What is this screw?

I was looking at a coworker's bike today and noticed that it has an
interesting 'braze-on' that I've never seen before. On the bottom of
the top-tube there is a single small screw, similar to a waterbottle
screw about 1/4 of the way back from the headtube.

The bike is a 2007 (??) Orbea Opal...
http://www.orbea-usa.com/smallpic/Op...big_orange.jpg

If you look at this picture you can see the screw sticking down just
under the A on the top tube...

I've been stumped about this all morning. :-)

--
Work and recreation are not often effected at the same time.
One using a bicycle in business makes an exception to the rule.
- Dr. Edgar H. Earl, Rochester. (~1892)

On Aug 15, 2:44*pm, Rex Kerr wrote:
I was looking at a coworker's bike today and noticed that it has an
interesting 'braze-on' that I've never seen before. *On the bottom of
the top-tube there is a single small screw, similar to a waterbottle
screw about 1/4 of the way back from the headtube.

The bike is a 2007 (??) Orbea Opal...http://www.orbea-usa.com/smallpic/Op...big_orange.jpg

If you look at this picture you can see the screw sticking down just
under the A on the top tube...

I've been stumped about this all morning. :-)

It's for hanging a number plate as used in
pro bike racing. Recently, the number is sometimes
attached behind the seatstays instead. I think
with the advent of funny shaped carbon tubing,
race bikes don't all have this braze-on anymore.

Here, you can see that poor Tom Boonen couldn't
afford a braze-on in 2007 and they had to zip-tie
his number on:
http://www.cyclingnews.com/photos/20...oonenBikeGreen

Ben

On Aug 15, 3:44 pm, Rex Kerr wrote:
I was looking at a coworker's bike today and noticed that it has an
interesting 'braze-on' that I've never seen before. On the bottom of
the top-tube there is a single small screw, similar to a waterbottle
screw about 1/4 of the way back from the headtube.

The bike is a 2007 (??) Orbea Opal...http://www.orbea-usa.com/smallpic/Op...big_orange.jpg

If you look at this picture you can see the screw sticking down just
under the A on the top tube...

I've been stumped about this all morning. :-)

--
Work and recreation are not often effected at the same time.
One using a bicycle in business makes an exception to the rule.
- Dr. Edgar H. Earl, Rochester. (~1892)

Its to let out some of the energy accumulated during a hard ride so
that the frame will not get weaker with time. In regular frames, the
accumulated energy from the efforts made during the ride is stored
inside the frame. If you don't let that energy out, it presses against
the walls and weakens them. After a while, the frames get more and
more flexible and eventually they break. That is the reason that steel
frames get weaker and more flexible with time. The same is true for Al
and CF frames, but these are guaranteed only for 3 to 5 years, so
people usually discard them. Because steel frames are guaranteed for
life, people keep them for many years. However, they get more flexible
with time. If you clean the bike regularly, the negative energy will
be release when you remove the seatpost, bb etc. But, most people
don't do this often enough.

Orbea has solved the problem with this hole. You can leave the screw
slightly opened and allow some of the energy to be released as you
ride. Or you can unscrew the screw at the end of each ride and let the
energy come out all at once. If you choose to keep the screw slightly
open to let energy release, you run the risk of loosing some of the
energy that propels the bike. This is especially true during hard
efforts. When you ride this sort of bike after releasing all the
energy, it will fleel as if it was brand new.

Hope that this was useful,

Andres

In article 76906c10-abc8-43c5-8b88-09ad3c1d9726@
34g2000hsh.googlegroups.com, says...
Its to let out some of the energy accumulated during a hard ride so
that the frame will not get weaker with time.

And here I thought it was for tuning the frame's ride characteristics!
Silly me!

Java

On Aug 15, 6:25*pm, Espressopithecus (Java Man)
wrote:
.googlegroups.com, says... Its to let out some of the energy accumulated during a hard ride so
that the frame will not get weaker with time.

And here I thought it was for tuning the frame's ride characteristics! *
Silly me!

You're thinking of the Helios helium port that's used on TT bikes.
That's the fastest way to fine tune a bike's weight. You do have to
be careful as adding too much at once can freeze a carbon frame - they
shatter something fierce!

