Rear Derailleur

On Tuesday, May 11, 2021 at 6:56:30 AM UTC-7, AMuzi wrote:
On 5/11/2021 8:41 AM, Tom Kunich wrote:
On Monday, May 10, 2021 at 7:09:57 PM UTC-7, Frank Krygowski wrote:
On 5/10/2021 9:42 PM, AMuzi wrote:
On 5/10/2021 8:22 PM, jbeattie wrote:
On Monday, May 10, 2021 at 4:51:13 PM UTC-7, wrote:
On Monday, May 10, 2021 at 4:19:53 PM UTC-7, jbeattie wrote:
On Monday, May 10, 2021 at 9:59:14 AM UTC-7, wrote:
I did a climbing ride sort of - it was less that 1000 feet and the
steepest part was only about 9%. For some reason I was dog tired
and it really hurt.

3/4ths of the way in to the ride and luckily downhill to most
extent, the rear derailleur idler pully exploded. I assumed that it
was the roller bearing idler pulley but working on it what happened
was the the sheet metal rotational limit piece on the derailleur
appears to have broken off which caused the pulley to be pulled
into the cassette which broke it and this entire thing locked up
the whole drive train which bent the drop out. So I have to get a
replacement for that. After removing the rear derailleur it will
not thread back in.

Finding a replacement ought to be a whole lot of fun.
It sounds like you pulled the guide pulley into the cassette and the
other damage followed and not vice versa. That can happen under
certain unfortunate circumstances.

The rear derailleur cannot be "pulled into the cassette" though that
is what I thought too.

Sure it can, and it happens with fair regularity on MTBs. It can be
a b-screw screw-up, limit screw screw-up, worn chain, cassette,
chainrings -- a stick, rock. It can even be caused by a shift and a
bump. I have never heard of the b-screw tab breaking, but maybe that
happens on Campy derailleurs -- and if so, that is a major design FU,
particularly considering the consequences.

Until I analyzed it. The stop on the rear derailleur with is a small
sheet steel washer-like mechanism that keeps the derailleur from
rotating past the stop. Without that stop the idler pulley was pulled
into the cassette and the entire mechanism was locked up solid.

FYI, your typical pully choices are "upper or lower" or "guide pulley"
(upper) or "tension pulley." (lower). I don't know what an idler
pulley is on a derailleur.

-- Jay Beattie.


And it's simple to avoid.
Finish any gear adjustment with this test:
http://www.yellowjersey.org/photosfr...t/gearchek.jpg

image from Canada, miketechinfo.com
I think Tom needs to hire a better mechanic. It seems like about a
quarter of his posts are about bike wrenching screw-ups.

And yet as a supposed mechanical engineer you don't even know how to hold an Allen wrench. I find it humorous that people who haven't seen a thing in their lives are so ready to tell others how to do things. Jay is telling us that since things happen on an MTB with a 42 tooth cassette they happen all the time on a Campy Record bike with a 28 tooth.

If it wasn't so comical you guys would be nothing more than pitiful.

Is there a 'wrong' way to hold an allen wrench? In two
tentacles rather than three? What?

Andrew, without actually seeing the problem or the initial setup people do not have the right to criticize other people's problems. Exactly how do you set up a Campy Record long arm rear derailleur with an 11-28 cassette wrongly? There was no play in the hinges of the derailleur. I have five identical setups none of which have any problems. I said that the steel stop failed. Pretty obviously this was because of metal fatigue from shifting high to low too much because most of the cogs have too close ratios. I have set up so many Di2 groups now that I've lost track. These shift absolutely perfectly and they are designed to NOT slam the derailleurs into the stops. SRAM e-Tap only allows you to shift one gear at a time to avoid this problem which is only going to become more of a problem as more gears and closer ratios are sold. I haven't looked at the new 11 Speed Campy up close but my guess is that they handle this differently since Branford Bike sells these parts separately.

On 5/11/2021 11:44 AM, Tom Kunich wrote:
On Tuesday, May 11, 2021 at 6:56:30 AM UTC-7, AMuzi wrote:
On 5/11/2021 8:41 AM, Tom Kunich wrote:
On Monday, May 10, 2021 at 7:09:57 PM UTC-7, Frank Krygowski wrote:
On 5/10/2021 9:42 PM, AMuzi wrote:
On 5/10/2021 8:22 PM, jbeattie wrote:
On Monday, May 10, 2021 at 4:51:13 PM UTC-7, wrote:
On Monday, May 10, 2021 at 4:19:53 PM UTC-7, jbeattie wrote:
On Monday, May 10, 2021 at 9:59:14 AM UTC-7, wrote:
I did a climbing ride sort of - it was less that 1000 feet and the
steepest part was only about 9%. For some reason I was dog tired
and it really hurt.

3/4ths of the way in to the ride and luckily downhill to most
extent, the rear derailleur idler pully exploded. I assumed that it
was the roller bearing idler pulley but working on it what happened
was the the sheet metal rotational limit piece on the derailleur
appears to have broken off which caused the pulley to be pulled
into the cassette which broke it and this entire thing locked up
the whole drive train which bent the drop out. So I have to get a
replacement for that. After removing the rear derailleur it will
not thread back in.

Finding a replacement ought to be a whole lot of fun.
It sounds like you pulled the guide pulley into the cassette and the
other damage followed and not vice versa. That can happen under
certain unfortunate circumstances.

The rear derailleur cannot be "pulled into the cassette" though that
is what I thought too.

Sure it can, and it happens with fair regularity on MTBs. It can be
a b-screw screw-up, limit screw screw-up, worn chain, cassette,
chainrings -- a stick, rock. It can even be caused by a shift and a
bump. I have never heard of the b-screw tab breaking, but maybe that
happens on Campy derailleurs -- and if so, that is a major design FU,
particularly considering the consequences.

