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Date: 21 May 2007 06:24:40
From: BobT
Subject: Cross Chaining
The post above about chainline and a triple chainring caused to think about
this question:

Why is cross chaining bad?

It is easy to find many admonitions to avoid it at all costs. For example:
"Cross chaining - a real don't for a properly functioning bike." The reasons
given are usually excessive gear and chain wear.

Is this really important or is this just conventional wisdom?

I generally try to avoid excessive cross chaining with my Shimano 10 speed /
triple setup because it is usually not necessary and I have read that this
is "proper shifting technique". Yet when I shift to largest chainring /
largest cog or smallest chainring / smallest cog, nothing bad seems to
happen (at least in the short term). There is no noise, the system seems to
work and shift in and out of these combinations without a hitch.

If riding in the maximal cross chain gear selection is wearing my chain out
a little faster, I really do not care very much. If it really wears out my
gears quickly, that would be of much more concern.

Is there any science on the answer to this question? Will the chain on my
brand new touring bike with internal gear hub and "perfect" chainline really
last much longer than the chain on my racing bike with 10 speed / triple if
I ignore the conventional wisdom and cross chain a lot?

BobT






 
Date: 23 May 2007 08:00:29
From: bookieb
Subject: Re: Cross Chaining
On May 21, 8:36 pm, "russellseat...@yahoo.com"
<russellseat...@yahoo.com > wrote:
> On May 21, 12:14 pm, "Leo Lichtman" <l.licht...@worldnet.att.net>
> wrote:
>
> > Someone here, a while back, presented a justification for cross-chaining,
> > based on convenience and quickness of making the shift.
>
> Might have been me. When racing up a hill with a pack, you can't drop
> to the inner chainring on a double, and probably do a shift in back
> too, and maintain fluid motion. The people behind you will run into
> you when you momentarily slow down from shfting the front derailleur.
>
<snip >

OK, I'll give you that when you're racing, or even trying to hang on
at the back of the club chain gang (...a situation that's fairly
familiar to me).
Otherwise, I avoid crossing excesively

I often think that lots of riders ride with too small a range in their
cogs, e.g. 11-23, where an 11-25 or 12-27 might suit them better.
You get just that little extra spread of gears before you have to
change chainring, for little loss other than a few more 2-3 tooth
jumps in place of 1-2 tooth jumps in the middle of the casette. The
granny gear is also a little lower.

If you're racing, and really fluid changes are vital, sure, those
small steps between cogs are important.
If you ride in an area that's flat enough (or you're strong enough)
never to need a lower bottom cog, that's cool too.
I think though, that for the majority of commuting and recreational
cyclists, the advantages of the wider cog range outweigh the
disadvantages, and it reduces the time when you're temtpted towards
cross-chaining.

On the other hand, that corn-cob and short cage rear mech sure do look
the part, and after all, that's what's important eh? :-)

regards,

bookieb.



 
Date: 21 May 2007 19:39:23
From: A Muzi
Subject: Re: Cross Chaining
BobT wrote:
> The post above about chainline and a triple chainring caused to think about
> this question:
>
> Why is cross chaining bad?
>
> It is easy to find many admonitions to avoid it at all costs. For example:
> "Cross chaining - a real don't for a properly functioning bike." The reasons
> given are usually excessive gear and chain wear.
>
> Is this really important or is this just conventional wisdom?
>
> I generally try to avoid excessive cross chaining with my Shimano 10 speed /
> triple setup because it is usually not necessary and I have read that this
> is "proper shifting technique". Yet when I shift to largest chainring /
> largest cog or smallest chainring / smallest cog, nothing bad seems to
> happen (at least in the short term). There is no noise, the system seems to
> work and shift in and out of these combinations without a hitch.
>
> If riding in the maximal cross chain gear selection is wearing my chain out
> a little faster, I really do not care very much. If it really wears out my
> gears quickly, that would be of much more concern.
>
> Is there any science on the answer to this question? Will the chain on my
> brand new touring bike with internal gear hub and "perfect" chainline really
> last much longer than the chain on my racing bike with 10 speed / triple if
> I ignore the conventional wisdom and cross chain a lot?

The admonitions are an historic version of "CYA" ; We advise against
riding in cross gears because we don't want to listen to whining about
chain noise.
When everything is correctly set up the downsides are slight - various
noises such as chain rubbing a chainring, etc.

When it's less that perfect, all sorts of trouble ensues. A beyond-spec
rear changer with chain sag can easily slip the chain off the lower
roller in small-small, making a convoluted art object out of your
changer and wrecking the chain and risking a cracked frame end. In
large-large a beyond capacity changer with short chain can again crack
in two and/or wreck the frame end.

