changing ratios

VisionSet said:

I have a 52/39 12/23 9 speed setup on my road bike.

I think I need to change the 39 ring for a smaller one.

You'll only be able to fit a 38 to a 130mm PCD Shimano
double chainset so it will not make a great deal of
difference. You could fit a triple or a compact double with
110mm PCD. Large rear sprockets will of course make a small
difference too, Shimano road cassettes go up to 27.

You have many options, the cost will probably dictate
your choice.

"MSeries" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

VisionSet said:

I have a 52/39 12/23 9 speed setup on my road bike.

I think I need to change the 39 ring for a smaller one.

You'll only be able to fit a 38 to a 130mm PCD Shimano
double chainset so

it

Quoted message said:

will not make a great deal of difference. You could fit a
triple or a compact double with 110mm PCD. Large rear
sprockets will of course make a small difference too,
Shimano road cassettes go up to 27.

You have many options, the cost will probably dictate
your choice.

Doh, hadn't thought about the pcd limitation. I think I'll
go for a new cassette and a new chain and swap between them
depending on the terrain (obviously not en route!!)

mmmm 12/25 or 12/27 both give me much lower than I've had
before I'm tempted to go 12/25 as I know I'll miss the close
ratio, but will it be low enough? Don't you just know it'll
be wrong whichever I go for!

--
Mike W

VisionSet said:

mmmm 12/25 or 12/27 both give me much lower than I've had
before I'm tempted to go 12/25 as I know I'll miss the
close ratio, but will it be low enough?

What a shame ShimaNO don't offer a 13/27. That'd be good,
wouldn't it? I think you could make one up, though, one way
or the other: Sprockets from more than one Shimano cassette
and/or with one/some Marchisio* sprockets.

* anysystem.deanysystem.deOpen ↗
* www.parker-international.co.uk/components.htm

Quoted message said:

Don't you just know it'll be wrong whichever I go for!

It won't be wrong, it just might not be right enough :-)

~PB

VisionSet said:

mmmm 12/25 or 12/27 both give me much lower than I've had
before I'm tempted to go 12/25 as I know I'll miss the
close ratio, but will it be low enough? Don't you just
know it'll be wrong whichever I go for!

39x25 will get you up most things, including the short 1 in
6 out of my village, and the ratios on the 12-25 cassette
are still close. If you live in the North Pennines you may
want something lower.

Zog The Undeniable said:

VisionSet said:

mmmm 12/25 or 12/27 both give me much lower than I've had
before I'm tempted to go 12/25 as I know I'll miss the
close ratio, but will it be low enough? Don't you just
know it'll be wrong whichever I go for!

39x25 will get you up most things, including the short 1
in 6 out of my village, and the ratios on the 12-25
cassette are still close. If you live in the North
Pennines you may want something lower.

[censored], why is it I can't do steep hills on a 30x25
then? a 39x25 is a vaguely low-middling gear for me, not
a very lowest one. I can only imagine you get up those
hills by standing on the pedals and doing the high power
low rpm thing!

--

Velvet

Velvet <[email hidden]> wrote:

: [censored], why is it I can't do steep hills on a 30x25
: then? a 39x25 is a vaguely low-middling gear for me, not
: a very lowest one. I can only imagine you get up those
: hills by standing on the pedals and doing the high power
: low rpm thing!

Climbing speed = power to weight ratio. Even a small amount
of extra weight makes a large difference to how much power
you have to put out on a steep climb.

Climbing style does come into it though - there comes a
point where standing on the pedals is the only way to get
up hills so it's worth practising, but many riders find
they climb better this way anyway (at least for short
sharp climbs)

--
Arthur Clune clune.orgclune.orgOpen ↗ "Technolibertarians make a
philosophy out of a personality defect"
- Paulina Borsook

"Velvet" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

[censored], why is it I can't do steep hills on a 30x25
then? a 39x25 is a vaguely low-middling gear for me, not
a very lowest one. I can only imagine you get up those
hills by standing on the pedals and doing the high power
low rpm thing!

I can relate to that. I was just in Switzerland for a week
for a conference - only got to do half a day's cycling on a
hired mtb and that too on the road - but I still had to get
down onto the small ring going up a relatively short and not
particularly steep mountain road, compared to some of the
passes I might hope to do with a loaded bike this summer. It
made me seriously wonder whether even the 30x32 I had
planned to be using is going to be low enough, or whether I
should give up now!

Rich

"Richard Goodman" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

It made me seriously wonder whether even the 30x32 I had
planned to be using is going to be low enough, or whether
I should give up now!

Perhaps you should but the back sprockets on the front and
the front on the back :-)

--
Mike W

Zog The Undeniable said:

39x25 will get you up most things

With how much comfort and pleasure? Or is that nothing to do
with cycling?

~PB

"Richard Goodman" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

"Velvet" <[email hidden]> wrote in message news:Bsmnc.6257$6y2.59577492@news-
text.cableinet.net...

Quoted message said:

[censored], why is it I can't do steep hills on a 30x25
then? a 39x25 is a vaguely low-middling gear for me, not
a very lowest one. I can only imagine you get up those
hills by standing on the pedals and doing the high power
low rpm thing!