Until I analyzed it. The stop on the rear derailleur with is a small
sheet steel washer-like mechanism that keeps the derailleur from
rotating past the stop. Without that stop the idler pulley was pulled
into the cassette and the entire mechanism was locked up solid.

FYI, your typical pully choices are "upper or lower" or "guide pulley"
(upper) or "tension pulley." (lower). I don't know what an idler
pulley is on a derailleur.

-- Jay Beattie.


And it's simple to avoid.
Finish any gear adjustment with this test:
http://www.yellowjersey.org/photosfr...t/gearchek.jpg

image from Canada, miketechinfo.com
I think Tom needs to hire a better mechanic. It seems like about a
quarter of his posts are about bike wrenching screw-ups.

And yet as a supposed mechanical engineer you don't even know how to hold an Allen wrench. I find it humorous that people who haven't seen a thing in their lives are so ready to tell others how to do things. Jay is telling us that since things happen on an MTB with a 42 tooth cassette they happen all the time on a Campy Record bike with a 28 tooth.

If it wasn't so comical you guys would be nothing more than pitiful.

Is there a 'wrong' way to hold an allen wrench? In two
tentacles rather than three? What?

Andrew, without actually seeing the problem or the initial setup people do not have the right to criticize other people's problems.

I'm not criticizing that specific problem. I'm criticizing your
mechanical aptitude in general. You've written an entire book here about
your mechanical mistakes, with an appendix covering your electronic
mistakes and your mis-ordered parts. You have retired the trophy for
bike wrenching incompetence.

As to holding Allen wrenches: I've built and rebuilt multiple bikes from
the frame up. I've disassembled and rebuilt multiple engines of cars,
plus motorcycles, lawn mowers and more. I'm a reasonably competent
machinist and a halfway competent welder. I've taught others how to do
those things.

I'm not claiming to be perfect. We all make mistakes. But someone who
makes as many mistakes as you should not be insulting others' mechanical
aptitude.

(And yes, we know, it's all Biden's fault. Please spare us the off-topic
political deflection nonsense.)

--
- Frank Krygowski

On Tuesday, May 11, 2021 at 9:39:56 AM UTC-7, Frank Krygowski wrote:
On 5/11/2021 11:44 AM, Tom Kunich wrote:
On Tuesday, May 11, 2021 at 6:56:30 AM UTC-7, AMuzi wrote:
On 5/11/2021 8:41 AM, Tom Kunich wrote:
On Monday, May 10, 2021 at 7:09:57 PM UTC-7, Frank Krygowski wrote:
On 5/10/2021 9:42 PM, AMuzi wrote:
On 5/10/2021 8:22 PM, jbeattie wrote:
On Monday, May 10, 2021 at 4:51:13 PM UTC-7, wrote:
On Monday, May 10, 2021 at 4:19:53 PM UTC-7, jbeattie wrote:
On Monday, May 10, 2021 at 9:59:14 AM UTC-7, wrote:
I did a climbing ride sort of - it was less that 1000 feet and the
steepest part was only about 9%. For some reason I was dog tired
and it really hurt.

3/4ths of the way in to the ride and luckily downhill to most
extent, the rear derailleur idler pully exploded. I assumed that it
was the roller bearing idler pulley but working on it what happened
was the the sheet metal rotational limit piece on the derailleur
appears to have broken off which caused the pulley to be pulled
into the cassette which broke it and this entire thing locked up
the whole drive train which bent the drop out. So I have to get a
replacement for that. After removing the rear derailleur it will
not thread back in.

Finding a replacement ought to be a whole lot of fun.
It sounds like you pulled the guide pulley into the cassette and the
other damage followed and not vice versa. That can happen under
certain unfortunate circumstances.

The rear derailleur cannot be "pulled into the cassette" though that
is what I thought too.

Sure it can, and it happens with fair regularity on MTBs. It can be
a b-screw screw-up, limit screw screw-up, worn chain, cassette,
chainrings -- a stick, rock. It can even be caused by a shift and a
bump. I have never heard of the b-screw tab breaking, but maybe that
happens on Campy derailleurs -- and if so, that is a major design FU,
particularly considering the consequences.

Until I analyzed it. The stop on the rear derailleur with is a small
sheet steel washer-like mechanism that keeps the derailleur from
rotating past the stop. Without that stop the idler pulley was pulled
into the cassette and the entire mechanism was locked up solid.

FYI, your typical pully choices are "upper or lower" or "guide pulley"
(upper) or "tension pulley." (lower). I don't know what an idler
pulley is on a derailleur.

-- Jay Beattie.


And it's simple to avoid.
Finish any gear adjustment with this test:
http://www.yellowjersey.org/photosfr...t/gearchek.jpg

image from Canada, miketechinfo.com
I think Tom needs to hire a better mechanic. It seems like about a
quarter of his posts are about bike wrenching screw-ups.

And yet as a supposed mechanical engineer you don't even know how to hold an Allen wrench. I find it humorous that people who haven't seen a thing in their lives are so ready to tell others how to do things. Jay is telling us that since things happen on an MTB with a 42 tooth cassette they happen all the time on a Campy Record bike with a 28 tooth.

If it wasn't so comical you guys would be nothing more than pitiful.

Is there a 'wrong' way to hold an allen wrench? In two
tentacles rather than three? What?

Andrew, without actually seeing the problem or the initial setup people do not have the right to criticize other people's problems.
I'm not criticizing that specific problem. I'm criticizing your
mechanical aptitude in general. You've written an entire book here about
your mechanical mistakes, with an appendix covering your electronic
mistakes and your mis-ordered parts. You have retired the trophy for
bike wrenching incompetence.

As to holding Allen wrenches: I've built and rebuilt multiple bikes from
the frame up. I've disassembled and rebuilt multiple engines of cars,
plus motorcycles, lawn mowers and more. I'm a reasonably competent
machinist and a halfway competent welder. I've taught others how to do
those things.

