skewers

in the interest of getting my bike riding right, I picked up a new
Shimano rear skewer off fleaBay (it was just as cheap as buying a new
generic one at LBS) this one happened to be Dura-Ace. DA = good, right?
well the nut end has steel serrations but the cam end appears to be
aluminum.

We'll see if this does the do. I guess if you follow the lever on the
left rule you still end up with the steel serrations on the nut end on
the drive side, which is where the chain tries to pull the wheel
forward. Now I'm going to have to look at all my Shimano skewers. (not
that it matters in the grand scheme of things - I only have one bike
with horizontal dropouts. Do the VO or other "good guy" skewers have
steel serrations on both ends? What about Ultegra or "lower level"
Shimano? The aluminum capped nut does look sexier than plastic though.
Might have to pick up a DA one for the front, if just for the nut
(shiny stuff makes me happy. metal parts make me happy. this is Not News.)

I did go for a short ride this PM but for some reason traffic sucked in
an epic manner coming home from work today, a 20-some mile mostly
highway commute ended up taking and hour and 45 minutes. I literally
could have rode home and arrived home only a few minutes later. (good
argument for getting bike in top shape? But it wouldn't have mattered
today as I had to visit a job site before going to the office so I would
have driven anyway) So of course it was dark by the time I got on the
bike so all roadside adjustments were done by flashlight and were
therefore less than precise, and in the interest of getting some miles
in before it got too late I didn't bother to swap skewers today...

nate

--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

"Nate Nagel" wrote: (clip) I guess if you follow the lever on the
left rule you still end up with the steel serrations on the nut end on the
drive side, which is where the chain tries to pull the wheel forward.
(clip)
^^^^^^^^^^^^^^^^^^^
When you tighten the skewer. the same tension is applied along the entire
length, and the clamping force is the same at both ends. Reversing the
skewer won't make any difference.

Leo Lichtman wrote:
"Nate Nagel" wrote: (clip) I guess if you follow the lever on the
left rule you still end up with the steel serrations on the nut end on the
drive side, which is where the chain tries to pull the wheel forward.
(clip)
^^^^^^^^^^^^^^^^^^^
When you tighten the skewer. the same tension is applied along the entire
length, and the clamping force is the same at both ends. Reversing the
skewer won't make any difference.


Clamping force would be the same but wouldn't the effective coefficient
of friction be higher steel/steel than aluminum/steel? or do I not have
my head right?

nate


--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

"Nate Nagel" wrote in message
...
in the interest of getting my bike riding right, I picked up a new Shimano
rear skewer off fleaBay (it was just as cheap as buying a new generic one
at LBS) this one happened to be Dura-Ace. DA = good, right? well the nut
end has steel serrations but the cam end appears to be aluminum.

We'll see if this does the do. I guess if you follow the lever on the
left rule you still end up with the steel serrations on the nut end on the
drive side, which is where the chain tries to pull the wheel forward. Now
I'm going to have to look at all my Shimano skewers. (not that it matters
in the grand scheme of things - I only have one bike with horizontal
dropouts. Do the VO or other "good guy" skewers have steel serrations on
both ends? What about Ultegra or "lower level" Shimano? The aluminum
capped nut does look sexier than plastic though. Might have to pick up a
DA one for the front, if just for the nut (shiny stuff makes me happy.
metal parts make me happy. this is Not News.)

I did go for a short ride this PM but for some reason traffic sucked in an
epic manner coming home from work today, a 20-some mile mostly highway
commute ended up taking and hour and 45 minutes. I literally could have
rode home and arrived home only a few minutes later. (good argument for
getting bike in top shape? But it wouldn't have mattered today as I had
to visit a job site before going to the office so I would have driven
anyway) So of course it was dark by the time I got on the bike so all
roadside adjustments were done by flashlight and were therefore less than
precise, and in the interest of getting some miles in before it got too
late I didn't bother to swap skewers today...

nate

--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

nate,
My Ultegra skewer appears to be the same as your Dura Ace = magnetic nut,
non-magnetic cam end. A little hard to be certain on the cam end due to the
other steel pieces in the area.
Kerry

Leo Lichtman wrote:
"Nate Nagel" wrote: (clip) I guess if you follow the lever on the
left rule you still end up with the steel serrations on the nut end on the
drive side, which is where the chain tries to pull the wheel forward.
(clip)
^^^^^^^^^^^^^^^^^^^
When you tighten the skewer. the same tension is applied along the entire
length, and the clamping force is the same at both ends. Reversing the
skewer won't make any difference.



