shimano 105 front derailleur limit screws

On Mon, 31 Oct 2005 12:19:53 -0500, "Phil, Squid-in-Training"
wrote:

Robin Hubert wrote:

It's so easy to see. Just move the derailleur in either direction by
hand and look to see which screw contacts the stop!

A lot of them have hidden assemblies.

A lot? I've never even seen one with a hidden assembly. Can you name
one?

JT

****************************
Remove "remove" to reply
Visit http://www.jt10000.com
****************************

Robin Hubert wrote:
Care to name one in which you can't see the screws contact the arms?
In my limited experience I haven't seen one.

Yes. Consider yourself enlightened. Shimano old-school 105 braze-on,
Shimano XT top-swing, top pull, Shimano Alivio bottom-swing, top pull, all
on bikes in my own household.

http://plaza.ufl.edu/phillee/ebay/cdale1.jpg
http://plaza.ufl.edu/phillee/ebay/cdale2.jpg

(sorry for the following bad photos)
http://plaza.ufl.edu/phillee/ebay/k21.jpg
http://plaza.ufl.edu/phillee/ebay/k22.jpg
http://plaza.ufl.edu/phillee/ebay/k23.jpg

http://plaza.ufl.edu/phillee/ebay/stp1.jpg
http://plaza.ufl.edu/phillee/ebay/stp2.jpg

Clearly the 105 braze-on is fully enclosed, with absolutely no way of
viewing the screws, even from below. The XT is enclosed almost completely.
The Alivio is visible from below, but hardly a position one to want to
involve himself in for derailleur screw visibility.

--
Phil, Squid-in-Training

John Forrest Tomlinson wrote:
On Mon, 31 Oct 2005 12:19:53 -0500, "Phil, Squid-in-Training"
wrote:

Robin Hubert wrote:

It's so easy to see. Just move the derailleur in either direction
by hand and look to see which screw contacts the stop!

A lot of them have hidden assemblies.

A lot? I've never even seen one with a hidden assembly. Can you name
one?

Yes. Consider yourself enlightened. Shimano old-school 105 braze-on,
Shimano XT top-swing, top pull, Shimano Alivio bottom-swing, top pull, all
on bikes in my own household.

http://plaza.ufl.edu/phillee/ebay/cdale1.jpg
http://plaza.ufl.edu/phillee/ebay/cdale2.jpg

(sorry for the following bad photos)
http://plaza.ufl.edu/phillee/ebay/k21.jpg
http://plaza.ufl.edu/phillee/ebay/k22.jpg
http://plaza.ufl.edu/phillee/ebay/k23.jpg

http://plaza.ufl.edu/phillee/ebay/stp1.jpg
http://plaza.ufl.edu/phillee/ebay/stp2.jpg

Clearly the 105 braze-on is fully enclosed, with absolutely no way of
viewing the screws, even from below. The XT is enclosed almost completely.
The Alivio is visible from below, but hardly a position one to want to
involve himself in for derailleur screw visibility.

--
Phil, Squid-in-Training

http://plaza.ufl.edu/phillee/ebay/stp1.jpg
http://plaza.ufl.edu/phillee/ebay/stp2.jpg

http://plaza.ufl.edu/phillee/ebay/stp3.jpg

I forgot this one, showing the Alivio's bit of visibility from the other
side of the bike.
--
Phil, Squid-in-Training

http://plaza.ufl.edu/phillee/ebay/stp1.jpg
http://plaza.ufl.edu/phillee/ebay/stp2.jpg


http://plaza.ufl.edu/phillee/ebay/stp3.jpg

I forgot this one, showing the Alivio's bit of visibility from the other
side of the bike.
--
Phil, Squid-in-Training

"Phil, Squid-in-Training" wrote:
John Forrest Tomlinson wrote:
On Mon, 31 Oct 2005 12:19:53 -0500, "Phil, Squid-in-Training"
wrote:

Robin Hubert wrote:

It's so easy to see. Just move the derailleur in either direction
by hand and look to see which screw contacts the stop!

A lot of them have hidden assemblies.

A lot? I've never even seen one with a hidden assembly. Can you name
one?

Yes. Consider yourself enlightened. Shimano old-school 105 braze-on,
Shimano XT top-swing, top pull, Shimano Alivio bottom-swing, top pull, all
on bikes in my own household.

http://plaza.ufl.edu/phillee/ebay/cdale1.jpg
http://plaza.ufl.edu/phillee/ebay/cdale2.jpg

(sorry for the following bad photos)
http://plaza.ufl.edu/phillee/ebay/k21.jpg
http://plaza.ufl.edu/phillee/ebay/k22.jpg
http://plaza.ufl.edu/phillee/ebay/k23.jpg

http://plaza.ufl.edu/phillee/ebay/stp1.jpg
http://plaza.ufl.edu/phillee/ebay/stp2.jpg

Clearly the 105 braze-on is fully enclosed, with absolutely no way of
viewing the screws, even from below. The XT is enclosed almost
completely. The Alivio is visible from below, but hardly a position one to
want to involve himself in for derailleur screw visibility.