Even acceptably assembled well adjusted new systems will often clatter
in one or both cross gears; Our assembly standard for new bikes ignores
such noises unless they occur in the second cog as well.

If your bike works well in all combinations, enjoy! You may find however
that a similar ratio exists at one of more other points in the system.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971


 
Date: 21 May 2007 12:36:26
From: russellseaton1@yahoo.com
Subject: Re: Cross Chaining
On May 21, 12:14 pm, "Leo Lichtman" <l.licht...@worldnet.att.net >
wrote:
> Someone here, a while back, presented a justification for cross-chaining,
> based on convenience and quickness of making the shift.

Might have been me. When racing up a hill with a pack, you can't drop
to the inner chainring on a double, and probably do a shift in back
too, and maintain fluid motion. The people behind you will run into
you when you momentarily slow down from shfting the front derailleur.




Since the cross
> position produces a ratio that can be matched by a middle position, there is
> no reason to stay crossed very long, and three reasons not to.
> 1.) It's handier to have the freedom to shift up or down with a single
> click.
> 2.) Wear is a function of time, so if there is more rapid wear, why not
> minimize it?
> 3.) The chain must be slightly more efficient when it is pulling straighter.




 
Date: 21 May 2007 11:13:31
From: Ozark Bicycle
Subject: Re: Cross Chaining
On May 21, 11:46 am, Guy F. Anderson Sr. <gande...@toast.net > wrote:
> On Mon, 21 May 2007 06:24:40 -0500, "BobT" <>
>
> >Why is cross chaining bad?
> >Is this really important or is this just conventional wisdom?
>
> Believe it or not, the June issue of Bicycling Magazine says that
> cross-chaining is OK, given the "flexible chains, ultra-hardy modern
> metals, and anti-friction treatments" of today's 10 speed setups. And
> they cite Shimano spokesperson Devin Walton as the source for this
> debunking of the convention that it's bad to cross-chain!


A look at the price of replacement chainrings and cassettes will
quickly expose the thinking behind Shimano's position! Helps make up
for all that stuff thay sell cheap to the OEMs.

>
> As for me, I will continue to avoid cross-chaining.


As will I.



 
Date: 21 May 2007 10:53:49
From: Hank Wirtz
Subject: Re: Cross Chaining
On May 21, 9:46 am, Guy F. Anderson Sr. <gande...@toast.net > wrote:
> On Mon, 21 May 2007 06:24:40 -0500, "BobT" <>
>
> >Why is cross chaining bad?
> >Is this really important or is this just conventional wisdom?
>
> Believe it or not, the June issue of Bicycling Magazine says that
> cross-chaining is OK, given the "flexible chains, ultra-hardy modern
> metals, and anti-friction treatments" of today's 10 speed setups. And
> they cite Shimano spokesperson Devin Walton as the source for this
> debunking of the convention that it's bad to cross-chain!
>
> As for me, I will continue to avoid cross-chaining.

I's gonna say - Who do you trust more than Bicycling Magazine and a
Shimano Spokesman?

Who DON'T you trust more?




 
Date: 21 May 2007 11:46:55
From: Guy F. Anderson Sr.
Subject: Re: Cross Chaining
On Mon, 21 May 2007 06:24:40 -0500, "BobT" < >
>Why is cross chaining bad?

>Is this really important or is this just conventional wisdom?

Believe it or not, the June issue of Bicycling Magazine says that
cross-chaining is OK, given the "flexible chains, ultra-hardy modern
metals, and anti-friction treatments" of today's 10 speed setups. And
they cite Shimano spokesperson Devin Walton as the source for this
debunking of the convention that it's bad to cross-chain!

As for me, I will continue to avoid cross-chaining.


  
Date: 21 May 2007 17:14:31
From: Leo Lichtman
Subject: Re: Cross Chaining
Someone here, a while back, presented a justification for cross-chaining,
based on convenience and quickness of making the shift. Since the cross
position produces a ratio that can be matched by a middle position, there is
no reason to stay crossed very long, and three reasons not to.
1.) It's handier to have the freedom to shift up or down with a single
click.
2.) Wear is a function of time, so if there is more rapid wear, why not
minimize it?
3.) The chain must be slightly more efficient when it is pulling straighter.




   
Date: 22 May 2007 16:29:08
From: Paul Kopit
Subject: Re: Cross Chaining
On Mon, 21 May 2007 17:14:31 GMT, "Leo Lichtman"
<l.lichtman@worldnet.att.net > wrote:

>someone here, a while back, presented a justification for cross-chaining,
>based on convenience and quickness of making the shift.

Someone that is racing would go use the big/big in order to avoid a
downshift to the smaller ring. Losinng small difference in time may
be enough to get gapped. That might happen at the summit of a shallow
grade.