I'm not claiming to be perfect. We all make mistakes. But someone who
makes as many mistakes as you should not be insulting others' mechanical
aptitude.

(And yes, we know, it's all Biden's fault. Please spare us the off-topic
political deflection nonsense.)

Tell me Frank, what were the mistakes I've written a book about. You are a person obviously on phycological medication and pretty much everyone is aware of this. What are you doing on a tech site when you've never yourself added anything to it beyond your cool lights that are never used because you sight is too bad to go out after dark?

On Tuesday, May 11, 2021 at 10:02:13 AM UTC-7, wrote:
On Tuesday, May 11, 2021 at 9:39:56 AM UTC-7, Frank Krygowski wrote:
On 5/11/2021 11:44 AM, Tom Kunich wrote:
On Tuesday, May 11, 2021 at 6:56:30 AM UTC-7, AMuzi wrote:
On 5/11/2021 8:41 AM, Tom Kunich wrote:
On Monday, May 10, 2021 at 7:09:57 PM UTC-7, Frank Krygowski wrote:
On 5/10/2021 9:42 PM, AMuzi wrote:
On 5/10/2021 8:22 PM, jbeattie wrote:
On Monday, May 10, 2021 at 4:51:13 PM UTC-7, wrote:
On Monday, May 10, 2021 at 4:19:53 PM UTC-7, jbeattie wrote:
On Monday, May 10, 2021 at 9:59:14 AM UTC-7, wrote:
I did a climbing ride sort of - it was less that 1000 feet and the
steepest part was only about 9%. For some reason I was dog tired
and it really hurt.

3/4ths of the way in to the ride and luckily downhill to most
extent, the rear derailleur idler pully exploded. I assumed that it
was the roller bearing idler pulley but working on it what happened
was the the sheet metal rotational limit piece on the derailleur
appears to have broken off which caused the pulley to be pulled
into the cassette which broke it and this entire thing locked up
the whole drive train which bent the drop out. So I have to get a
replacement for that. After removing the rear derailleur it will
not thread back in.

Finding a replacement ought to be a whole lot of fun.
It sounds like you pulled the guide pulley into the cassette and the
other damage followed and not vice versa. That can happen under
certain unfortunate circumstances.

The rear derailleur cannot be "pulled into the cassette" though that
is what I thought too.

Sure it can, and it happens with fair regularity on MTBs. It can be
a b-screw screw-up, limit screw screw-up, worn chain, cassette,
chainrings -- a stick, rock. It can even be caused by a shift and a
bump. I have never heard of the b-screw tab breaking, but maybe that
happens on Campy derailleurs -- and if so, that is a major design FU,
particularly considering the consequences.

Until I analyzed it. The stop on the rear derailleur with is a small
sheet steel washer-like mechanism that keeps the derailleur from
rotating past the stop. Without that stop the idler pulley was pulled
into the cassette and the entire mechanism was locked up solid.

FYI, your typical pully choices are "upper or lower" or "guide pulley"
(upper) or "tension pulley." (lower). I don't know what an idler
pulley is on a derailleur.

-- Jay Beattie.


And it's simple to avoid.
Finish any gear adjustment with this test:
http://www.yellowjersey.org/photosfr...t/gearchek.jpg

image from Canada, miketechinfo.com
I think Tom needs to hire a better mechanic. It seems like about a
quarter of his posts are about bike wrenching screw-ups.

And yet as a supposed mechanical engineer you don't even know how to hold an Allen wrench. I find it humorous that people who haven't seen a thing in their lives are so ready to tell others how to do things. Jay is telling us that since things happen on an MTB with a 42 tooth cassette they happen all the time on a Campy Record bike with a 28 tooth.

If it wasn't so comical you guys would be nothing more than pitiful..

Is there a 'wrong' way to hold an allen wrench? In two
tentacles rather than three? What?

Andrew, without actually seeing the problem or the initial setup people do not have the right to criticize other people's problems.
I'm not criticizing that specific problem. I'm criticizing your
mechanical aptitude in general. You've written an entire book here about
your mechanical mistakes, with an appendix covering your electronic
mistakes and your mis-ordered parts. You have retired the trophy for
bike wrenching incompetence.

As to holding Allen wrenches: I've built and rebuilt multiple bikes from
the frame up. I've disassembled and rebuilt multiple engines of cars,
plus motorcycles, lawn mowers and more. I'm a reasonably competent
machinist and a halfway competent welder. I've taught others how to do
those things.

I'm not claiming to be perfect. We all make mistakes. But someone who
makes as many mistakes as you should not be insulting others' mechanical
aptitude.

(And yes, we know, it's all Biden's fault. Please spare us the off-topic
political deflection nonsense.)
Tell me Frank, what were the mistakes I've written a book about. You are a person obviously on phycological medication and pretty much everyone is aware of this. What are you doing on a tech site when you've never yourself added anything to it beyond your cool lights that are never used because you sight is too bad to go out after dark?

Without getting into whether there was some installation error, what you identify as "causes" are classic "effects" -- blown-up pulley, broken B-tension screw tab, etc., etc. I think you have cause and effect backward on this one.

-- Jay Beattie.

On 5/11/2021 11:39 AM, Frank Krygowski wrote:
On 5/11/2021 11:44 AM, Tom Kunich wrote:
On Tuesday, May 11, 2021 at 6:56:30 AM UTC-7, AMuzi wrote:
On 5/11/2021 8:41 AM, Tom Kunich wrote:
On Monday, May 10, 2021 at 7:09:57 PM UTC-7, Frank
Krygowski wrote:
On 5/10/2021 9:42 PM, AMuzi wrote:
On 5/10/2021 8:22 PM, jbeattie wrote:
On Monday, May 10, 2021 at 4:51:13 PM UTC-7,
wrote:
On Monday, May 10, 2021 at 4:19:53 PM UTC-7,
jbeattie wrote:
On Monday, May 10, 2021 at 9:59:14 AM UTC-7,
wrote:
I did a climbing ride sort of - it was less that
1000 feet and the
steepest part was only about 9%. For some reason I
was dog tired
and it really hurt.

