Occluded dropouts - Specialized circa 1989

James Thomson said:

I've seen a few dropouts of this style on late-eighties Specialized bikes -
Rockhoppers and Rock Combos:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=300070645886

Does anyone know what the idea was?

James Thomson

while I don't have an answer to your question. I do have one of these
frames. I once had a bike shop say I could turn it singlespeed by
removing that piece of metal in the dropout, I am wondering if that is
a good idea? I have had troubles in the past with the wheel slipping
forward on tough climbs and sprints. I try to keep the qick release
tight, but I don't ride the bike often. when I do it is just around
town. I have had several close calls in traffic when the wheel pulls
forward and slams me against the bars. any help there would be nice too.

dan

futrino said:

while I don't have an answer to your question. I do have one of these
frames. I once had a bike shop say I could turn it singlespeed by
removing that piece of metal in the dropout, I am wondering if that is
a good idea? I have had troubles in the past with the wheel slipping
forward on tough climbs and sprints. I try to keep the qick release
tight, but I don't ride the bike often. when I do it is just around
town. I have had several close calls in traffic when the wheel pulls
forward and slams me against the bars. any help there would be nice too.

A decent quick-release should prevent this from happening. What is
probably wrong is that either

1) It's not a decent quick release. Get a Shimano one as a replacement.
No titanium or aluminum here. You want strength.

2) Too much of your axle is sticking out on one side, and the quick
release bottoms out on the axle before it clamps securely on the frame.
This is a rather common problem, caused by either mis-centered axles or
very thin dropouts.

--

David L. Johnson

The motor car reflects our standard of living and gauges the
speed of our present life. It long ago ran down Simple Living,
and never halted to inquire about the prostrate figure which
fell as its victim. -- Warren G. Harding

James Thomson said:

I've seen a few dropouts of this style on late-eighties Specialized bikes -
Rockhoppers and Rock Combos:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=300070645886

Does anyone know what the idea was?

James Thomson

I would say they are offset, not occluded. The dropout slot is
completely open and not blocked by anything (as it would be if
occluded).

Perhaps it makes it easier to close QR's?

HTH

Quoted message said:

James Thomson said:

I've seen a few dropouts of this style on late-eighties Specialized
bikes -
Rockhoppers and Rock Combos:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=300070645886
Does anyone know what the idea was?

futrino said:

while I don't have an answer to your question. I do have one of these
frames. I once had a bike shop say I could turn it singlespeed by
removing that piece of metal in the dropout, I am wondering if that is
a good idea? I have had troubles in the past with the wheel slipping
forward on tough climbs and sprints. I try to keep the qick release
tight, but I don't ride the bike often. when I do it is just around
town. I have had several close calls in traffic when the wheel pulls
forward and slams me against the bars. any help there would be nice too.

Get a steel skewer if yours is aluminum and lube the cam inside the bell
- it won't slip. As a matter of fact it will print its outline on the
steel frame with moderate hand pressure.

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

"D'ohBoy" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

James Thomson said:

I've seen a few dropouts of this style on late-eighties Specialized
bikes -
Rockhoppers and Rock Combos:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=300070645886

Does anyone know what the idea was?

James Thomson

I would say they are offset, not occluded. The dropout slot is
completely open and not blocked by anything (as it would be if
occluded).

Perhaps it makes it easier to close QR's?

HTH

Sorry, don't know what they're for, but my 1970's PX10 has inserts in the
back of the dropouts, too. They are held in by bolts, so could be adjusted
fore and aft. Maybe to better center the rim between the chain stays? The
Specialized ones don't look adjustable, though.
Kerry

"D'ohBoy" <[email hidden]> a écrit:

Quoted message said:

I would say they are offset, not occluded. The dropout slot is
completely open and not blocked by anything (as it would be if
occluded).

