Update on my gearing issue



P

Preston Crawford

Guest
So I talked to the shop today. They were on top of things. As a few of you
on rec.bicycles.misc or rec.bicycles.tech (I didn't cross-post, but posted
in both forums) predicted. They suggested I widen the rear cassette. So I
think they're putting a mountain bike derailleur and something like a
36/11 on the back. Then they're going to put a 39 on the front. I think
that should do the trick. Right now I'm running (confirmed this morning
now that I have a bit of an education in gearing, etc.) a 30 on the front
of my road bike with a 28 on the back. What do you guys think?

Preston
 
I think if you need a smaller gear than a 30 X 28 on a road bike, then
you should take up a new sport. A 36 in back ?!? Man, you'll have to
spin like crazy just to stay upright.
 
On 2004-12-27, Ed Sullivan <[email protected]> wrote:
> I think if you need a smaller gear than a 30 X 28 on a road bike, then
> you should take up a new sport. A 36 in back ?!? Man, you'll have to
> spin like crazy just to stay upright.
>


Everyone is built differently. I'm not trying to win races. Just trying to
get to work and get exercise.

Preston
 
Preston Crawford wrote:
> So I talked to the shop today. They were on top of things. As a few

of you
> on rec.bicycles.misc or rec.bicycles.tech (I didn't cross-post, but

posted
> in both forums) predicted. They suggested I widen the rear cassette.

So I
> think they're putting a mountain bike derailleur and something like a
> 36/11 on the back. Then they're going to put a 39 on the front. I

think
> that should do the trick. Right now I'm running (confirmed this

morning
> now that I have a bit of an education in gearing, etc.) a 30 on the

front
> of my road bike with a 28 on the back. What do you guys think?
>
> Preston


You're probably getting a 11-34 cassette on the rear. 36-tooth rear
cogs are nonexistent, as far as I know. That should be adequate for
most routes.

As to your finished configuration, is your small chainring going to be
30 teeth or 39 teeth? Your post has me confused.

FWIW: I have a 12-28 8-speed cassette with a 26-39-53 triple chainring.
For commuting purposes, I find that the middle (39-tooth) chainring
adequate- I rarely use the big chainring and almost never use the
small. My commute includes a short 10-percent climb, but I manage it in
the 39/24 gear... and that's on a loaded Tour Easy recumbent carrying
my 220-pound, post-holiday-party fat butt.

Jeff
 
On 2004-12-27, [email protected] <[email protected]> wrote:
> You're probably getting a 11-34 cassette on the rear. 36-tooth rear
> cogs are nonexistent, as far as I know. That should be adequate for
> most routes.


Weird. They said 36. Either way I should be fine.

> As to your finished configuration, is your small chainring going to be
> 30 teeth or 39 teeth? Your post has me confused.


39. My road bike, my Trek 1000 has a triple and the smallest chainring is
a 30. I generally (for whatever reason) find myself usually in the first
or second chainring anyway. Never in the 3rd and actually mostly in the
first. I do lots of spinning. So the combo they're putting together seems
about right.

> FWIW: I have a 12-28 8-speed cassette with a 26-39-53 triple chainring.
> For commuting purposes, I find that the middle (39-tooth) chainring
> adequate- I rarely use the big chainring and almost never use the
> small. My commute includes a short 10-percent climb, but I manage it in
> the 39/24 gear... and that's on a loaded Tour Easy recumbent carrying
> my 220-pound, post-holiday-party fat butt.


Yeah, everyone is different, of course. I'm pulling more weight and I have
strong legs, but not necessarily good hill climbing legs. It's hard to
explain. I can climb at a good clip, forever. When my wife (who has
completed a half-Ironman and a century, so she's definitely tougher than
me) and I did this mountainous ride this summer, on every hill I would
have to drop her. I can just ride a nice clip, a nice fast cadence up the
hill for miles and miles and miles. I just have to do it in a low gear. On
the other hand, when I'm on flat ground I rarely get out of the 1st
chainring of the triple, much less the 3rd. So I don't know what that
means in terms of how I'm built, but I need those gears, believe me.

Preston
 
On Mon, 27 Dec 2004 14:20:20 -0600, Preston Crawford
<[email protected]> wrote:

>On 2004-12-27, Ed Sullivan <[email protected]> wrote:
>> I think if you need a smaller gear than a 30 X 28 on a road bike, then
>> you should take up a new sport. A 36 in back ?!? Man, you'll have to
>> spin like crazy just to stay upright.
>>

>
>Everyone is built differently. I'm not trying to win races. Just trying to
>get to work and get exercise.
>
>Preston


Dear Preston,

A brisk walk pushing a bicycle on level ground is about 4
mph.

For a 700c road tire, here are some low-speed rpm figures
for the gearing that you've mentioned.

front/rear rpm speed

39/36 takes 45~~63 rpm for 5-7 mph
30/28 takes 59~~83 rpm for 5-7 mph
30/36 takes 76~106 rpm for 5-7 mph

30/36 takes 45~61 rpm for 3-4 mph

Most people climb at a lower rpm than they pedal on flat
ground--and most people who are commuting don't spin 80-100
rpm anyway, being more comfortable around 50-70 rpm.

That's what Ed has in mind when he points out that you'll
have to spin like crazy just to stay upright with a 30 front
x 36 rear.

With such low gearing, 45 to 61 rpm produces only 3 to 4
mph. It's usually easier to get off and walk than to balance
while thrashing your legs at such low speeds.

You'll probably be more comfortable riding up hills using
your larger rear cogs and then simply walking when it gets
too steep, instead of shifting down into a gear as low as a
30 front x 36 rear.

Luckily, you won't need elaborate calculations--a few
moments on the hill will tell you whether you'd rather spin
that fast while going so slowly, or get off and walk. Having
an extra-low gear won't hurt anything.