3/4ths of the way in to the ride and luckily
downhill to most
extent, the rear derailleur idler pully exploded.
I assumed that it
was the roller bearing idler pulley but working on
it what happened
was the the sheet metal rotational limit piece on
the derailleur
appears to have broken off which caused the pulley
to be pulled
into the cassette which broke it and this entire
thing locked up
the whole drive train which bent the drop out. So
I have to get a
replacement for that. After removing the rear
derailleur it will
not thread back in.

Finding a replacement ought to be a whole lot of fun.
It sounds like you pulled the guide pulley into the
cassette and the
other damage followed and not vice versa. That can
happen under
certain unfortunate circumstances.

The rear derailleur cannot be "pulled into the
cassette" though that
is what I thought too.

Sure it can, and it happens with fair regularity on
MTBs. It can be
a b-screw screw-up, limit screw screw-up, worn chain,
cassette,
chainrings -- a stick, rock. It can even be caused by
a shift and a
bump. I have never heard of the b-screw tab breaking,
but maybe that
happens on Campy derailleurs -- and if so, that is a
major design FU,
particularly considering the consequences.

Until I analyzed it. The stop on the rear derailleur
with is a small
sheet steel washer-like mechanism that keeps the
derailleur from
rotating past the stop. Without that stop the idler
pulley was pulled
into the cassette and the entire mechanism was locked
up solid.

FYI, your typical pully choices are "upper or lower"
or "guide pulley"
(upper) or "tension pulley." (lower). I don't know
what an idler
pulley is on a derailleur.

-- Jay Beattie.


And it's simple to avoid.
Finish any gear adjustment with this test:
http://www.yellowjersey.org/photosfr...t/gearchek.jpg


image from Canada, miketechinfo.com
I think Tom needs to hire a better mechanic. It seems
like about a
quarter of his posts are about bike wrenching screw-ups.

And yet as a supposed mechanical engineer you don't even
know how to hold an Allen wrench. I find it humorous
that people who haven't seen a thing in their lives are
so ready to tell others how to do things. Jay is telling
us that since things happen on an MTB with a 42 tooth
cassette they happen all the time on a Campy Record bike
with a 28 tooth.

If it wasn't so comical you guys would be nothing more
than pitiful.

Is there a 'wrong' way to hold an allen wrench? In two
tentacles rather than three? What?

Andrew, without actually seeing the problem or the initial
setup people do not have the right to criticize other
people's problems.

I'm not criticizing that specific problem. I'm criticizing
your mechanical aptitude in general. You've written an
entire book here about your mechanical mistakes, with an
appendix covering your electronic mistakes and your
mis-ordered parts. You have retired the trophy for bike
wrenching incompetence.

As to holding Allen wrenches: I've built and rebuilt
multiple bikes from the frame up. I've disassembled and
rebuilt multiple engines of cars, plus motorcycles, lawn
mowers and more. I'm a reasonably competent machinist and a
halfway competent welder. I've taught others how to do those
things.

I'm not claiming to be perfect. We all make mistakes. But
someone who makes as many mistakes as you should not be
insulting others' mechanical aptitude.

(And yes, we know, it's all Biden's fault. Please spare us
the off-topic political deflection nonsense.)


Obviously dancing around the question of how to correctly
hold an allen key. We're waiting!

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

On 5/11/2021 12:35 PM, jbeattie wrote:
On Tuesday, May 11, 2021 at 10:02:13 AM UTC-7, wrote:
On Tuesday, May 11, 2021 at 9:39:56 AM UTC-7, Frank Krygowski wrote:
On 5/11/2021 11:44 AM, Tom Kunich wrote:
On Tuesday, May 11, 2021 at 6:56:30 AM UTC-7, AMuzi wrote:
On 5/11/2021 8:41 AM, Tom Kunich wrote:
On Monday, May 10, 2021 at 7:09:57 PM UTC-7, Frank Krygowski wrote:
On 5/10/2021 9:42 PM, AMuzi wrote:
On 5/10/2021 8:22 PM, jbeattie wrote:
On Monday, May 10, 2021 at 4:51:13 PM UTC-7, wrote:
On Monday, May 10, 2021 at 4:19:53 PM UTC-7, jbeattie wrote:
On Monday, May 10, 2021 at 9:59:14 AM UTC-7, wrote:
I did a climbing ride sort of - it was less that 1000 feet and the
steepest part was only about 9%. For some reason I was dog tired
and it really hurt.

3/4ths of the way in to the ride and luckily downhill to most
extent, the rear derailleur idler pully exploded. I assumed that it
was the roller bearing idler pulley but working on it what happened
was the the sheet metal rotational limit piece on the derailleur
appears to have broken off which caused the pulley to be pulled
into the cassette which broke it and this entire thing locked up
the whole drive train which bent the drop out. So I have to get a
replacement for that. After removing the rear derailleur it will
not thread back in.

Finding a replacement ought to be a whole lot of fun.
It sounds like you pulled the guide pulley into the cassette and the
other damage followed and not vice versa. That can happen under
certain unfortunate circumstances.

The rear derailleur cannot be "pulled into the cassette" though that
is what I thought too.

Sure it can, and it happens with fair regularity on MTBs. It can be
a b-screw screw-up, limit screw screw-up, worn chain, cassette,
chainrings -- a stick, rock. It can even be caused by a shift and a
bump. I have never heard of the b-screw tab breaking, but maybe that
happens on Campy derailleurs -- and if so, that is a major design FU,
particularly considering the consequences.

Until I analyzed it. The stop on the rear derailleur with is a small
sheet steel washer-like mechanism that keeps the derailleur from
rotating past the stop. Without that stop the idler pulley was pulled
into the cassette and the entire mechanism was locked up solid.