 
Date: 21 May 2007 15:27:11
From: Mike Jacoubowsky
Subject: Re: Cross Chaining
> Why is cross chaining bad?
>
> It is easy to find many admonitions to avoid it at all costs. For
> example: "Cross chaining - a real don't for a properly functioning bike."
> The reasons given are usually excessive gear and chain wear.
>
> Is this really important or is this just conventional wisdom?

If the only thing that will convince you is a scientific study, then you're
not going to be convinced, because there are none. Heck, we don't even have
scientific studies showing the effects of a clean vs dirty chain, as far as
I know.

But what I can tell you from experience is that the large/large combo is
going to wear the $#%^!~ out of your VERY expensive large chainring, due to
the almost-excessive amount of machining done to those things these days,
which is designed to let the chain more-easily derail from the large
chainring to a smaller one when needed. You're likely to see it want to
shift off the large chainring on its own much sooner than it would have
otherwise (which is the primary symptom of a very-worn large chainring).
You're also going to wear out the expensive lower derailleur pulley much
more quickly as well.

Ironically, as those items wear, your drivetrain will probably become less,
not more noisy.

--Mike-- Chain Reaction Bicycles
www.ChainReactionBicycles.com


"BobT" <RobertLeeTaylorCUT@THISSuddenLink.net > wrote in message
news:46518154$0$4014$bbae4d71@news.suddenlink.net...
> The post above about chainline and a triple chainring caused to think
> about this question:
>
> Why is cross chaining bad?
>
> It is easy to find many admonitions to avoid it at all costs. For
> example: "Cross chaining - a real don't for a properly functioning bike."
> The reasons given are usually excessive gear and chain wear.
>
> Is this really important or is this just conventional wisdom?
>
> I generally try to avoid excessive cross chaining with my Shimano 10 speed
> / triple setup because it is usually not necessary and I have read that
> this is "proper shifting technique". Yet when I shift to largest
> chainring / largest cog or smallest chainring / smallest cog, nothing bad
> seems to happen (at least in the short term). There is no noise, the
> system seems to work and shift in and out of these combinations without a
> hitch.
>
> If riding in the maximal cross chain gear selection is wearing my chain
> out a little faster, I really do not care very much. If it really wears
> out my gears quickly, that would be of much more concern.
>
> Is there any science on the answer to this question? Will the chain on my
> brand new touring bike with internal gear hub and "perfect" chainline
> really last much longer than the chain on my racing bike with 10 speed /
> triple if I ignore the conventional wisdom and cross chain a lot?
>
> BobT
>
>




 
Date: 21 May 2007 07:59:51
From: Hank Wirtz
Subject: Re: Cross Chaining
On May 21, 4:24 am, "BobT" <RobertLeeTaylor...@THISSuddenLink.net >
wrote:
> The post above about chainline and a triple chainring caused to think about
> this question:
>
> Why is cross chaining bad?
>
> It is easy to find many admonitions to avoid it at all costs. For example:
> "Cross chaining - a real don't for a properly functioning bike." The reasons
> given are usually excessive gear and chain wear.
>
> Is this really important or is this just conventional wisdom?
>
> I generally try to avoid excessive cross chaining with my Shimano 10 speed /
> triple setup because it is usually not necessary and I have read that this
> is "proper shifting technique". Yet when I shift to largest chainring /
> largest cog or smallest chainring / smallest cog, nothing bad seems to
> happen (at least in the short term). There is no noise, the system seems to
> work and shift in and out of these combinations without a hitch.
>
> If riding in the maximal cross chain gear selection is wearing my chain out
> a little faster, I really do not care very much. If it really wears out my
> gears quickly, that would be of much more concern.
>
> Is there any science on the answer to this question? Will the chain on my
> brand new touring bike with internal gear hub and "perfect" chainline really
> last much longer than the chain on my racing bike with 10 speed / triple if
> I ignore the conventional wisdom and cross chain a lot?
>
> BobT

I broke my rear derailleur once by cross-chaining. I shifted into the
small-small, the parallelogram broke without me noticing, It still was
able to shift to a bigger cog, but when I went back to a smaller cog,
the RD cage went into the spokes. Luckily, I was climbing a hill at
about 8mph, so I came to a quick stop before tearing off the hanger.

I will also insert the disclaimer that this was a Suntour Superbe Tech
RD, with an internally geared parallel linkage that looked really cool
but was so prone to breakage in this manner that they discontinued it
after one model year.

It looked really cool though - it didn't use any cable housing.

Here's a cool piece on its history: http://www.bikeman.com/content/view/743/47/

Anyway, even though it was a freak failure, that experience turned me
off to cross-chaining forever.



 
Date: 21 May 2007 13:33:35
From: Joel Mayes
Subject: Re: Cross Chaining
On 2007-05-21, BobT <RobertLeeTaylorCUT@THISSuddenLink.net > wrote:
> The post above about chainline and a triple chainring caused to think about
> this question:
>
> Why is cross chaining bad?

