broken rear derailleur, limp home as single speed?

[Kerry Montgomery]

Hi all,
I've carried a chain tool with me for years in case I break a chain or rear
derailleur and have to shorten the chain to get home. Yesterday came across
a guy with a broken rear derailleur. Shortened the chain, and got it to fit,
and track, from the middle front to the 2nd or 3rd lowest rear sprocket. A
little tight, but rideable. With the vertical dropouts on his bike, did I
just get lucky with the fit? Is there some additional technique that would
make it more likely that a shortened chain will work on a bike with vertical
dropouts? When I started carrying the chain tool, my bike had horizontal
dropouts, but the current bike has vertical ones. Am I fooling myself about
the likelihood of being able to limp home if I break the rear derailleur on
my bike?
Thanks,
Kerry

 

[[email protected]]

On Jul 9, 5:02 pm, "Kerry Montgomery" <[email protected]> wrote:
> Hi all,
> I've carried a chain tool with me for years in case I break a chain or rear
> derailleur and have to shorten the chain to get home. Yesterday came across
> a guy with a broken rear derailleur. Shortened the chain, and got it to fit,
> and track, from the middle front to the 2nd or 3rd lowest rear sprocket. A
> little tight, but rideable. With the vertical dropouts on his bike, did I
> just get lucky with the fit? Is there some additional technique that would
> make it more likely that a shortened chain will work on a bike with vertical
> dropouts? When I started carrying the chain tool, my bike had horizontal
> dropouts, but the current bike has vertical ones. Am I fooling myself about
> the likelihood of being able to limp home if I break the rear derailleur on
> my bike?
> Thanks,
> Kerry

Dear Kerry,

http://i16.tinypic.com/4gj8g2c.jpg



Actually, there's a fixed metal finger just below the rear sprocket
that keeps the chain wrapped around the teeth:

http://groups.google.com/group/rec.bicycles.tech/msg/8bbb780d95afc188

Cheers,

Carl Fogel

 

[Joel Mayes]

On 2007-07-09, Kerry Montgomery <[email protected]> wrote:
> Hi all,
> I've carried a chain tool with me for years in case I break a chain or rear
> derailleur and have to shorten the chain to get home. Yesterday came across
> a guy with a broken rear derailleur. Shortened the chain, and got it to fit,
> and track, from the middle front to the 2nd or 3rd lowest rear sprocket. A
> little tight, but rideable. With the vertical dropouts on his bike, did I
> just get lucky with the fit? Is there some additional technique that would
> make it more likely that a shortened chain will work on a bike with vertical
> dropouts? When I started carrying the chain tool, my bike had horizontal
> dropouts, but the current bike has vertical ones. Am I fooling myself about
> the likelihood of being able to limp home if I break the rear derailleur on
> my bike?
> Thanks,
> Kerry

With a modern close ratio cassette I'd be suprised if you couldn't find
a working SS gear. If you're really worried you could carry a
half link around.

Cheers

Joel

--
Human Powered Cycles | High quality servicing and repairs
[email protected] | Affordable second hand bikes
(03) 9029 6504 | Bicycle reuse centre
www.humanpowered.com.au | Mechanical and on-road training and instruction

 

[Nate Knutson]

On Jul 9, 4:23 pm, Joel Mayes <[email protected]> wrote:
> On 2007-07-09, Kerry Montgomery <[email protected]> wrote:
>
> > Hi all,
> > I've carried a chain tool with me for years in case I break a chain or rear
> > derailleur and have to shorten the chain to get home. Yesterday came across
> > a guy with a broken rear derailleur. Shortened the chain, and got it to fit,
> > and track, from the middle front to the 2nd or 3rd lowest rear sprocket. A
> > little tight, but rideable. With the vertical dropouts on his bike, did I
> > just get lucky with the fit? Is there some additional technique that would
> > make it more likely that a shortened chain will work on a bike with vertical
> > dropouts? When I started carrying the chain tool, my bike had horizontal
> > dropouts, but the current bike has vertical ones. Am I fooling myself about
> > the likelihood of being able to limp home if I break the rear derailleur on
> > my bike?
> > Thanks,
> > Kerry
>
> With a modern close ratio cassette I'd be suprised if you couldn't find
> a working SS gear. If you're really worried you could carry a
> half link around.