--
Phil, Squid-in-Training

If you understand how the stops work, it is easy enough to visualize which
screw is which in the "hidden assembly" by looking at the position of the
stops in relation to the pivot. It's not really hidden if the two screws
are on opposite sides of the relevant pivot. An example of something not on
opposite sides of a pivot would the rear derailleur stops that are located
on the back of derailleurs - but those aren't hidden because you can peek
inside the parallelogram.

Let's see, for the old school 105, the top screw is for the high limit. If
you visualize the derailleur moving towards the big ring, the thread end of
top screw will be moving forward towards a (hidden) stop, and the thread end
of lower screw will be moving backwards away from a hidden stop.

For the top pull XT, the back link will move outwards with the derailleur,
so it will be free to move outwards until it contacts the screw that is
further away from the frame (the outer one). The outer screw must be the
high limit.

On the Alivio, you have some scissoring action going on between the
horizontal link that is part of the cage and contains the limit screws and
the vertical link. As the cage move outwards, the thread end of the inner
screw will be moving towards the vertical link where the stop must be
located, so that must be the high limit screw.

By the way, I think you have your Shimano "swing" terminology backwards.
The 105 and XT in your photos are "down swing", the cage is below the fixed
part of the derailleur. The Alivio is "top swing" because the part that
moves is above the fixed part.

Phil, Squid-in-Training wrote:
Robin Hubert wrote:

Care to name one in which you can't see the screws contact the arms?
In my limited experience I haven't seen one.


Yes. Consider yourself enlightened. Shimano old-school 105 braze-on,
Shimano XT top-swing, top pull, Shimano Alivio bottom-swing, top pull, all
on bikes in my own household.

http://plaza.ufl.edu/phillee/ebay/cdale1.jpg
http://plaza.ufl.edu/phillee/ebay/cdale2.jpg

(sorry for the following bad photos)
http://plaza.ufl.edu/phillee/ebay/k21.jpg
http://plaza.ufl.edu/phillee/ebay/k22.jpg
http://plaza.ufl.edu/phillee/ebay/k23.jpg

http://plaza.ufl.edu/phillee/ebay/stp1.jpg
http://plaza.ufl.edu/phillee/ebay/stp2.jpg

Clearly the 105 braze-on is fully enclosed, with absolutely no way of
viewing the screws, even from below. The XT is enclosed almost completely.
The Alivio is visible from below, but hardly a position one to want to
involve himself in for derailleur screw visibility.


It seems to me, from those photos, you can still see, from the
*backside*, where the screws exit and contact the stops on the arms.

Robin Hubert

By the way, I think you have your Shimano "swing" terminology
backwards. The 105 and XT in your photos are "down swing", the cage
is below the fixed part of the derailleur. The Alivio is "top swing"
because the part that moves is above the fixed part.

Yes, I did; thanks.
--
Phil, Squid-in-Training

Robin Hubert wrote:
Phil, Squid-in-Training wrote:
Robin Hubert wrote:

Care to name one in which you can't see the screws contact the arms?
In my limited experience I haven't seen one.


Yes. Consider yourself enlightened. Shimano old-school 105
braze-on, Shimano XT top-swing, top pull, Shimano Alivio
bottom-swing, top pull, all on bikes in my own household.

http://plaza.ufl.edu/phillee/ebay/cdale1.jpg
http://plaza.ufl.edu/phillee/ebay/cdale2.jpg

(sorry for the following bad photos)
http://plaza.ufl.edu/phillee/ebay/k21.jpg
http://plaza.ufl.edu/phillee/ebay/k22.jpg
http://plaza.ufl.edu/phillee/ebay/k23.jpg

http://plaza.ufl.edu/phillee/ebay/stp1.jpg
http://plaza.ufl.edu/phillee/ebay/stp2.jpg

Clearly the 105 braze-on is fully enclosed, with absolutely no way of
viewing the screws, even from below. The XT is enclosed almost
completely. The Alivio is visible from below, but hardly a position
one to want to involve himself in for derailleur screw visibility.


It seems to me, from those photos, you can still see, from the
*backside*, where the screws exit and contact the stops on the arms.

Then you are mistaken. The 105 doesn't *have* any visible stops. Look back
at the cdale2.jpg picture. The assembly is internal to the top arm.

The XT has everything enclosed in aluminum. Look at k23.jpg again. One of
the stops is visible. It's the black aluminum bit covered in brown dust
with a notch cut out of the silver aluminum portion for it. The screw
itself is not visible, and to get in an angle to take that picture required
some acrobatics.

The Alivio, as I said before, is more visible than the others, but it isn't
nearly as visible as the 105 on my TT/road bike:

http://plaza.ufl.edu/phillee/ebay/tcr1.jpg
http://plaza.ufl.edu/phillee/ebay/tcr2.jpg

Do you see the difference?

--
Phil, Squid-in-Training