When you pull a wheel, does the axle move forward equally on both sides?

Group: rec.bicycles.tech
Date: Wed, Oct 7, 2009, 10:06pm (EDT-1) From: (z)

When you pull a wheel, does the axle
move forward equally on both sides?

No (trust me, I busted a whole bunch of axles on my cheap MTB-commuter
from this very thing).

The chain pulls against the cogs, overriding the clamping force on that
side, which gets yanked forward. And since there's nothing pulling on
the opposite side the nut/skewer holds that end of the axle in place.

Axle twists, sometimes resulting in breakage.

- -
Compliments of:
"Your Friendly Neighborhood Wheelman"

If you want to E-mail me use:
ChrisZCorner "at" webtv "dot" net

My website (final month):
http://geocities.com/czcorner

On Oct 8, 1:39*am, Nate Nagel wrote:

We'll see if this does the do. *I guess if you follow the lever on the
left rule you still end up with the steel serrations on the nut end on
the drive side, which is where the chain tries to pull the wheel
forward. *Now I'm going to have to look at all my Shimano skewers. *(not
that it matters in the grand scheme of things - I only have one bike
with horizontal dropouts. *Do the VO or other "good guy" skewers have
steel serrations on both ends? *What about Ultegra or "lower level"
Shimano? *The aluminum capped nut does look sexier than plastic though.
* Might have to pick up a DA one for the front, if just for the nut
(shiny stuff makes me happy. *metal parts make me happy. *this is Not News.)

Its a clamp. If any serations are needed they would be needed on the
axle ends pushing directly against the frame. The serations under the
head of the nut are worthless, or worse, with a QR skewer. There is a
clearance between the skewer and the bore of the axle, hypothetically
if the axle end slips, then the skewer can only retain the axle after
the clearance has been taken up. Using serations under the QRnut
means the frame end will become scarred unless the end is hard
plated. If the frame ends do not become scarred, then you are likely
not using enough clamping force. Metal creep due to the serated
interface slowly sinking into the frame will reduce skewer tension and
so the clamping force may become insufficient to retain the axle
location under high loads. Retensioning during an initial ride or the
next day will take up any creep which may occur.

When the clamping force is sufficient you will not budge the axle when
riding a steep hill. This is a good indicator, for it means that the
axle ends are remaining intimate with the frame ends and so you know
the axle is not flexing to any worrisome extent. This indication is
not possible if you use vertical dropouts and may lead to unecessary
strain upon the axle.

What tends to be the source of slipping axles is not the axle or QR
but the chromed frame ends. Having the outside with chrome plate on
is fine, but it is best if the inside remains as bare (painted) carbon
steel for this provides a greater friction interface than chrome plate
(or stainless ends). If you have chromed or stainless frame ends then
you will need a higher clamping force to prevent axle slippage. This
necessary higher clamping force is easier to obtain with a nutted
axle. So if you have chromed slotted ends and 'need' to use QR axles,
remove the plating on the inside face (which contacts the axle
locknut) of the dropout.

On Oct 8, 2:24*am, Jobst Brandt wrote:
Nate Nagel wrote:
in the interest of getting my bike riding right, I picked up a new
Shimano rear skewer off fleaBay (it was just as cheap as buying a
new generic one at LBS) this one happened to be Dura-Ace. *DA =
good, right? *well the nut end has steel serrations but the cam end
appears to be aluminum.
We'll see if this does the do. *I guess if you follow the lever on
the left rule you still end up with the steel serrations on the nut
end on the drive side, which is where the chain tries to pull the
wheel forward.

That's why6 we use vertical dropouts! *Bending the axle fore and aft
by chain tension causes dropout and axle failures, something I put up
with for many years.

