Rear Derailleurs

Great Eastern wrote on 13/01/2007 14:39 +0100:

Quoted message said:

I currently have a rear derailleur on my bike which is screwed to the
frame, and then has the space for the rear axle just like the one
shown in the pic (although mine is a Shimano one):
http://ec3.images-amazon.com/images/P/B000BO80RK.01-A3NN9THRUBU1AW._AA280_SCLZZZZZZZ_.gif

Looking at new ones, as shown
(http://www.chainreactioncycles.com/Models.aspx?ModelID=11969) they
attach differently....I assume then this style has replaced the old
type its not possible to fit these new ones??

The one you have is the silver metal plate called a hanger and the
derailleur screwed into it. It looks like your's has a cover over the
allen bolt which screws the two together and you should be able to
remove that and unscrew it from the hanger and screw the new one in its
place. What you remove will look like the chain reaction link picture
and the allen bolt is that round hole on the top left. The hanger bit
on its own will look a bit like one of these:
http://www.chainreactioncycles.com/SearchResults.aspx?Search=hanger&x=0&y=0

--
Tony

"...has many omissions and contains much that is apocryphal, or at least
wildly inaccurate..."
Douglas Adams; The Hitchhiker's Guide to the Galaxy

In article <[email hidden]>, Great Eastern
[email hidden] says...

Quoted message said:

I currently have a rear derailleur on my bike which is screwed to the
frame, and then has the space for the rear axle just like the one shown
in the pic (although mine is a Shimano one):
http://ec3.images-amazon.com/images/P/B000BO80RK.01-A3NN9THRUBU1AW._AA280_SCLZZZZZZZ_.gif

Looking at new ones, as shown
(http://www.chainreactioncycles.com/Models.aspx?ModelID=11969) they
attach differently....I assume then this style has replaced the old type
its not possible to fit these new ones??

The ones with the integral bracket are el cheapo - both types have been
available for a long time. If the bracket on your mech isn't removable
you can get a separate one that will allow the fitting of a better mech
to your frame.

Rob Morley said:

In article <[email hidden]>, Great Eastern
[email hidden] says...

Quoted message said:

I currently have a rear derailleur on my bike which is screwed to the
frame, and then has the space for the rear axle just like the one
shown in the pic (although mine is a Shimano one):
http://ec3.images-amazon.com/images/P/B000BO80RK.01-A3NN9THRUBU1AW._AA280_SCLZZZZZZZ_.gif

Looking at new ones, as shown
(http://www.chainreactioncycles.com/Models.aspx?ModelID=11969) they
attach differently....I assume then this style has replaced the old
type its not possible to fit these new ones??

The ones with the integral bracket are el cheapo - both types have
been available for a long time. If the bracket on your mech isn't
removable you can get a separate one that will allow the fitting of a
better mech to your frame.

Or those with the bracket are ancient.

I have an 1980's one with a removable bracket (Shimano), supplied with the
bracket.
The usual (modern) fitting allen screw removes the mechanism from the
bracket.

Off topic link for the OP:
http://www.nigelcliffe.photobook.org.uk/c310576.html

--
Nigel Cliffe,
Webmaster at http://www.2mm.org.uk/

In article <[email hidden]>, Nigel Cliffe
[email hidden] says...

Quoted message said:

Rob Morley wrote:

Quoted message said:

Quoted message said:

The ones with the integral bracket are el cheapo - both types have
been available for a long time. If the bracket on your mech isn't
removable you can get a separate one that will allow the fitting of a
better mech to your frame.

Or those with the bracket are ancient.

I have an 1980's one with a removable bracket (Shimano), supplied with the
bracket.
The usual (modern) fitting allen screw removes the mechanism from the
bracket.

By 'integral' I meant fixed rather than removable.

Rob Morley said:

In article <[email hidden]>, Nigel Cliffe
[email hidden] says...

Quoted message said:

Rob Morley wrote:

Quoted message said:

Quoted message said:

The ones with the integral bracket are el cheapo - both types have
been available for a long time. If the bracket on your mech isn't
removable you can get a separate one that will allow the fitting of
a better mech to your frame.

Or those with the bracket are ancient.

I have an 1980's one with a removable bracket (Shimano), supplied
with the bracket.
The usual (modern) fitting allen screw removes the mechanism from the
bracket.

By 'integral' I meant fixed rather than removable.

OK, agree with your "el cheapo" description.

- Nigel

--
Nigel Cliffe,
Webmaster at http://www.2mm.org.uk/

in message <[email hidden]>, Great Eastern

(') said:

I currently have a rear derailleur on my bike which is screwed to the
frame, and then has the space for the rear axle just like the one shown
in the pic (although mine is a Shimano one):

http://ec3.images-amazon.com/images/P/B000BO80RK.01-A3NN9THRUBU1AW._AA280_SCLZZZZZZZ_.gif

Used to be common in the 1960s, now only on the very cheapest derailleurs.

Quoted message said:

Looking at new ones, as shown
(http://www.chainreactioncycles.com/Models.aspx?ModelID=11969)

Now almost universal.

Quoted message said:

they
attach differently....I assume then this style has replaced the old type
its not possible to fit these new ones??

It isn't as bad as that. What's changed is that the derailleur hanger (the
hooky bit at the top of the first picture) is now normally part of the
frame (or else is a special fitting to the frame). This helps to make the
alignment more precise. But the old style hook-on-the-axle hangers still
work, and if you unbolt the one from your old derailleur you will almost
certainly find that your new derailleur will bolt straight onto it.