I am theorizing because I don't have a 3/32" half link handy, but I
don't think a half link would work here, as it would catch on adjacent
cogs. 3/32" halflinks are still only intended for SS use. Also, the
"inner link" half of it probably wouldn't fit very happily between the
"outer link" parts of any typical modern derailer chain.

 

[Paul Myron Hobson]

Nate Knutson wrote:
> I am theorizing because I don't have a 3/32" half link handy, but I
> don't think a half link would work here, as it would catch on adjacent
> cogs. 3/32" halflinks are still only intended for SS use. Also, the
> "inner link" half of it probably wouldn't fit very happily between the
> "outer link" parts of any typical modern derailer chain.

In my SS experience, half-links work fine with 8spd chains. I agree
that 9 and 10spd chains are probably out of the question.

\\paul

 

[Kerry Montgomery]

"Paul Myron Hobson" <[email protected]> wrote in message
news:[email protected]...
> Nate Knutson wrote:
>> I am theorizing because I don't have a 3/32" half link handy, but I
>> don't think a half link would work here, as it would catch on adjacent
>> cogs. 3/32" halflinks are still only intended for SS use. Also, the
>> "inner link" half of it probably wouldn't fit very happily between the
>> "outer link" parts of any typical modern derailer chain.
>
> In my SS experience, half-links work fine with 8spd chains. I agree that
> 9 and 10spd chains are probably out of the question.
>
> \\paul
>
Shucks,
Was about to order a half link, but the bike's a 9 speed.
Thanks for the info,
Kerry

 

[Kerry Montgomery]

<[email protected]> wrote in message
news:[email protected]...
> On Jul 9, 5:02 pm, "Kerry Montgomery" <[email protected]> wrote:
>> Hi all,
>> I've carried a chain tool with me for years in case I break a chain or
>> rear
>> derailleur and have to shorten the chain to get home. Yesterday came
>> across
>> a guy with a broken rear derailleur. Shortened the chain, and got it to
>> fit,
>> and track, from the middle front to the 2nd or 3rd lowest rear sprocket.
>> A
>> little tight, but rideable. With the vertical dropouts on his bike, did I
>> just get lucky with the fit? Is there some additional technique that
>> would
>> make it more likely that a shortened chain will work on a bike with
>> vertical
>> dropouts? When I started carrying the chain tool, my bike had horizontal
>> dropouts, but the current bike has vertical ones. Am I fooling myself
>> about
>> the likelihood of being able to limp home if I break the rear derailleur
>> on
>> my bike?
>> Thanks,
>> Kerry
>
> Dear Kerry,
>
> http://i16.tinypic.com/4gj8g2c.jpg
>
>
>
> Actually, there's a fixed metal finger just below the rear sprocket
> that keeps the chain wrapped around the teeth:
>
> http://groups.google.com/group/rec.bicycles.tech/msg/8bbb780d95afc188
>
> Cheers,
>
> Carl Fogel
>
Carl,
Ah yes, Vernon "never back pedal" Blake.
Thanks,
Kerry

 

[A Muzi]

>> Nate Knutson wrote:
>>> I am theorizing because I don't have a 3/32" half link handy, but I
>>> don't think a half link would work here, as it would catch on adjacent
>>> cogs. 3/32" halflinks are still only intended for SS use. Also, the
>>> "inner link" half of it probably wouldn't fit very happily between the
>>> "outer link" parts of any typical modern derailer chain.

> "Paul Myron Hobson" <[email protected]> wrote
>> In my SS experience, half-links work fine with 8spd chains. I agree that
>> 9 and 10spd chains are probably out of the question.

Kerry Montgomery wrote:
> Was about to order a half link, but the bike's a 9 speed.

