Feasibility of swapping chain rings

A guy in my club swaps out his chain rings depending on the ride. 53/39
for a flattish ride or a 50/34 for climbs. He says that he doesn't
adjust anything, just swaps them out.

I've been doing more climbing lately and some of them get pretty tough
on my 53/39. (ok, most of them lol) My cassette is a 12/27T 10 speed.
We have a lot of rollers around here and I love the 53/39 for them so I
don't want to lose that.

Does changing the chain ring like that make any sense? Can you get away
with it without adjusting derailleurs or brackets?

On 21/06/13 06:28, Duane wrote:
A guy in my club swaps out his chain rings depending on the ride. 53/39
for a flattish ride or a 50/34 for climbs. He says that he doesn't
adjust anything, just swaps them out.

I've been doing more climbing lately and some of them get pretty tough
on my 53/39. (ok, most of them lol) My cassette is a 12/27T 10 speed.
We have a lot of rollers around here and I love the 53/39 for them so I
don't want to lose that.

Does changing the chain ring like that make any sense? Can you get away
with it without adjusting derailleurs or brackets?

It would depend on the capabilities of your rear der, I think.

You'd need to set it up such that the rear der could handle 53x27, yet
still wrap enough to keep chain tension for 34x12.

It might need a long cage rear der I guess. Another option would be to
use two quick links to insert a few (odd number) extra chain links when
you have the 53/39 rings on, and remove them when you have the 50/34
rings on.

--
JS

On 6/20/2013 1:28 PM, Duane wrote:
A guy in my club swaps out his chain rings depending on the ride. 53/39
for a flattish ride or a 50/34 for climbs. He says that he doesn't
adjust anything, just swaps them out.

I've been doing more climbing lately and some of them get pretty tough
on my 53/39. (ok, most of them lol) My cassette is a 12/27T 10 speed.
We have a lot of rollers around here and I love the 53/39 for them so I
don't want to lose that.

Does changing the chain ring like that make any sense?

Sure, I do it on nearly every ride, with my front derailleur and my
triple crankset 50/40/26, but 53/42/30 works too. Weight penalty
negligible, one needs to develop only a tiny bit more skill in actuating
the front derailleur.

More to your question (though my answer above is serious), most cranks
sold with 53/39 chainrings won't fit a 34, and most cranks sold with
50/34 will not have same-manufacturer 39t rings that fit. You'd need a
compact or touring crank (110 mm bolt circle) and then some aftermarket
39/53t rings that fit.

Can you get away
with it without adjusting derailleurs or brackets?

As the previous poster said, you may be able to adjust to work with both
sets of rings, though the front shifting won't be optimum; clearance for
the 53t ring will mean you'll be far above the 50t ring. Front der. are
optimized for 39-53 OR 34-50 or a triple (different shape for each), so
you'll have to compromise there too.

CAN be done, but a triple solves the posed question better.
50/40/26 by 12-25 10-speed cassette gives all the flat road gears you'd
want and low enough gears for the 10%+ climbs around here.

Mark J.

On Thursday, June 20, 2013 6:06:46 PM UTC-4, James wrote:
On 21/06/13 06:28, Duane wrote:

A guy in my club swaps out his chain rings depending on the ride. 53/39

for a flattish ride or a 50/34 for climbs. He says that he doesn't

adjust anything, just swaps them out.



I've been doing more climbing lately and some of them get pretty tough

on my 53/39. (ok, most of them lol) My cassette is a 12/27T 10 speed.

We have a lot of rollers around here and I love the 53/39 for them so I

don't want to lose that.



Does changing the chain ring like that make any sense? Can you get away

with it without adjusting derailleurs or brackets?



It would depend on the capabilities of your rear der, I think.



You'd need to set it up such that the rear der could handle 53x27, yet

still wrap enough to keep chain tension for 34x12.



It might need a long cage rear der I guess. Another option would be to

use two quick links to insert a few (odd number) extra chain links when

you have the 53/39 rings on, and remove them when you have the 50/34

rings on.

I agree with James, but I wonder about your overall choice of gear train, etc. It's certainly worthwhile to have your bike set up so you can get whatever gear you need by just shifting normally, not installing or removing parts. It's far better to have gears you seldom use (especially low ones) than to not have a low gear when you really need it.

We have the technology. In fact, we've had the technology for many decades..

- Frank Krygowski

On 6/20/2013 7:14 PM, Mark J. wrote:
On 6/20/2013 1:28 PM, Duane wrote:
A guy in my club swaps out his chain rings depending on the ride. 53/39
for a flattish ride or a 50/34 for climbs. He says that he doesn't
adjust anything, just swaps them out.

I've been doing more climbing lately and some of them get pretty tough
on my 53/39. (ok, most of them lol) My cassette is a 12/27T 10 speed.
We have a lot of rollers around here and I love the 53/39 for them so I
don't want to lose that.

Does changing the chain ring like that make any sense?