Carl Fogel
 
On Mon, 27 Dec 2004 14:49:11 -0600, Preston Crawford
<[email protected]> wrote:

I used an 11-34 rear cassette and a 29T single chainring on the road
bike to climb Ascutney Mtn... and I used the 34T... and reduced the
"time to climb" by over 5 minutes compared to "standard" gearing.

Nothing wrong with ultra low gears.

charlieb in ct
 
On 2004-12-28, Charles Beristain <[email protected]> wrote:
> On Mon, 27 Dec 2004 14:49:11 -0600, Preston Crawford
><[email protected]> wrote:
>
> I used an 11-34 rear cassette and a 29T single chainring on the road
> bike to climb Ascutney Mtn... and I used the 34T... and reduced the
> "time to climb" by over 5 minutes compared to "standard" gearing.
>
> Nothing wrong with ultra low gears.
>
> charlieb in ct


Thank you.

Preston
 
Preston Crawford said:
On 2004-12-28, Charles Beristain <[email protected]> wrote:
> On Mon, 27 Dec 2004 14:49:11 -0600, Preston Crawford
><[email protected]> wrote:
>
> I used an 11-34 rear cassette and a 29T single chainring on the road
> bike to climb Ascutney Mtn... and I used the 34T... and reduced the
> "time to climb" by over 5 minutes compared to "standard" gearing.
>
> Nothing wrong with ultra low gears.
>
> charlieb in ct


Thank you.

Preston

We have 24 tooth front and tooth 34 rear on our tandem and I have the same on my touring bicycles. While we don't use it often, when we do it is nice to spin along and not need to climb off on a steep hill/mountain, walk for a ways until we can ride again, and then remount. We pass unmounted walking riders often when in "granny + 34 tooth" rear.
 
On Tue, 28 Dec 2004 15:15:03 +1100, daveornee
<[email protected]> wrote:

>
>Preston Crawford Wrote:
>> On 2004-12-28, Charles Beristain <[email protected]> wrote:
>> > On Mon, 27 Dec 2004 14:49:11 -0600, Preston Crawford
>> ><[email protected]> wrote:
>> >
>> > I used an 11-34 rear cassette and a 29T single chainring on the

>> road
>> > bike to climb Ascutney Mtn... and I used the 34T... and reduced the
>> > "time to climb" by over 5 minutes compared to "standard" gearing.
>> >
>> > Nothing wrong with ultra low gears.
>> >
>> > charlieb in ct

>>
>> Thank you.
>>
>> Preston

>
>We have 24 tooth front and tooth 34 rear on our tandem and I have the
>same on my touring bicycles. While we don't use it often, when we do
>it is nice to spin along and not need to climb off on a steep
>hill/mountain, walk for a ways until we can ride again, and then
>remount. We pass unmounted walking riders often when in "granny + 34
>tooth" rear.


Dear Dave,

With 24 front x 34 rear, a 700c wheel needs 55-90 rpm to
roll 3-5 mph, so I expect that you're an interesting sight
as you spin uphill.

Do you use a synchronous pedal arrangement, if that's the
term for each rider pushing down on the left pedal at the
same time, or an alternating setup?

Carl Fogel
 
[email protected] wrote:

> ...
> Most people climb at a lower rpm than they pedal on flat
> ground--and most people who are commuting don't spin 80-100
> rpm anyway, being more comfortable around 50-70 rpm....


I must not be most people, since I prefer to climb at 110-120 rpm
cadence. I can do this on most grades with a 22/34 low gear and a
virtual 30-inch diameter (~77 cm) drivewheel.

--
Tom Sherman - Near Rock Island
 
Ed-<< I think if you need a smaller gear than a 30 X 28 on a road bike, then
you should take up a new sport. >><BR><BR>

Do you tell all guys that are tall they oughta play basketball?

Proper gearing is what works for this guy and keeps him on the bike, even if it
isn't what you would use.

Peter Chisholm
Vecchio's Bicicletteria
1833 Pearl St.
Boulder, CO, 80302
(303)440-3535
http://www.vecchios.com
"Ruote convenzionali costruite eccezionalmente bene"
 
On Tue, 28 Dec 2004 <SNIP>

Dear Dave,

With 24 front x 34 rear, a 700c wheel needs 55-90 rpm to
roll 3-5 mph, so I expect that you're an interesting sight
as you spin uphill.

Do you use a synchronous pedal arrangement, if that's the
term for each rider pushing down on the left pedal at the
same time, or an alternating setup?

Carl Fogel

Our cadence is usually in the 85 - 95 RPM area (as long as the captain keeps up with the "Rear Admiral"}, with the exception of some very steep downhills where we top out around 125 RPM.
We have tried various pedal position arrangements, but usually revert to right pedal down at the same time for both of us.
It is quite a sight and sound experience for us to climb steep grades. We have never fallen over yet or had to dismount to walk.
 
Tom Sherman wrote:

> I must not be most people, since I prefer to climb at 110-120 rpm
> cadence.


I'll say. I've never seen anyone climb at that high a cadence, and I
spend a lot of time on hills. And I do mean a *lot* of time.
--
terry morse Palo Alto, CA http://bike.terrymorse.com/
 
Terry Morse wrote:

> Tom Sherman wrote:
>
>
>>I must not be most people, since I prefer to climb at 110-120 rpm
>>cadence.

>
>
> I'll say. I've never seen anyone climb at that high a cadence, and I
> spend a lot of time on hills. And I do mean a *lot* of time.


I must be the physiological opposite of Jobst Brandt and Jan Ulrich.

> --
> terry morse Palo Alto, CA http://bike.terrymorse.com/


I believe the space after the "--" in your signature separator is missing.

--
Tom Sherman - Near Rock Island