R

Rex Kerr wrote:
I was looking at a coworker's bike today and noticed that it has an
interesting 'braze-on' that I've never seen before. On the bottom of
the top-tube there is a single small screw, similar to a waterbottle
screw about 1/4 of the way back from the headtube.

The bike is a 2007 (??) Orbea Opal...
http://www.orbea-usa.com/smallpic/Op...big_orange.jpg

If you look at this picture you can see the screw sticking down just
under the A on the top tube...

I've been stumped about this all morning. :-)

It's for a race number. Giant bikes sometimes have them too.

Zog The Undeniable wrote:
It's for a race number. Giant bikes sometimes have them too.

Ah... see, I don't follow racing so I had no clue. That also explains
why none of *MY* bikes have ever had such a screw! :-)


--
Work and recreation are not often effected at the same time.
One using a bicycle in business makes an exception to the rule.
- Dr. Edgar H. Earl, Rochester. (~1892)

On Aug 15, 3:05*pm, " wrote:
On Aug 15, 3:44 pm, Rex Kerr wrote:





I was looking at a coworker's bike today and noticed that it has an
interesting 'braze-on' that I've never seen before. *On the bottom of
the top-tube there is a single small screw, similar to a waterbottle
screw about 1/4 of the way back from the headtube.

The bike is a 2007 (??) Orbea Opal...http://www.orbea-usa.com/smallpic/Op...big_orange.jpg

If you look at this picture you can see the screw sticking down just
under the A on the top tube...

I've been stumped about this all morning. :-)

--
Work and recreation are not often effected at the same time.
One using a bicycle in business makes an exception to the rule.
* * * *- Dr. Edgar H. Earl, Rochester. *(~1892)

Its to let out some of the energy accumulated during a hard ride so
that the frame will not get weaker with time. In regular frames, the
accumulated energy from the efforts made during the ride is stored
inside the frame. If you don't let that energy out, it presses against
the walls and weakens them. After a while, the frames get more and
more flexible and eventually they break. That is the reason that steel
frames get weaker and more flexible with time. The same is true for Al
and CF frames, but these are guaranteed only for 3 to 5 years, so
people usually discard them. Because steel frames are guaranteed for
life, people keep them for many years. However, they get more flexible
with time. If you clean the bike regularly, the negative energy will
be release when you remove the seatpost, bb etc. But, most people
don't do this often enough.

Orbea has solved the problem with this hole. You can leave the screw
slightly opened and allow some of the energy to be released as you
ride. Or you can unscrew the screw at the end of each ride and let the
energy come out all at once. If you choose to keep the screw slightly
open to let energy release, you run the risk of loosing some of the
energy that propels the bike. This is especially true during hard
efforts. When you ride this sort of bike after releasing all the
energy, it will fleel as if it was brand new.

Hope that this was useful,

Andres- Hide quoted text -

- Show quoted text -

Wat a bunch a nonsense, mon. You tinking of the OBEAH bike, not Orbea.
On Obeah bikes you open da little screw to let out da evil spirits,
mon.
Bike, bike, bike, meow,
ABS

Rex Kerr wrote:
I was looking at a coworker's bike today and noticed that it has an
interesting 'braze-on' that I've never seen before. On the bottom of
the top-tube there is a single small screw, similar to a waterbottle
screw about 1/4 of the way back from the headtube.

The bike is a 2007 (??) Orbea Opal...
http://www.orbea-usa.com/smallpic/Op...big_orange.jpg

If you look at this picture you can see the screw sticking down just
under the A on the top tube...

I've been stumped about this all morning. :-)

Racing number mount

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971
** Posted from http://www.teranews.com **

On Aug 15, 5:02*pm, Zog The Undeniable wrote:
Rex Kerr wrote:
I was looking at a coworker's bike today and noticed that it has an
interesting 'braze-on' that I've never seen before. *On the bottom of
the top-tube there is a single small screw, similar to a waterbottle
screw about 1/4 of the way back from the headtube.

The bike is a 2007 (??) Orbea Opal...
http://www.orbea-usa.com/smallpic/Op...big_orange.jpg

If you look at this picture you can see the screw sticking down just
under the A on the top tube...

I've been stumped about this all morning. :-)

It's for a race number. *Giant bikes sometimes have them too.

Darn, my explanation was much more colorful.