FYI, your typical pully choices are "upper or lower" or "guide pulley"
(upper) or "tension pulley." (lower). I don't know what an idler
pulley is on a derailleur.

-- Jay Beattie.


And it's simple to avoid.
Finish any gear adjustment with this test:
http://www.yellowjersey.org/photosfr...t/gearchek.jpg

image from Canada, miketechinfo.com
I think Tom needs to hire a better mechanic. It seems like about a
quarter of his posts are about bike wrenching screw-ups.

And yet as a supposed mechanical engineer you don't even know how to hold an Allen wrench. I find it humorous that people who haven't seen a thing in their lives are so ready to tell others how to do things. Jay is telling us that since things happen on an MTB with a 42 tooth cassette they happen all the time on a Campy Record bike with a 28 tooth.

If it wasn't so comical you guys would be nothing more than pitiful.

Is there a 'wrong' way to hold an allen wrench? In two
tentacles rather than three? What?

Andrew, without actually seeing the problem or the initial setup people do not have the right to criticize other people's problems.
I'm not criticizing that specific problem. I'm criticizing your
mechanical aptitude in general. You've written an entire book here about
your mechanical mistakes, with an appendix covering your electronic
mistakes and your mis-ordered parts. You have retired the trophy for
bike wrenching incompetence.

As to holding Allen wrenches: I've built and rebuilt multiple bikes from
the frame up. I've disassembled and rebuilt multiple engines of cars,
plus motorcycles, lawn mowers and more. I'm a reasonably competent
machinist and a halfway competent welder. I've taught others how to do
those things.

I'm not claiming to be perfect. We all make mistakes. But someone who
makes as many mistakes as you should not be insulting others' mechanical
aptitude.

(And yes, we know, it's all Biden's fault. Please spare us the off-topic
political deflection nonsense.)
Tell me Frank, what were the mistakes I've written a book about. You are a person obviously on phycological medication and pretty much everyone is aware of this. What are you doing on a tech site when you've never yourself added anything to it beyond your cool lights that are never used because you sight is too bad to go out after dark?

Without getting into whether there was some installation error, what you identify as "causes" are classic "effects" -- blown-up pulley, broken B-tension screw tab, etc., etc. I think you have cause and effect backward on this one.

-- Jay Beattie.

+1

See also, "Your Honor, the bicycle fork sprung suddenly and
threw my client right into the bus!"

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

On Tuesday, May 11, 2021 at 10:35:57 AM UTC-7, jbeattie wrote:
On Tuesday, May 11, 2021 at 10:02:13 AM UTC-7, wrote:
On Tuesday, May 11, 2021 at 9:39:56 AM UTC-7, Frank Krygowski wrote:
On 5/11/2021 11:44 AM, Tom Kunich wrote:
On Tuesday, May 11, 2021 at 6:56:30 AM UTC-7, AMuzi wrote:
On 5/11/2021 8:41 AM, Tom Kunich wrote:
On Monday, May 10, 2021 at 7:09:57 PM UTC-7, Frank Krygowski wrote:
On 5/10/2021 9:42 PM, AMuzi wrote:
On 5/10/2021 8:22 PM, jbeattie wrote:
On Monday, May 10, 2021 at 4:51:13 PM UTC-7, wrote:
On Monday, May 10, 2021 at 4:19:53 PM UTC-7, jbeattie wrote:
On Monday, May 10, 2021 at 9:59:14 AM UTC-7, wrote:
I did a climbing ride sort of - it was less that 1000 feet and the
steepest part was only about 9%. For some reason I was dog tired
and it really hurt.

3/4ths of the way in to the ride and luckily downhill to most
extent, the rear derailleur idler pully exploded. I assumed that it
was the roller bearing idler pulley but working on it what happened
was the the sheet metal rotational limit piece on the derailleur
appears to have broken off which caused the pulley to be pulled
into the cassette which broke it and this entire thing locked up
the whole drive train which bent the drop out. So I have to get a
replacement for that. After removing the rear derailleur it will
not thread back in.

Finding a replacement ought to be a whole lot of fun.
It sounds like you pulled the guide pulley into the cassette and the
other damage followed and not vice versa. That can happen under
certain unfortunate circumstances.

The rear derailleur cannot be "pulled into the cassette" though that
is what I thought too.

Sure it can, and it happens with fair regularity on MTBs. It can be
a b-screw screw-up, limit screw screw-up, worn chain, cassette,
chainrings -- a stick, rock. It can even be caused by a shift and a
bump. I have never heard of the b-screw tab breaking, but maybe that
happens on Campy derailleurs -- and if so, that is a major design FU,
particularly considering the consequences.

Until I analyzed it. The stop on the rear derailleur with is a small
sheet steel washer-like mechanism that keeps the derailleur from
rotating past the stop. Without that stop the idler pulley was pulled
into the cassette and the entire mechanism was locked up solid..

FYI, your typical pully choices are "upper or lower" or "guide pulley"
(upper) or "tension pulley." (lower). I don't know what an idler
pulley is on a derailleur.

-- Jay Beattie.


And it's simple to avoid.
Finish any gear adjustment with this test:
http://www.yellowjersey.org/photosfr...t/gearchek.jpg

image from Canada, miketechinfo.com
I think Tom needs to hire a better mechanic. It seems like about a
quarter of his posts are about bike wrenching screw-ups.

And yet as a supposed mechanical engineer you don't even know how to hold an Allen wrench. I find it humorous that people who haven't seen a thing in their lives are so ready to tell others how to do things. Jay is telling us that since things happen on an MTB with a 42 tooth cassette they happen all the time on a Campy Record bike with a 28 tooth.

If it wasn't so comical you guys would be nothing more than pitiful.

Is there a 'wrong' way to hold an allen wrench? In two
tentacles rather than three? What?