--
[email hidden] (Simon Brooke) http://www.jasmine.org.uk/~simon/

;; Life would be much easier if I had the source code.

In case you can't unbolt the hanger from rest of mech, you can buy another
one separately:

www.sjscycles.co.uk/product-0-Shimano-rear-gear-hanger-bracket--fixing-bolt-420.htm

~PB

Simon Brooke said:

It isn't as bad as that. What's changed is that the derailleur hanger (the
hooky bit at the top of the first picture) is now normally part of the
frame (or else is a special fitting to the frame). This helps to make the
alignment more precise. But the old style hook-on-the-axle hangers still
work, and if you unbolt the one from your old derailleur you will almost
certainly find that your new derailleur will bolt straight onto it.

Thanks to everyone for the replies, I can see what you mean now
regarding the parts, however I doubt I'm going to find a replacement
which is suitable for a 6 speed!

Great Eastern said:

Thanks to everyone for the replies, I can see what you mean now
regarding the parts, however I doubt I'm going to find a replacement
which is suitable for a 6 speed!

I know that one shouldn't follow up on ones own posts but...

....I've just realised, it doesn't matter does it. an 8 or 9 speed
deraileur will work on 6 no fuss...its if I were trying to do the
opposite I'd have problems.

Great Eastern wrote on 13/01/2007 21:31 +0100:

Quoted message said:

Thanks to everyone for the replies, I can see what you mean now
regarding the parts, however I doubt I'm going to find a replacement
which is suitable for a 6 speed!

Any Shimano derailleur should be a suitable replacement - they are not
dependent on the number of speeds so as long as you stick with the same
brand you can't go far wrong. Some of the cheap end of the range (the
TY ones) even still come with the hanger included.

--
Tony

"...has many omissions and contains much that is apocryphal, or at least
wildly inaccurate..."
Douglas Adams; The Hitchhiker's Guide to the Galaxy

in message <[email hidden]>, Great

Eastern (') said:

Simon Brooke said:

It isn't as bad as that. What's changed is that the derailleur hanger
(the hooky bit at the top of the first picture) is now normally part of
the frame (or else is a special fitting to the frame). This helps to
make the alignment more precise. But the old style hook-on-the-axle
hangers still work, and if you unbolt the one from your old derailleur
you will almost certainly find that your new derailleur will bolt
straight onto it.

Thanks to everyone for the replies, I can see what you mean now
regarding the parts, however I doubt I'm going to find a replacement
which is suitable for a 6 speed!

Unless you're using an indexed lever, it doesn't matter how many 'speeds'
it says it is. The derailleur mechanism itself doesn't care. What matters
is that it can take up enough slack chain and has sufficient lateral
travel; provided it satisfies those criteria it will work. And seeing
modern systems have more lateral travel than older ones, all you have to
worry about is the chain capacity.

I'd advise not using one designed for nine or ten speed chains, as the cage
on those might be a bit narrow for a six speed chain.

--
[email hidden] (Simon Brooke) http://www.jasmine.org.uk/~simon/
Ring of great evil
Small one casts it into flame
Bringing rise of Men ;; gonzoron

Simon Brooke wrote on 13/01/2007 23:28 +0100:

Quoted message said:

I'd advise not using one designed for nine or ten speed chains, as the cage
on those might be a bit narrow for a six speed chain.

Sheldon suggests the opposite:

"Rear derailers often are referred to as "7-speed", "8-speed" or
"9-speed." This is not as important a distinction as it might appear.
Current model derailers are pretty much interchangeable within brands. A
"7-speed" or "8-speed" designation generally just indicates that the
derailer is an older design, or a cheaper model. They'll all work with
all 3 systems, though the models marked "9-speed" will generally be
slightly better (whatever cluster you use.)"
http://sheldonbrown.com/harris/derailers-rear.html

--
Tony

"...has many omissions and contains much that is apocryphal, or at least
wildly inaccurate..."
Douglas Adams; The Hitchhiker's Guide to the Galaxy

Simon Brooke said:

I'd advise not using one designed for nine or ten speed chains, as the cage
on those might be a bit narrow for a six speed chain.

I'm in the process of changing my freewheel for a non-broken one so have
a new chain ready anyway.

I'm also going to replace the Bottom Bracket as the current one
sometimes makes worrying noises so a better crankset will be used as well.

In article <[email hidden]>, Tony Raven
[email hidden] says...

Quoted message said:

Simon Brooke wrote on 13/01/2007 23:28 +0100:

Quoted message said:

I'd advise not using one designed for nine or ten speed chains, as the cage
on those might be a bit narrow for a six speed chain.

Sheldon suggests the opposite:

But Sheldon can't even spell derailleur. ;^>

Nigel Cliffe said:

I have an 1980's one with a removable bracket (Shimano), supplied with the
bracket.
The usual (modern) fitting allen screw removes the mechanism from the
bracket.

Probably El Cheapo was the case with this one, now replaced with a much
better version which had the hanger with it.

Quoted message said:

Off topic link for the OP:
http://www.nigelcliffe.photobook.org.uk/c310576.html

Ah very good. A railway museum near to me has a GER 4 wheel coach,
Number 19, which is supposedly very near to complete after some
restoration, will be interesting when its complete!