I can relate to that. I was just in Switzerland for a week
for a conference - only got to do half a day's cycling on
a hired mtb and that too on the road - but I still had to
get down onto the small ring going up a relatively short
and not particularly steep mountain road, compared to some
of the passes I might hope to do with a loaded bike this
summer. It made me seriously wonder whether even the 30x32
I had planned to be using is going to be low enough, or
whether I should give up now!

There's a reason why even the hardcore roadies in
Switzerland have triples. And you won't find a shop that
stocks any road bikes with doubles at the front unless you
look very hard.

OTOH, if 30x32 isn't low enough then nothing is going to
help.
--
Mark South Citizen of the World, Denizen of the Net <<Tiens!
Ce poulet a une grenade!

Mark South said:

OTOH, if 30x32 isn't low enough then nothing is going
to help.

There's always my 24" gear (AKA 2 feet) which has never let
me down. They are push bikes after all.

Tony ;-)

"Tony Raven" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

Mark South said:

OTOH, if 30x32 isn't low enough then nothing is going
to help.

There's always my 24" gear (AKA 2 feet) which has never
let me down. They are push bikes after all.

30x32 is slighly over 24", so yes, the 2-foot gear is the
next one down from that :-)

Mark South said:

"Tony Raven" <[email hidden]> wrote in message news:2g6ueaF4vlnjU1@uni-
berlin.de...

Quoted message said:

Mark South said:

OTOH, if 30x32 isn't low enough then nothing is going
to help.

There's always my 24" gear (AKA 2 feet) which has never
let me down. They are push bikes after all.

30x32 is slighly over 24", so yes, the 2-foot gear is the
next one down from that :-)

24.8"

Mark South said:

There's a reason why even the hardcore roadies in
Switzerland have triples. And you won't find a shop that
stocks any road bikes with doubles at the front unless you
look very hard.

OTOH, if 30x32 isn't low enough then nothing is going
to help.

I've been reading this thread with great interest, as a
novice I'm pretty clueless when it comes to some of this
technical stuff.

I do know that climbing pitch hill from the steep-side in
the surrey hills is bl**dy murder for me, but quite
rewarding when I do get to the top.

I've gone and counted the teeth on the chainring and rear
cogs and can say that:

Front chainrings 53 / 39. Rear cogs 11 through 25

What do I need to replace to move from a double to a triple?

Should I stick with my double (I am an "athletic" novice)
and just keep training greater lactate tolerance until I can
climb fast on a 39x25?

Thanks for any advice, Mark

injuryprone said:

Mark South said:

There's a reason why even the hardcore roadies in
Switzerland have triples. And you won't find a shop that
stocks any road bikes with doubles at the front unless
you look very hard.

OTOH, if 30x32 isn't low enough then nothing is going
to help.

I've been reading this thread with great interest, as a
novice I'm pretty clueless when it comes to some of this
technical stuff.

I do know that climbing pitch hill from the steep-side in
the surrey hills is bl**dy murder for me, but quite
rewarding when I do get to the top.

I've gone and counted the teeth on the chainring and rear
cogs and can say that:

Front chainrings 53 / 39. Rear cogs 11 through 25

What do I need to replace to move from a double to a
triple?

Should I stick with my double (I am an "athletic" novice)
and just keep training greater lactate tolerance until I
can climb fast on a 39x25?

Thanks for any advice, Mark

You'll need new

triple chainset bottom bracket shifters (unless you already
have some that a double/triple compatible, Ultegra STi are)
front mech

you should but don't have to get

new gear cable new chain

Its up to you how much comfort you want. If you can manage
all hills that you want to ride then why change. If you
want to ride further and find you can't because the hills
are taking too much out of you then go triple, thats what I
have done.

On Sun, 09 May 2004 09:02:25 GMT, Velvet <[email hidden]>

wrote in message : said:

[censored], why is it I can't do steep hills on a
30x25 then?

Not enough EPO?

Guy
--
May contain traces of irony. Contents liable to settle after posting.
chapmancentral.co.ukchapmancentral.co.ukOpen ↗

88% of helmet statistics are made up, 65% of them at Washington University

Just zis Guy said:

On Sun, 09 May 2004 09:02:25 GMT, Velvet
<[email hidden]> wrote in message <Bsmnc.6257$6y2.59577492@news-
text.cableinet.net>:

Quoted message said:

[censored], why is it I can't do steep hills on a
30x25 then?

Not enough EPO?

Hmm :-) I always translate that as 'Evening Primrose Oil' -
since the EPO abbreviation's meant that to me for far longer
than anything to do with cycling...

--

Velvet

On Sun, 09 May 2004 18:06:21 GMT, Velvet <[email hidden]>

wrote in message : said:

Quoted message said:

Quoted message said:

[censored], why is it I can't do steep hills on a
30x25 then?

Not enough EPO?

Quoted message said:

Hmm :-) I always translate that as 'Evening Primrose Oil' -
since the EPO abbreviation's meant that to me for far
longer than anything to do with cycling...

That'll be why I'm not as fast as Lance, then. I'm off to
the Body Shop...

Guy
--
May contain traces of irony. Contents liable to settle after posting.
chapmancentral.co.ukchapmancentral.co.ukOpen ↗

88% of helmet statistics are made up, 65% of them at Washington University

Just zis Guy said:

That'll be why I'm not as fast as Lance, then. I'm off to
the Body Shop...

Save your time Guy, they just look puzzled and sorry for you
if you say you'd like to buy a new body ;-)

Tony