Andrew, without actually seeing the problem or the initial setup people do not have the right to criticize other people's problems.
I'm not criticizing that specific problem. I'm criticizing your
mechanical aptitude in general. You've written an entire book here about
your mechanical mistakes, with an appendix covering your electronic
mistakes and your mis-ordered parts. You have retired the trophy for
bike wrenching incompetence.

As to holding Allen wrenches: I've built and rebuilt multiple bikes from
the frame up. I've disassembled and rebuilt multiple engines of cars,
plus motorcycles, lawn mowers and more. I'm a reasonably competent
machinist and a halfway competent welder. I've taught others how to do
those things.

I'm not claiming to be perfect. We all make mistakes. But someone who
makes as many mistakes as you should not be insulting others' mechanical
aptitude.

(And yes, we know, it's all Biden's fault. Please spare us the off-topic
political deflection nonsense.)
Tell me Frank, what were the mistakes I've written a book about. You are a person obviously on phycological medication and pretty much everyone is aware of this. What are you doing on a tech site when you've never yourself added anything to it beyond your cool lights that are never used because you sight is too bad to go out after dark?
Without getting into whether there was some installation error, what you identify as "causes" are classic "effects" -- blown-up pulley, broken B-tension screw tab, etc., etc. I think you have cause and effect backward on this one.

It wasn't a B tension screw. Why are you talking about things you don't understand? The part that broke is known as a RD-RE116 and is s completely different part than the B-tension screw. It didn't bend and it did loose - it failed from metal fatigue. This didn't occur in the 8 speed units because the ratios between gears was high enough that you didn't have to shift from high gear to low very often.

On Tuesday, May 11, 2021 at 10:48:13 AM UTC-7, AMuzi wrote:
On 5/11/2021 11:39 AM, Frank Krygowski wrote:
On 5/11/2021 11:44 AM, Tom Kunich wrote:
On Tuesday, May 11, 2021 at 6:56:30 AM UTC-7, AMuzi wrote:
On 5/11/2021 8:41 AM, Tom Kunich wrote:
On Monday, May 10, 2021 at 7:09:57 PM UTC-7, Frank
Krygowski wrote:
On 5/10/2021 9:42 PM, AMuzi wrote:
On 5/10/2021 8:22 PM, jbeattie wrote:
On Monday, May 10, 2021 at 4:51:13 PM UTC-7,
wrote:
On Monday, May 10, 2021 at 4:19:53 PM UTC-7,
jbeattie wrote:
On Monday, May 10, 2021 at 9:59:14 AM UTC-7,
wrote:
I did a climbing ride sort of - it was less that
1000 feet and the
steepest part was only about 9%. For some reason I
was dog tired
and it really hurt.

3/4ths of the way in to the ride and luckily
downhill to most
extent, the rear derailleur idler pully exploded.
I assumed that it
was the roller bearing idler pulley but working on
it what happened
was the the sheet metal rotational limit piece on
the derailleur
appears to have broken off which caused the pulley
to be pulled
into the cassette which broke it and this entire
thing locked up
the whole drive train which bent the drop out. So
I have to get a
replacement for that. After removing the rear
derailleur it will
not thread back in.

Finding a replacement ought to be a whole lot of fun.
It sounds like you pulled the guide pulley into the
cassette and the
other damage followed and not vice versa. That can
happen under
certain unfortunate circumstances.

The rear derailleur cannot be "pulled into the
cassette" though that
is what I thought too.

Sure it can, and it happens with fair regularity on
MTBs. It can be
a b-screw screw-up, limit screw screw-up, worn chain,
cassette,
chainrings -- a stick, rock. It can even be caused by
a shift and a
bump. I have never heard of the b-screw tab breaking,
but maybe that
happens on Campy derailleurs -- and if so, that is a
major design FU,
particularly considering the consequences.

Until I analyzed it. The stop on the rear derailleur
with is a small
sheet steel washer-like mechanism that keeps the
derailleur from
rotating past the stop. Without that stop the idler
pulley was pulled
into the cassette and the entire mechanism was locked
up solid.

FYI, your typical pully choices are "upper or lower"
or "guide pulley"
(upper) or "tension pulley." (lower). I don't know
what an idler
pulley is on a derailleur.

-- Jay Beattie.


And it's simple to avoid.
Finish any gear adjustment with this test:
http://www.yellowjersey.org/photosfr...t/gearchek.jpg


image from Canada, miketechinfo.com
I think Tom needs to hire a better mechanic. It seems
like about a
quarter of his posts are about bike wrenching screw-ups.

And yet as a supposed mechanical engineer you don't even
know how to hold an Allen wrench. I find it humorous
that people who haven't seen a thing in their lives are
so ready to tell others how to do things. Jay is telling
us that since things happen on an MTB with a 42 tooth
cassette they happen all the time on a Campy Record bike
with a 28 tooth.

If it wasn't so comical you guys would be nothing more
than pitiful.

Is there a 'wrong' way to hold an allen wrench? In two
tentacles rather than three? What?

Andrew, without actually seeing the problem or the initial
setup people do not have the right to criticize other
people's problems.

I'm not criticizing that specific problem. I'm criticizing
your mechanical aptitude in general. You've written an
entire book here about your mechanical mistakes, with an
appendix covering your electronic mistakes and your
mis-ordered parts. You have retired the trophy for bike
wrenching incompetence.

As to holding Allen wrenches: I've built and rebuilt
multiple bikes from the frame up. I've disassembled and
rebuilt multiple engines of cars, plus motorcycles, lawn
mowers and more. I'm a reasonably competent machinist and a
halfway competent welder. I've taught others how to do those
things.

I'm not claiming to be perfect. We all make mistakes. But
someone who makes as many mistakes as you should not be
insulting others' mechanical aptitude.

(And yes, we know, it's all Biden's fault. Please spare us
the off-topic political deflection nonsense.)

Obviously dancing around the question of how to correctly
hold an allen key. We're waiting!