Sure, I do it on nearly every ride, with my front derailleur and my
triple crankset 50/40/26, but 53/42/30 works too. Weight penalty
negligible, one needs to develop only a tiny bit more skill in
actuating the front derailleur.

More to your question (though my answer above is serious), most cranks
sold with 53/39 chainrings won't fit a 34, and most cranks sold with
50/34 will not have same-manufacturer 39t rings that fit. You'd need
a compact or touring crank (110 mm bolt circle) and then some
aftermarket 39/53t rings that fit.

Can you get away
with it without adjusting derailleurs or brackets?

As the previous poster said, you may be able to adjust to work with
both sets of rings, though the front shifting won't be optimum;
clearance for the 53t ring will mean you'll be far above the 50t
ring. Front der. are optimized for 39-53 OR 34-50 or a triple
(different shape for each), so you'll have to compromise there too.

CAN be done, but a triple solves the posed question better.
50/40/26 by 12-25 10-speed cassette gives all the flat road gears
you'd want and low enough gears for the 10%+ climbs around here.

Mark J.


Thanks. I have another bike with a triple that I could use for a tough
climb. Might be a reason to get it out of moth balls.

On 6/20/2013 6:06 PM, James wrote:
On 21/06/13 06:28, Duane wrote:
A guy in my club swaps out his chain rings depending on the ride. 53/39
for a flattish ride or a 50/34 for climbs. He says that he doesn't
adjust anything, just swaps them out.

I've been doing more climbing lately and some of them get pretty tough
on my 53/39. (ok, most of them lol) My cassette is a 12/27T 10 speed.
We have a lot of rollers around here and I love the 53/39 for them so I
don't want to lose that.

Does changing the chain ring like that make any sense? Can you get away
with it without adjusting derailleurs or brackets?
It would depend on the capabilities of your rear der, I think.

You'd need to set it up such that the rear der could handle 53x27, yet
still wrap enough to keep chain tension for 34x12.

It might need a long cage rear der I guess. Another option would be to
use two quick links to insert a few (odd number) extra chain links when
you have the 53/39 rings on, and remove them when you have the 50/34
rings on.


Guy at the LBS said he wouldn't advise trying to just switch the chain
rings for the reason that both you and Mark point out. He suggested
that I try one of the newish 52/36 mid compacts. I may test drive one
but I really like the 53/39 most of the time so maybe the answer is more
squats at the gym.

On 21/06/13 10:17, Duane Hébert wrote:
On 6/20/2013 6:06 PM, James wrote:
On 21/06/13 06:28, Duane wrote:
A guy in my club swaps out his chain rings depending on the ride. 53/39
for a flattish ride or a 50/34 for climbs. He says that he doesn't
adjust anything, just swaps them out.

I've been doing more climbing lately and some of them get pretty tough
on my 53/39. (ok, most of them lol) My cassette is a 12/27T 10 speed.
We have a lot of rollers around here and I love the 53/39 for them so I
don't want to lose that.

Does changing the chain ring like that make any sense? Can you get away
with it without adjusting derailleurs or brackets?
It would depend on the capabilities of your rear der, I think.

You'd need to set it up such that the rear der could handle 53x27, yet
still wrap enough to keep chain tension for 34x12.

It might need a long cage rear der I guess. Another option would be to
use two quick links to insert a few (odd number) extra chain links when
you have the 53/39 rings on, and remove them when you have the 50/34
rings on.


Guy at the LBS said he wouldn't advise trying to just switch the chain
rings for the reason that both you and Mark point out. He suggested
that I try one of the newish 52/36 mid compacts. I may test drive one
but I really like the 53/39 most of the time so maybe the answer is more
squats at the gym.


How about a special rear wheel with a 2 or 3 speed IGH + cassette ;-)

--
JS

On 21/06/13 15:54, Phil W Lee wrote:
James considered Fri, 21 Jun 2013 10:45:34
+1000 the perfect time to write:

On 21/06/13 10:17, Duane Hébert wrote:
On 6/20/2013 6:06 PM, James wrote:
On 21/06/13 06:28, Duane wrote:
A guy in my club swaps out his chain rings depending on the ride. 53/39
for a flattish ride or a 50/34 for climbs. He says that he doesn't
adjust anything, just swaps them out.

I've been doing more climbing lately and some of them get pretty tough
on my 53/39. (ok, most of them lol) My cassette is a 12/27T 10 speed.
We have a lot of rollers around here and I love the 53/39 for them so I
don't want to lose that.

Does changing the chain ring like that make any sense? Can you get away
with it without adjusting derailleurs or brackets?
It would depend on the capabilities of your rear der, I think.

You'd need to set it up such that the rear der could handle 53x27, yet
still wrap enough to keep chain tension for 34x12.

It might need a long cage rear der I guess. Another option would be to
use two quick links to insert a few (odd number) extra chain links when
you have the 53/39 rings on, and remove them when you have the 50/34
rings on.


Guy at the LBS said he wouldn't advise trying to just switch the chain
rings for the reason that both you and Mark point out. He suggested
that I try one of the newish 52/36 mid compacts. I may test drive one
but I really like the 53/39 most of the time so maybe the answer is more
squats at the gym.