Off the top of my head...

1) You place stress on the chain in a direction it is not
designed to be stressed.

2) You run the risk of slicing a big chunk out of your f. deraileur if
the cross chaining causes rubbing

3) On most triples and some doubles the extremes will shift badly due to
the chain not being well aligned with the pins and ramps


Cheers

Joel
--
Human Powered Cycles


  
Date: 21 May 2007 23:20:29
From: Reid Priedhorsky
Subject: Re: Cross Chaining
On Mon, 21 May 2007 13:33:35 +0000, Joel Mayes wrote:

> On 2007-05-21, BobT <RobertLeeTaylorCUT@THISSuddenLink.net> wrote:
>> The post above about chainline and a triple chainring caused to think about
>> this question:
>>
>> Why is cross chaining bad?
>
> Off the top of my head...
>
> 1) You place stress on the chain in a direction it is not
> designed to be stressed.

That said, I think that big-big and small-small are different animals, the
reason being that for a given rear wheel torque, the big cog will have the
minimum chain tension and the small the maximum. My own intuition (IANABE,
etc.) is that big-big is fine for short periods, but small-small should be
avoided.

Also, I don't see much utility in small-small because if I'm in the small
chainring and shifting up, it's unlikely that I'll be done shifting up
once I reach the small cog, whereas I frequently shift down to large-large
and that's it.

I think the reason no one's done any scientific tests is that it's tricky
to get right and no one wants to fund it (what applications would there be
beyond bicycling?).

Finally, cross-chaining will make your cat shed more.

Take care,

Reid


  
Date: 21 May 2007 11:00:57
From: BobT
Subject: Re: Cross Chaining

"Joel Mayes" <j.mayes@invalid.invalid > wrote in message
news:slrnf537u1.ff5.j.mayes@bluebird.primrose.localdomain...
>> Why is cross chaining bad?
>
> Off the top of my head...
>
> 1) You place stress on the chain in a direction it is not
> designed to be stressed.
>
Should I care? Chains are relatively inexpensive and I know how to check
for wear and hopefully I won't use a worn out chain very much and
prematurely wear out my gears.

> 2) You run the risk of slicing a big chunk out of your f. deraileur if
> the cross chaining causes rubbing
>
My derailleurs don't rub even in the most cross-chained positions

> 3) On most triples and some doubles the extremes will shift badly due to
> the chain not being well aligned with the pins and ramps
My Shimano Ultegra 10sp / triple shifts just fine in and out of the
extremes.

On the other hand, QSPC and MJ suggest that the big / big combination will
wear out my big chainring quickly. I think I'll continue to follow the
conventional advice and avoid the extremes of cross chaining since it is
easy to avoid with just a few extra clicks of the levers.

Has anyone actually seen or experienced rapid chainring wear from what they
thought was frequent, excessive cross chaining?

BobT




 
Date: 21 May 2007 05:13:55
From: Qui si parla Campagnolo
Subject: Re: Cross Chaining
On May 21, 5:24 am, "BobT" <RobertLeeTaylor...@THISSuddenLink.net >
wrote:
> The post above about chainline and a triple chainring caused to think about
> this question:
>
> Why is cross chaining bad?

It's not 'bad', just wears things out more quickly.
>
> It is easy to find many admonitions to avoid it at all costs. For example:
> "Cross chaining - a real don't for a properly functioning bike." The reasons
> given are usually excessive gear and chain wear.
>
> Is this really important or is this just conventional wisdom?

It's only important if you don't have $100+ for a Campagnolo 53t
chainring. If you are a pro with a van full of spares and mechnics,
cross chain away.
>
> I generally try to avoid excessive cross chaining with my Shimano 10 speed /
> triple setup because it is usually not necessary and I have read that this
> is "proper shifting technique". Yet when I shift to largest chainring /
> largest cog or smallest chainring / smallest cog, nothing bad seems to
> happen (at least in the short term). There is no noise, the system seems to
> work and shift in and out of these combinations without a hitch.

yep, a well adjusted system will shift just fine.

>
> If riding in the maximal cross chain gear selection is wearing my chain out
> a little faster, I really do not care very much. If it really wears out my
> gears quickly, that would be of much more concern.

The chain coming off the big ring, towards the big cog will wear the
big ring quickly.
>
> Is there any science on the answer to this question? Will the chain on my
> brand new touring bike with internal gear hub and "perfect" chainline really
> last much longer than the chain on my racing bike with 10 speed / triple if
> I ignore the conventional wisdom and cross chain a lot?

See above. I doubt it does much to the chain but it wears rings/cogs
out quickly.
>
> BobT