I'm pretty sure the only available half links for 3/32 chain are 7.3mm
(seven speed format)

--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971

 

[Paul Myron Hobson]

A Muzi wrote:
>>> Nate Knutson wrote:
>>>> I am theorizing because I don't have a 3/32" half link handy, but I
>>>> don't think a half link would work here, as it would catch on adjacent
>>>> cogs. 3/32" halflinks are still only intended for SS use. Also, the
>>>> "inner link" half of it probably wouldn't fit very happily between the
>>>> "outer link" parts of any typical modern derailer chain.
>
>> "Paul Myron Hobson" <[email protected]> wrote
>>> In my SS experience, half-links work fine with 8spd chains. I agree
>>> that 9 and 10spd chains are probably out of the question.
>
> Kerry Montgomery wrote:
>> Was about to order a half link, but the bike's a 9 speed.
>
> I'm pretty sure the only available half links for 3/32 chain are 7.3mm
> (seven speed format)

Oh. hmmm. whoops.
\\paul (coulda sworn...)

 

[* * Chas]

"Kerry Montgomery" <[email protected]> wrote in message
news:[email protected]...
> Hi all,
> I've carried a chain tool with me for years in case I break a chain or
rear
> derailleur and have to shorten the chain to get home. Yesterday came
across
> a guy with a broken rear derailleur. Shortened the chain, and got it to
fit,
> and track, from the middle front to the 2nd or 3rd lowest rear sprocket.
A
> little tight, but rideable. With the vertical dropouts on his bike, did
I
> just get lucky with the fit? Is there some additional technique that
would
> make it more likely that a shortened chain will work on a bike with
vertical
> dropouts? When I started carrying the chain tool, my bike had horizontal
> dropouts, but the current bike has vertical ones. Am I fooling myself
about
> the likelihood of being able to limp home if I break the rear derailleur
on
> my bike?
> Thanks,
> Kerry
>
>

I always carried a small Cyclo chain tool and a spoke wrench and long
rides and tours. Had to use it to fix other's bikes a few times.

Vertical dropouts do pose a little problem but back in the day, I've seen
people riding beat up junker bikes with totally worn out chains with 1/2"
+ slack in the top run.

Chas.

 

[A Muzi]

* * Chas wrote:
> Vertical dropouts do pose a little problem but back in the day, I've seen
> people riding beat up junker bikes with totally worn out chains with 1/2"
> + slack in the top run.

Slack on top? Charles, we've told you a million times not to exaggerate.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971

 

[[email protected]]

On Tue, 10 Jul 2007 16:09:00 -0500, A Muzi <[email protected]>
wrote:

>* * Chas wrote:
>> Vertical dropouts do pose a little problem but back in the day, I've seen
>> people riding beat up junker bikes with totally worn out chains with 1/2"
>> + slack in the top run.
>
>Slack on top? Charles, we've told you a million times not to exaggerate.

Dear Andrew,

I'm not sure, but I _think_ that a retro-direct drive-train involves a
relatively slack top run when it's pedaled backward:

http://www.m-gineering.nl/retrog.htm

Of course, "top run" may lose its meaning near the rear axle of such a
beast.

Cheers,

Carl Fogel

 

[* * Chas]

"A Muzi" <[email protected]> wrote in message
news:[email protected]...
> * * Chas wrote:
> > Vertical dropouts do pose a little problem but back in the day, I've
seen
> > people riding beat up junker bikes with totally worn out chains with
1/2"
> > + slack in the top run.
>
> Slack on top? Charles, we've told you a million times not to exaggerate.
> --
> Andrew Muzi
> www.yellowjersey.org
> Open every day since 1 April, 1971

When they stopped pedaling gravity took over....

Chas.

 

[* * Chas]

"A Muzi" <[email protected]> wrote in message
news:[email protected]...
> * * Chas wrote:
> > Vertical dropouts do pose a little problem but back in the day, I've
seen
> > people riding beat up junker bikes with totally worn out chains with
1/2"
> > + slack in the top run.
>
> Slack on top? Charles, we've told you a million times not to exaggerate.
> --
> Andrew Muzi
> www.yellowjersey.org
> Open every day since 1 April, 1971

Let me rephrase this. When I was young (in the 1950's) I remember seeing
coaster brake bikes with chains so worn the they sagged in the middle on
the top run when not being pedaled.

Chas. the exaggerator....