What is there to dance around? Frank may be a mechanical engineer but that doesn't mean that he is ANY kind of a mechanic. They have made torque wrenches so that people like Frank do not overtighten Allen bolts in carbon fiber frames. What has Frank ever added to this group that wasn't purely criticism?

On Tuesday, May 11, 2021 at 11:03:59 AM UTC-7, wrote:
On Tuesday, May 11, 2021 at 10:35:57 AM UTC-7, jbeattie wrote:
On Tuesday, May 11, 2021 at 10:02:13 AM UTC-7, wrote:
On Tuesday, May 11, 2021 at 9:39:56 AM UTC-7, Frank Krygowski wrote:
On 5/11/2021 11:44 AM, Tom Kunich wrote:
On Tuesday, May 11, 2021 at 6:56:30 AM UTC-7, AMuzi wrote:
On 5/11/2021 8:41 AM, Tom Kunich wrote:
On Monday, May 10, 2021 at 7:09:57 PM UTC-7, Frank Krygowski wrote:
On 5/10/2021 9:42 PM, AMuzi wrote:
On 5/10/2021 8:22 PM, jbeattie wrote:
On Monday, May 10, 2021 at 4:51:13 PM UTC-7, wrote:
On Monday, May 10, 2021 at 4:19:53 PM UTC-7, jbeattie wrote:
On Monday, May 10, 2021 at 9:59:14 AM UTC-7, wrote:
I did a climbing ride sort of - it was less that 1000 feet and the
steepest part was only about 9%. For some reason I was dog tired
and it really hurt.

3/4ths of the way in to the ride and luckily downhill to most
extent, the rear derailleur idler pully exploded. I assumed that it
was the roller bearing idler pulley but working on it what happened
was the the sheet metal rotational limit piece on the derailleur
appears to have broken off which caused the pulley to be pulled
into the cassette which broke it and this entire thing locked up
the whole drive train which bent the drop out. So I have to get a
replacement for that. After removing the rear derailleur it will
not thread back in.

Finding a replacement ought to be a whole lot of fun.
It sounds like you pulled the guide pulley into the cassette and the
other damage followed and not vice versa. That can happen under
certain unfortunate circumstances.

The rear derailleur cannot be "pulled into the cassette" though that
is what I thought too.

Sure it can, and it happens with fair regularity on MTBs. It can be
a b-screw screw-up, limit screw screw-up, worn chain, cassette,
chainrings -- a stick, rock. It can even be caused by a shift and a
bump. I have never heard of the b-screw tab breaking, but maybe that
happens on Campy derailleurs -- and if so, that is a major design FU,
particularly considering the consequences.

Until I analyzed it. The stop on the rear derailleur with is a small
sheet steel washer-like mechanism that keeps the derailleur from
rotating past the stop. Without that stop the idler pulley was pulled
into the cassette and the entire mechanism was locked up solid.

FYI, your typical pully choices are "upper or lower" or "guide pulley"
(upper) or "tension pulley." (lower). I don't know what an idler
pulley is on a derailleur.

-- Jay Beattie.


And it's simple to avoid.
Finish any gear adjustment with this test:
http://www.yellowjersey.org/photosfr...t/gearchek.jpg

image from Canada, miketechinfo.com
I think Tom needs to hire a better mechanic. It seems like about a
quarter of his posts are about bike wrenching screw-ups.

And yet as a supposed mechanical engineer you don't even know how to hold an Allen wrench. I find it humorous that people who haven't seen a thing in their lives are so ready to tell others how to do things. Jay is telling us that since things happen on an MTB with a 42 tooth cassette they happen all the time on a Campy Record bike with a 28 tooth.

If it wasn't so comical you guys would be nothing more than pitiful.

Is there a 'wrong' way to hold an allen wrench? In two
tentacles rather than three? What?

Andrew, without actually seeing the problem or the initial setup people do not have the right to criticize other people's problems.
I'm not criticizing that specific problem. I'm criticizing your
mechanical aptitude in general. You've written an entire book here about
your mechanical mistakes, with an appendix covering your electronic
mistakes and your mis-ordered parts. You have retired the trophy for
bike wrenching incompetence.

As to holding Allen wrenches: I've built and rebuilt multiple bikes from
the frame up. I've disassembled and rebuilt multiple engines of cars,
plus motorcycles, lawn mowers and more. I'm a reasonably competent
machinist and a halfway competent welder. I've taught others how to do
those things.

I'm not claiming to be perfect. We all make mistakes. But someone who
makes as many mistakes as you should not be insulting others' mechanical
aptitude.

(And yes, we know, it's all Biden's fault. Please spare us the off-topic
political deflection nonsense.)
Tell me Frank, what were the mistakes I've written a book about. You are a person obviously on phycological medication and pretty much everyone is aware of this. What are you doing on a tech site when you've never yourself added anything to it beyond your cool lights that are never used because you sight is too bad to go out after dark?
Without getting into whether there was some installation error, what you identify as "causes" are classic "effects" -- blown-up pulley, broken B-tension screw tab, etc., etc. I think you have cause and effect backward on this one.
It wasn't a B tension screw. Why are you talking about things you don't understand? The part that broke is known as a RD-RE116 and is s completely different part than the B-tension screw. It didn't bend and it did loose - it failed from metal fatigue. This didn't occur in the 8 speed units because the ratios between gears was high enough that you didn't have to shift from high gear to low very often.

That's not a sheet metal piece like you described (in your usual vague and sketchy way), and the typical failure mode for similar b-tension plates is, again, the derailleur getting pulled into the cassettes. SRAM uses a somewhat similar plate with a screw, and those have been known to break if the derailleur body is under-tightened to the hanger or if it becomes loose during riding. I doubt these plates see much in the way of fatigue if properly installed because they are squeezed between the derailleur body and the dropout, but I'll leave the fatigue analysis to Frank.

-- Jay Beattie.