You should have tried a normal nutted axle. Fashion for QR with
chromed ends got you, did it?

Don't rely on knurled surfaces to retain wheel
alignment! *I haven't done it in years and you must have seen where I
ride and I am using Shimano 7-speed rear hubs and QR's.

Been up any sleet driven mountains lately?

Now I'm going to have to look at all my Shimano skewers. *(not that
it matters in the grand scheme of things - I only have one bike with
horizontal dropouts. *Do the VO or other "good guy" skewers have
steel serrations on both ends? *What about Ultegra or "lower level"
Shimano? *The aluminum capped nut does look sexier than plastic
though. *Might have to pick up a DA one for the front, if just for
the nut (shiny stuff makes me happy. *metal parts make me happy.
this is Not News.)

Look moreover at your dropouts!

Go on, give us a clue. They must be designed wrong eh? ;-)

I did go for a short ride this PM but for some reason traffic sucked
in an epic manner coming home from work today, a 20-some mile mostly
highway commute ended up taking and hour and 45 minutes. *I
literally could have ridden home and arrived home only a few minutes
later. *(good argument for getting bike in top shape? *But it
wouldn't have mattered today as I had to visit a job site before
going to the office so I would have driven anyway) So of course it
was dark by the time I got on the bike so all roadside adjustments
were done by flashlight and were therefore less than precise, and in
the interest of getting some miles in before it got too late I
didn't bother to swap skewers today...

As I said, it's not the skewer but rather the dropout that allows the
wheel to come askew or not. *Get rid of the horizontal slotted
dropouts and note that bending fore and aft is easy because the
horizontal slot has no support fore and aft. *Just look at the gouges
wear marks on horizontal dropouts.

Er, uneccessary serations under the ends of the QR unit do contribute
to dropping clamping forces and so do contribute to axle movement
whether that be rocking or slippage. A rocking axle will still occur
with vertical dropouts if the clamping force is insufficient. Very
little marking should occur on the outside of the dropout for the
under head form of the QR unit should be smooth. Marking of the inner
faces of the dropouts does occur to an extent depending upon the form
of the axle locknuts. With shaping to the locknut it must deform the
dropout when sufficient clamping force is reached. It is adequate
clamping force which produces the marks. If you clamp up and dont
produce marking on the inner faces of the dropouts then you are more
likely to suffer axle damage.

On Oct 8, 3:00*am, Nate Nagel wrote:
Leo Lichtman wrote:
"Nate Nagel" wrote: *(clip) *I guess if you follow the lever on the
left rule you still end up with the steel serrations on the nut end on the
drive side, which is where the chain tries to pull the wheel forward.
(clip)
^^^^^^^^^^^^^^^^^^^
When you tighten the skewer. the same tension is applied along the entire
length, and the clamping force is the same at both ends. *Reversing the
skewer won't make any difference.

Clamping force would be the same but wouldn't the effective coefficient
of friction be higher steel/steel than aluminum/steel? *or do I not have
my head right?

ignor the qr to dropout interface, the qr is just there to produce the
clamping force. The friction to prevent axle slippage is provided on
the inner face of the dropout. If the clamping force is enough to
stop axle rocking it is enough to prevent axle slippage. Preventing
axle slippage by a correctly tightened axle minimises axle bending.
You have no other way of indicating axle bending than by the slippage
in a slotted dropout when sprinting or hill climbing, so use this to
your advantage and tighten up the axle if it happens. Remember how
hard the new position feels.

On Oct 7, 9:24*pm, Jobst Brandt wrote:

As I said, it's not the skewer but rather the dropout that allows the
wheel to come askew or not. *Get rid of the horizontal slotted
dropouts and note that bending fore and aft is easy because the
horizontal slot has no support fore and aft. *Just look at the gouges
wear marks on horizontal dropouts.

I agree that that would be the best solution, but at that point it
would probably be as economical to get another frame, as I wouldn't be
doing that work myself. I'm sure that there's some combination of
parts that I could get to work because apparently touring bikes with
horiz. dropouts have been used successfully in the past, even with
freewheel hubs.

nate