How about a special rear wheel with a 2 or 3 speed IGH + cassette ;-)

You mean a standard SRAM DualDrive?
Available in 3x8 or 3x9.

I'm not convinced of SRAM engineering, but YMMV. I hear stories and
read of breakages - not of that particular part, but still.

--
JS

On Thursday, 20 June 2013 21:28:17 UTC+1, Duane wrote:
A guy in my club swaps out his chain rings depending on the ride. 53/39

for a flattish ride or a 50/34 for climbs. He says that he doesn't

adjust anything, just swaps them out.



I've been doing more climbing lately and some of them get pretty tough

on my 53/39. (ok, most of them lol) My cassette is a 12/27T 10 speed.

We have a lot of rollers around here and I love the 53/39 for them so I

don't want to lose that.



Does changing the chain ring like that make any sense? Can you get away

with it without adjusting derailleurs or brackets?

I say, use the bike with the triple until you are fitter or have a clearer idea of exactly what gear ratios you need. At least SRAM have cassettes with big sprockets so that you can team that up with a dual chainring. Usually I have found that 39front x 28 rear to be satisfactory for an otherwise unladen bike as long as I am fully recovered and I gear appropriately at all times through the day. So take it easy and enjoy the ride. If your mate is relentless in pushing the pace, stop and have a picnic (let him go) or go find another mate.

On Thursday, June 20, 2013 9:28:17 PM UTC+1, Duane wrote:
A guy in my club swaps out his chain rings depending on the ride. 53/39

for a flattish ride or a 50/34 for climbs. He says that he doesn't

adjust anything, just swaps them out.



I've been doing more climbing lately and some of them get pretty tough

on my 53/39. (ok, most of them lol) My cassette is a 12/27T 10 speed.

We have a lot of rollers around here and I love the 53/39 for them so I

don't want to lose that.



Does changing the chain ring like that make any sense? Can you get away

with it without adjusting derailleurs or brackets?

May be smarter to fit a triple and save yourself the constant swapping of chainrings. I imagine you use alloy chainring bolts and those things will wear out pretty fast.

Anyway, where will you get the chainrings in the tooth counts you want that fit the same (road) crank? You might have to change cranks, possibly to the 110mm PCD type, which has a really wide range of rings available, because it is the go-to format for utility and touring cycles which have wide load requirements and are traditionally fitted with big gearing ranges.

One advantage of these touring cranks is that many of them are beautiful (unlike for instance the ugly stuff sold to downhillers in the 104/64 PCD format). I use a Sugino Cospea branded by Stronglight which is very beautiful but there are other Sugino, especially the XD2, available at really attractive prices, including with TA rings, especially if you don't insist on a famous brand name on the cranks.

Sugino XD2:

Custom TA rings:
http://www.spacycles.co.uk/products....=m2b0s109p2004
If one of their choices of TA rings suit:
http://www.spacycles.co.uk/products....=m2b0s109p2002
With Stronglight rings at an amazing price: :
http://www.spacycles.co.uk/products.php?plid=m2b0s109p3
More on this page:
http://www.spacycles.co.uk/products.php?plid=m2b0s109p0

The thing with Spa is to check with John what the carriage will be before you start window-shopping. There's been a report within the last week from Anto Kelly on the Thorn board that Spa's postage has come down and sounded very reasonable.

Same XD2 from Thorn, known to deliver to the USA, one of Sheldon's faves, but no choice in the rings, though for a cost they will no doubt swap out rings for you from their huge stock, though their really special rings is their own cut of touring rings, maybe a bit heavy for road use, though they last forever, and are then reversible:
http://www.sjscycles.co.uk/stronglig...28t-prod18493/

Here's another company I can recommend for excellent prices and service (I shop with them all the time) that stocks the Impact, including the prettier (than the XD2) Cospea version in some of the range:
http://www.xxcycle.com/crankset-stro...triple,,en.php
Fancier Z-Light cranks towards the bottom of the page if you're feeling spendier:
http://www.xxcycle.com/crankset-stro...triple,,en.php

BTW, if you have to change BB, the Stronglight JP400 touted as good with the Impact cranks is the Czech Kinex commonly fitted to bikes for the Euro-elite, a super-quality item at half the price of a Shimano.

Don't be deterred by the Cospea's lightweight looks: to make up the tensile strength, Sugino cold-forged it, whereas the beefier XD2 is hot-forged.

I use an Impact Compact Double with only one ring on it, in the Cospea version (pic http://www.thorncycles.co.uk/forums/...19603#msg19603 at bottom of post), because that was the best quality/price point of an aesthetically pleasing crank I found -- it took me bloody years to find a crank that would fit my very wide bike that wasn't butt-ugly. I removed the Stronglight rings because I use a Surly stainless chainring.

If you insist on a very narrow tread, check the Impact Q-factor before you splash out the money, because it isn't among the narrowest.

Andre Jute