On 5/11/2021 11:39 AM, jbeattie wrote:
On Tuesday, May 11, 2021 at 11:03:59 AM UTC-7, wrote:
On Tuesday, May 11, 2021 at 10:35:57 AM UTC-7, jbeattie wrote:
On Tuesday, May 11, 2021 at 10:02:13 AM UTC-7, wrote:
On Tuesday, May 11, 2021 at 9:39:56 AM UTC-7, Frank Krygowski wrote:
On 5/11/2021 11:44 AM, Tom Kunich wrote:
On Tuesday, May 11, 2021 at 6:56:30 AM UTC-7, AMuzi wrote:
On 5/11/2021 8:41 AM, Tom Kunich wrote:
On Monday, May 10, 2021 at 7:09:57 PM UTC-7, Frank Krygowski wrote:
On 5/10/2021 9:42 PM, AMuzi wrote:
On 5/10/2021 8:22 PM, jbeattie wrote:
On Monday, May 10, 2021 at 4:51:13 PM UTC-7, wrote:
On Monday, May 10, 2021 at 4:19:53 PM UTC-7, jbeattie wrote:
On Monday, May 10, 2021 at 9:59:14 AM UTC-7, wrote:
I did a climbing ride sort of - it was less that 1000 feet and the
steepest part was only about 9%. For some reason I was dog tired
and it really hurt.

3/4ths of the way in to the ride and luckily downhill to most
extent, the rear derailleur idler pully exploded. I assumed that it
was the roller bearing idler pulley but working on it what happened
was the the sheet metal rotational limit piece on the derailleur
appears to have broken off which caused the pulley to be pulled
into the cassette which broke it and this entire thing locked up
the whole drive train which bent the drop out. So I have to get a
replacement for that. After removing the rear derailleur it will
not thread back in.

Finding a replacement ought to be a whole lot of fun.
It sounds like you pulled the guide pulley into the cassette and the
other damage followed and not vice versa. That can happen under
certain unfortunate circumstances.

The rear derailleur cannot be "pulled into the cassette" though that
is what I thought too.

Sure it can, and it happens with fair regularity on MTBs. It can be
a b-screw screw-up, limit screw screw-up, worn chain, cassette,
chainrings -- a stick, rock. It can even be caused by a shift and a
bump. I have never heard of the b-screw tab breaking, but maybe that
happens on Campy derailleurs -- and if so, that is a major design FU,
particularly considering the consequences.

Until I analyzed it. The stop on the rear derailleur with is a small
sheet steel washer-like mechanism that keeps the derailleur from
rotating past the stop. Without that stop the idler pulley was pulled
into the cassette and the entire mechanism was locked up solid.

FYI, your typical pully choices are "upper or lower" or "guide pulley"
(upper) or "tension pulley." (lower). I don't know what an idler
pulley is on a derailleur.

-- Jay Beattie.


And it's simple to avoid.
Finish any gear adjustment with this test:
http://www.yellowjersey.org/photosfr...t/gearchek.jpg

image from Canada, miketechinfo.com
I think Tom needs to hire a better mechanic. It seems like about a
quarter of his posts are about bike wrenching screw-ups.

And yet as a supposed mechanical engineer you don't even know how to hold an Allen wrench. I find it humorous that people who haven't seen a thing in their lives are so ready to tell others how to do things. Jay is telling us that since things happen on an MTB with a 42 tooth cassette they happen all the time on a Campy Record bike with a 28 tooth.

If it wasn't so comical you guys would be nothing more than pitiful.

Is there a 'wrong' way to hold an allen wrench? In two
tentacles rather than three? What?

Andrew, without actually seeing the problem or the initial setup people do not have the right to criticize other people's problems.
I'm not criticizing that specific problem. I'm criticizing your
mechanical aptitude in general. You've written an entire book here about
your mechanical mistakes, with an appendix covering your electronic
mistakes and your mis-ordered parts. You have retired the trophy for
bike wrenching incompetence.

As to holding Allen wrenches: I've built and rebuilt multiple bikes from
the frame up. I've disassembled and rebuilt multiple engines of cars,
plus motorcycles, lawn mowers and more. I'm a reasonably competent
machinist and a halfway competent welder. I've taught others how to do
those things.

I'm not claiming to be perfect. We all make mistakes. But someone who
makes as many mistakes as you should not be insulting others' mechanical
aptitude.

(And yes, we know, it's all Biden's fault. Please spare us the off-topic
political deflection nonsense.)
Tell me Frank, what were the mistakes I've written a book about. You are a person obviously on phycological medication and pretty much everyone is aware of this. What are you doing on a tech site when you've never yourself added anything to it beyond your cool lights that are never used because you sight is too bad to go out after dark?
Without getting into whether there was some installation error, what you identify as "causes" are classic "effects" -- blown-up pulley, broken B-tension screw tab, etc., etc. I think you have cause and effect backward on this one.
It wasn't a B tension screw. Why are you talking about things you don't understand? The part that broke is known as a RD-RE116 and is s completely different part than the B-tension screw. It didn't bend and it did loose - it failed from metal fatigue. This didn't occur in the 8 speed units because the ratios between gears was high enough that you didn't have to shift from high gear to low very often.

That's not a sheet metal piece like you described (in your usual vague and sketchy way), and the typical failure mode for similar b-tension plates is, again, the derailleur getting pulled into the cassettes. SRAM uses a somewhat similar plate with a screw, and those have been known to break if the derailleur body is under-tightened to the hanger or if it becomes loose during riding. I doubt these plates see much in the way of fatigue if properly installed because they are squeezed between the derailleur body and the dropout, but I'll leave the fatigue analysis to Frank.

-- Jay Beattie.

I'm confused about this "derailleur pulled into the cassette"
phenomenon. What is it? I've witnessed first hand the derailleur-
shifted-into-spokes maneuver (from 3 ft behind on a steep slow hill) -
impressive to watch. Is it similar?

Mark J.