Here's a better picture:

http://www.flickr.com/photos/jimg/251923576/in/set-72157594298401528/

http://tinyurl.com/2lk45s

James Thomson

James Thomson said:

I've seen a few dropouts of this style on late-eighties Specialized bikes -
Rockhoppers and Rock Combos:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=300070645886

Does anyone know what the idea was?

I've also had one like that without the hole, but where the
dropout slot was not machined all the way back. I think it was
on an old Rockhopper.

I assumed that the reason was to use the same forging for
many dropouts, but to set the chainstay length (and/or axle
position relative to the derailleur) on a given frame by
controlling how far back the slot was machined out.

Ben

James Thomson said:

Here's a better picture:

http://www.flickr.com/photos/jimg/251923576/in/set-72157594298401528/

http://tinyurl.com/2lk45s

Odd.
--
JT
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Remove "remove" to reply
Visit http://www.jt10000.com
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Quoted message said:

"D'ohBoy" <[email hidden]> a écrit:

Quoted message said:

I would say they are offset, not occluded. The dropout slot is
completely open and not blocked by anything (as it would be if
occluded).

James Thomson said:

Here's a better picture:
http://www.flickr.com/photos/jimg/251923576/in/set-72157594298401528/
http://tinyurl.com/2lk45s

Oh, that's what you meant!
I believe that was done mid-80s to conform to Shimano's SIS
requirements. It's only a small change of the part and still allows use
of the already-in-place frame fixtures. Just my WAG.

Here is that spec:
http://www.yellowjersey.org/sisend.html

As the PX-10 rider's commented, the preferred axle placement for optimal
gear performance could be overridden. On the French bikes with a
wrench, on Campagnolo ends with fingertips or here with 2 quick cuts.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971

James Thomson said:

"D'ohBoy" <[email hidden]> a écrit:

Quoted message said:

I would say they are offset, not occluded. The dropout slot is
completely open and not blocked by anything (as it would be if
occluded).

Here's a better picture:

http://www.flickr.com/photos/jimg/251923576/in/set-72157594298401528/

http://tinyurl.com/2lk45s

James Thomson

D'oh. Yah, occluded is right. D'ohBoy lives up to his moniker.

Thanks for the clarifying pic.

D'ohBoy

A Muzi said:

Quoted message said:

James Thomson said:

I've seen a few dropouts of this style on late-eighties Specialized
bikes -
Rockhoppers and Rock Combos:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=300070645886
Does anyone know what the idea was?

futrino said:

while I don't have an answer to your question. I do have one of these
frames. I once had a bike shop say I could turn it singlespeed by
removing that piece of metal in the dropout, I am wondering if that is
a good idea? I have had troubles in the past with the wheel slipping
forward on tough climbs and sprints. I try to keep the qick release
tight, but I don't ride the bike often. when I do it is just around
town. I have had several close calls in traffic when the wheel pulls
forward and slams me against the bars. any help there would be nice too.

Get a steel skewer if yours is aluminum and lube the cam inside the bell
- it won't slip. As a matter of fact it will print its outline on the
steel frame with moderate hand pressure.

By the way, is it possible to cause damage by doing up a QR too tight? With
Horizontal dropouts I tend to do them up very tight, but am always worried
I'm going to break something.

(these are steel Campag QRs)

Jim Higson said:

By the way, is it possible to cause damage by doing up a QR too tight? With
Horizontal dropouts I tend to do them up very tight, but am always worried
I'm going to break something.

(these are steel Campag QRs)

ofcourse apart from too much bearing preload:
www.m-gineering.nl/oopsg.htm (~1/3 rd down)
--
---
Marten Gerritsen

INFOapestaartjeM-GINEERINGpuntNL
www.m-gineering.nl

Jim Higson said:

By the way, is it possible to cause damage by doing up a QR too tight?

No, assuming the wheel bearings are adjusted properly (not too tight).

--
JT
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Visit http://www.jt10000.com
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James Thomson said:

I've seen a few dropouts of this style on late-eighties Specialized bikes -
Rockhoppers and Rock Combos:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=300070645886

Does anyone know what the idea was?

