks is to beat cars
across the intersection when the light turns green. It ain't easy and the cars aren't even
competing. Of course they have automatic transmissions, so that ain't fair.

> I do this partly because it's fun, and partly because I feel it is safer to clear the intersection
> as promptly as possible, to avoid the crush of traffic.

> Sheldon "Never Liked Downtube Shifters" Brown

I cheat and cross before the light changes if I can.

Jobst Brandt [email protected]