 

[[email protected]]

On Jul 10, 8:36 am, "Kerry Montgomery" <[email protected]> wrote:
> "Paul Myron Hobson" <[email protected]> wrote :
> Nate Knutson wrote:
> >> I am theorizing because I don't have a 3/32" half link handy, but I
> >> don't think a half link would work here, as it would catch on adjacent
> >> cogs. 3/32" halflinks are still only intended for SS use. Also, the
> >> "inner link" half of it probably wouldn't fit very happily between the
> >> "outer link" parts of any typical modern derailer chain.
>
> > In my SS experience, half-links work fine with 8spd chains. I agree that
> > 9 and 10spd chains are probably out of the question.
>
> Was about to order a half link, but the bike's a 9 speed.

You can't fix every eventuality 100%. Carrying a chain tool
is worthwhile because it is hard to improvise one. However,
if you can't fix the bike to shop-standards of chain tension,
that doesn't really matter. The goal is just to limp home.

I once hit a derailleur-stick that broke my rear der into multiple
pieces, bent the hanger and also the seatstay and dropout,
bent the rear axle and damaged the wheel. I was able to
shorten the chain and ride home - it was a horizontal-dropout
bike, but because everything was bent, the chain kept
climbing onto the next cog and jamming. It still was better
than walking.

(BTW, Tom Sullivan of Amsterdam Bicycles straightened
out the [steel] frame and it's still rideable today.)

Ben

 

[Peter Cole]

[email protected] wrote:

> I once hit a derailleur-stick that broke my rear der into multiple
> pieces, bent the hanger and also the seatstay and dropout,
> bent the rear axle and damaged the wheel. I was able to
> shorten the chain and ride home - it was a horizontal-dropout
> bike, but because everything was bent, the chain kept
> climbing onto the next cog and jamming. It still was better
> than walking.

The one time I tried this the same thing happened, unfortunately it was
a frame with vertical dropouts. The chain jammed, I had to walk the bike
and even destroyed a chain tool removing the chain at home.

 

[AWN]

I had the same thing happen a few weeks ago. The RD hit the spokes and was
obliterated as it also took out a dozen spokes before the wheel bent the
dropouts. Anyway, I straightened the wheel on a rock, put the RD in my
pack, removed a good section of chain and we were able to ride out also for
another hour. I couldn't get than wheel to spin without rubbig the frame on
the Superlite no matter what I tried. I ended up swapping the hammered
wheel on my Kona because it has spacing for larger wheels. My friend had
ghosted gearing with a good wheel and I had a toasted wheel with most of the
spoked wrapped around the next. We were quite a pair that day....
Andrew.






in article [email protected],
[email protected] at [email protected] wrote on 7/11/07 3:27 AM:

> On Jul 10, 8:36 am, "Kerry Montgomery" <[email protected]> wrote:
>> "Paul Myron Hobson" <[email protected]> wrote :
>> Nate Knutson wrote:
>>>> I am theorizing because I don't have a 3/32" half link handy, but I
>>>> don't think a half link would work here, as it would catch on adjacent
>>>> cogs. 3/32" halflinks are still only intended for SS use. Also, the
>>>> "inner link" half of it probably wouldn't fit very happily between the
>>>> "outer link" parts of any typical modern derailer chain.
>>
>>> In my SS experience, half-links work fine with 8spd chains. I agree that
>>> 9 and 10spd chains are probably out of the question.
>>
>> Was about to order a half link, but the bike's a 9 speed.
>
> You can't fix every eventuality 100%. Carrying a chain tool
> is worthwhile because it is hard to improvise one. However,
> if you can't fix the bike to shop-standards of chain tension,
> that doesn't really matter. The goal is just to limp home.
>
> I once hit a derailleur-stick that broke my rear der into multiple
> pieces, bent the hanger and also the seatstay and dropout,
> bent the rear axle and damaged the wheel. I was able to
> shorten the chain and ride home - it was a horizontal-dropout
> bike, but because everything was bent, the chain kept
> climbing onto the next cog and jamming. It still was better
> than walking.
>
> (BTW, Tom Sullivan of Amsterdam Bicycles straightened
> out the [steel] frame and it's still rideable today.)
>
> Ben
>
>