James Thomson

I also have a frame with one of these; it's an old japanese one of
confusing quality levels; the tubing is Tange No. 1, but the head tube
is one of those "faked-lug" things, where (either the centre or the
end) sections have been formed from the same tube. The droputs are
similar in profile as those shown in the ebay item - but the outside
flat where the qr clamps is also formed by stamping from the inside
face - the thickness of the dropout is unchanged, although it looks
from the outside like a forged dropout.

I would be surprised to see exactly the same dropout on a "quality"
cycle frame, such as one might expect from the names dropped above;
more likely that which I have is a copy of a rare variant of better
quality.

The frame is, however, quite light - or was until I brazed some
disc-brake mountings to it (this was in the 1970's so the mounting
plates were rather heavier than what is available nowadays); and it
has not shown any structural problems despite semi-regular use and one
collision with a motorcar which totaled the rear wheel.

M-gineering said:

Jim Higson said:

By the way, is it possible to cause damage by doing up a QR too tight?
With Horizontal dropouts I tend to do them up very tight, but am always
worried I'm going to break something.

(these are steel Campag QRs)

ofcourse apart from too much bearing preload:
www.m-gineering.nl/oopsg.htm (~1/3 rd down)

These pages always give me nightmares!

On Jan 24, 4:35 am, Jim Higson <[email hidden]> wrote:

By the way, is it possible to cause damage by doing up a QR too tight?
With

Quoted message said:

Horizontal dropouts I tend to do them up very tight, but am always worried
I'm going to break something.

Quoted message said:

(these are steel Campag QRs)

I've seen two people break Campy steel skewer rods by overtightening.
Sounds kind of like a spoke breaking, only bigger and thicker. Imagine
that! What was interesting was the delay between tightening and
breaking. Both took several seconds. Since the first one <g>, I've
tightened mine (pushed the skewer closed) with a medium kind of force,
wondering if there was a over-tightness that might lead to more delay
in the breaking process. Like, say, a delay that would give you enough
time to get on the bike and get started on that first big downhill near
the house.

Skewers don't need to be crushing tight on a fixed rear wheel, either.
The dropout faces should be "clean" and parallel, which is a quick job
with a shop dropout tool. (Probably the usual cause): If the hub axle
is a little too long, and protrudes past the outside face of the
dropout, the axle end will stop the skewer head from clamping onto the
dropout, and the wheel will slip no matter how tight the skewer is.
--D-y

Quoted message said:

Quoted message said:

Quoted message said:

James Thomson wrote:
> I've seen a few dropouts of this style on late-eighties Specialized
> bikes -
> Rockhoppers and Rock Combos:
> http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=300070645886
> Does anyone know what the idea was?

Quoted message said:

Quoted message said:

futrino said:

while I don't have an answer to your question. I do have one of these
frames. I once had a bike shop say I could turn it singlespeed by
removing that piece of metal in the dropout, I am wondering if that is
a good idea? I have had troubles in the past with the wheel slipping
forward on tough climbs and sprints. I try to keep the qick release
tight, but I don't ride the bike often. when I do it is just around
town. I have had several close calls in traffic when the wheel pulls
forward and slams me against the bars. any help there would be nice too.

Quoted message said:

A Muzi said:

Get a steel skewer if yours is aluminum and lube the cam inside the bell
- it won't slip. As a matter of fact it will print its outline on the
steel frame with moderate hand pressure.

Jim Higson said:

By the way, is it possible to cause damage by doing up a QR too tight? With
Horizontal dropouts I tend to do them up very tight, but am always worried
I'm going to break something.
(these are steel Campag QRs)

I have seen Campagnolo skewers with a broken bell cover, but rarely.

Lube the cam and use a moderate pressure. Press with your palm while
grasping spokes with your fingers. It needn't be painful. Raleigh's
manual says you should see the outline of the lever on your palm for a
few seconds (no haematoma!) which seems about right.

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