Efficient use of gears

hi, how should i use the gears ,for the most efficient power output,
Which to use , when 2 near overlap,
any rule of thumb,any scientific way,
t.i.a.

Antonio wrote:
hi, how should i use the gears ,for the most efficient power output,
Which to use , when 2 near overlap,
any rule of thumb,any scientific way,
t.i.a.


Conventional wisdom says to use a gear that allows you to sping your
cranks at around 90 RPM.

Typical power outputs for a normal adult rider are around .1 HP.
Changing your gears won't change your power, but will allow you to make
the most effective and efficient use of what power you have.

Read "Bicycling Science" for more on this.

Antonio wrote:
hi, how should i use the gears ,for the most efficient power output,
Which to use , when 2 near overlap,
any rule of thumb,any scientific way,
t.i.a.

Well, if you want to get technical, and hey why not, this is
rec.bike.tech. It's good to know your exact shift pattern. Check out
this site. After you enter the info the first time you can recalculate
for cadence/MPH at the bottom of the page. The logical sequence of
gears is not what you might think especially if you have a triple
chainring. This is really usefull when your on the flats and your
looking for just that right gear.
Click Here http://www.panix.com/~jbarrm/cycal/cycal.30f.html

"John" wrote in message
ups.com...

Well, if you want to get technical, and hey why not, this is
rec.bike.tech.

It is not. Thank goodness.

--
Warm Regards,

Claire Petersky
Personal page: http://www.geocities.com/cpetersky/
See the books I've set free at:
http://bookcrossing.com/referral/Cpetersky

If you want to know which combinations are "redundant", find out how
many teeth are on each cog (rear gears) and each chain wheel (front
gears) and use this "scientific formula" to determine the ratios:
Chainwheel teeth divided by cog teeth then multiply by wheel diameter.

Do this for each combination. This will tell you which ones are
repeated.

As for how to use them, simply find a comfortable cadence (pedal RPM).
most efficient is obtained above 75-80 RPM, the faster the better, but
above 90 can be hard to maintain on long or steep hills unless you're
strong.

Now that you know where each gear stands in relationship to the others,
simply chose the one that let's you maintain that RPM for the gradient
you're facing.

For a more detailed explination of using gears effeciently:

http://www.geocities.com/czcorner/tech4.html

For explaining how their arranged:

http://www.geocities.com/czcorner/tech5.html

- -

"May you have the winds at your back,
And a really low gear for the hills!"

Chris Zacho ~ "Your Friendly Neighborhood Wheelman"

Chris'Z Corner
http://www.geocities.com/czcorner

In article
,
(Chris Zacho "The Wheelman")
wrote:

As for how to use them, simply find a comfortable cadence (pedal RPM).
most efficient is obtained above 75-80 RPM, the faster the better, but
above 90 can be hard to maintain on long or steep hills unless you're
strong.

This is so simplistic as to be just plain wrong.

The amount of power expended to the amount of power
delivered to the bicycle's drive train is one defintion of
efficiency. Here the optimal cadence is 40-50.

The bicyclist finds himself in varying conditions and with
various goals and physical capacities. As the bicyclist
chooses to deliver more and more power to the bicycle the
optimal cadence increases, but the efficiency decreases as
defined in the previous paragraph. The best cadence is a
function of the fraction of the maximum power you can
produce and increases with the fraction of your maximum
power that you expend. Actual efficiency decreases as
cadence increases.

You should not take my word for it. Ask in
rec.bicycles.tech or rec.bicycles.racing.

--
Michael Press

Nice site - thanks.

I'm curious, how many of you actually shift gears in order? For me, to
go up one gear, I'd have to go to the big ring and then go to two
larger cogs. To go to the next higher gear, I'd have to go to the
small ring and go to 3 smaller cogs.



On 20 Sep 2005 23:06:52 -0700, "John" wrote:


Antonio wrote:
hi, how should i use the gears ,for the most efficient power output,
Which to use , when 2 near overlap,
any rule of thumb,any scientific way,
t.i.a.

Well, if you want to get technical, and hey why not, this is
rec.bike.tech. It's good to know your exact shift pattern. Check out
this site. After you enter the info the first time you can recalculate
for cadence/MPH at the bottom of the page. The logical sequence of
gears is not what you might think especially if you have a triple
chainring. This is really usefull when your on the flats and your
looking for just that right gear.
Click Here http://www.panix.com/~jbarrm/cycal/cycal.30f.html

wrote:

I'm curious, how many of you actually shift gears in order? For me, to
go up one gear, I'd have to go to the big ring and then go to two
larger cogs. To go to the next higher gear, I'd have to go to the
small ring and go to 3 smaller cogs.

I do not. I ride primarily in the middle sprocket (of three). I shift
only to the small one if climbing steep hills, and only to the upper one
if I'm going too fast for the middle one.

On our tandem I shift on average about once a minute. We always seem to
be going either up or down, and when pulling a kiddo in a trailer it
makes a huge difference even on gentle grades. If I let the cadence
fall too far out of the 80 to 95 range my stoker lets me know....

Rich

On Thu, 06 Oct 2005 06:55:15 -0600, Rich wrote:

wrote:

I'm curious, how many of you actually shift gears in order? For me, to
go up one gear, I'd have to go to the big ring and then go to two
larger cogs. To go to the next higher gear, I'd have to go to the
small ring and go to 3 smaller cogs.

I do not. I ride primarily in the middle sprocket (of three). I shift
only to the small one if climbing steep hills, and only to the upper one
if I'm going too fast for the middle one.

I train in the large sprocket, and get most hills in the 52x19, though my
cadence suffers. I'm trying to keep it at least 70 on the short hills
around here.

For longer rides that are near my limit, I'll go to the middle ring, same
gears in back. That nearly instantly gives me faster more favorable
cadence, though I try to maintain at least 80rpm when training, which
requires a lot of concentration, for me. I figure - make it harder in
training and then ease off when going for a longer ride, or a group ride or
event.

jj

wrote in message
...

Nice site - thanks.

I'm curious, how many of you actually shift gears in order? For me, to
go up one gear, I'd have to go to the big ring and then go to two
larger cogs. To go to the next higher gear, I'd have to go to the
small ring and go to 3 smaller cogs.




I used ot shift like that, back in the 10-speed days. Today, with so many
more closely-spaced gears, I don't think there's much benefit in following
the exact order of gears by constantly shifting the front ring. I think of
the front rings more in terms of a gear range now.