Cockpit
Cockpit shall refer to the stem, handlebar, aero bars, bar ends, saddle, seatpost,
and any other part involved in your positioning or body contact areas (minus pedals).
Stem
The stem, "goose neck" as it's also known, is important as a
fitting implement and control device. The older style stems are quill stems
and the newer generation uses threadless technology.
Quill stems - Quill stems insert into the
steer tube of the fork.
A wedge device at the bottom of the stem secures the stem in the fork.
The wedge is tightened with bolt that usually runs the entire length of the quill portion.
They are either 1", 1-1/8", or the rarer 1-1/4" (usually for tandems)
which refers to the diameter of the fork steer tube,
not the diameter of the quill portion. A fork is specifically designed
to be used with quill stems - the fork is threaded to accept the proper headset.
As such, all forks using quill-style stems will have a steel steer tube
because carbon fiber and aluminum cannot be threaded. I have yet to see a
quill stem made from anything but metal.
Threadless stems - Threadless stems wrap around the steer tube of the
fork and do not insert into the fork. They come in a lot more sizes with a large
selection of proprietary versions. Standard sizes are 1" or 1-1/8" but they
have 1-1/4" and other sizes. Steel, aluminum, magnesium, titanium, carbon
fiber, there's something for everyone. Forks are specifically designed for threadless-style
stems and can have steer tubes made from metal or carbon fiber.
General concerns - Threadless and quill stems also have a clamp area for the
handlebars. Recent trends have normalized the 31.8mm handlebar size but 22.2mm,
25.4mm, 25.8mm, 26.0mm, and 26.4mm have seen their time in the spotlight, many still
used today. Now there is a hint of an even larger size - 35mm! Most
newer stems have removable face plates saving the trouble of unwrapping the handlebar tape
and removing the shift/brake lever to change the stem. Great idea.
For a stem to function properly it must be properly sized. This includes the handlebar
clamp area and the steer tube interface. Tolerances are crucial here. Machined stems
will always have the potential to attain much higher tolerances. Forged stems, unless
machined afterwards, are questionable at best. Molded stems - carbon fiber mainly - are
so bad that you don't need a micrometer to measure how poorly made they are due
to gross inconsitencies and poor standards. Quality control could step in but that would
mean more than 80% of some stems would hit the junk pile.
How do you know if you have a good stem? A few things to look for vary with
the stem style. This process assumes the stem is properly sized which, for some
manufacturers, is giving them more credit than their crappy products deserve.
Quill stems should have no burrs in the wedge/stem interface area as this will
prevent it from tightening properly. Nor should there be any on the handlebar clamp.
Cheap quill stems are notorious for leaving casting/forging flash on the stem and
the wedge. Any place the stem or the wedge contacts each other or the steer tube,
and the handlebar clamp area should
be filed, sanded, or radiused to smooth out the ridges, burrs, and flash. Liberal
grease on the wedge/stem/steer tube
surfaces and bolts are a must before installation. Maybe a dollop of carbon paste on
the handlebar clamp area just to be safe.
Threadless stems mostly suffer from sharp edges around the steer tube clamp area
in addition to any on the handlebar clamp area.
While not a concern for yesteryear bikes, the introduction and near complete adoption
of carbon fiber steer tubes on forks has shown the imperfections of bad stems via
severed, incised, damaged, and crushed steer tubes. The sharp edge will cut into
the steer tube almost immediately and slowly work its way deeper into the carbon.
Thin carbon steer tubes, loose headsets, improperly faced/reamed headtubes,
sloppy headset spacers, and bad mechanics can create a very bad situation given the
failure mode of carbon fiber - CATASTROPHIC! Grab that file and start removing them.
Add some grease to all bolts, carbon paste to the handlebar clamp area, and maybe some
grease for the steer tube area.
For a quick comparison, look
at a Thomson stem and compare it to some low-quality stem like any of Ritchey's,
not to pick on them but it is almost a rule in this aspect. Thomson is a precisely machined
stem with clean edges, no burrs, incredibly tight tolerances, and a beautiful
piece of artwork. Ritchey stems
are the exact opposite. Of course Ritchey flat out denies their stems
are anything but the cat's meow, comletely incapable of damaging anything.
What a shame from a company that once held such high
esteem in many people's eyes. You'll need to spend about 10 minutes with a file, radius tool,
or emery cloth to clean up the edges.
Another concern with threadless stems is the facing of the stem. A well-made stem
will have parallel faces on the steer tube clamp area. Poorly made carbon stems,
particularly the ones used by ZIPP, Bontrager, and Giant (and others that use this design,
they are all made by the same crap company and rebranded accordingly)
may have a variance over 1mm from the low to high spots. Not only is this piss poor
maufacturing on a ~$300 stem but the problems it creates never seem to end. Headsets which
will never stay tight, unacceptable flex and movement in the headset components,
unsightly gaps.
The "technical experts" at these companies deny it is a
problem, even saying it is good for the industry,
labeling you a troublemaker (emperor's new clothes anyone). Don't think for a minute these
companies are looking out for your best interests, it's all about money,
quality and quality control are moot points. And they know about it,
I've told them all numerous times. Deliberate, intentional, and malicious FRAUD!
One fool who worked at one of these companies had been riding and selling these
stems for years and was completely taken off guard when he learned that I wasn't
making it up, he selected five random new stems and all of them were junk.
So was the one he was using. He almost seemd to care but I could hear the indoctrination
and brainwashing he had been conditioned to accept preventing him from speaking
further.
Cherry pick he could not, they all sucked. And the company had absolutely no intention
of recalling or fixing the problem. And the asshole shop I worked at had no intention
of doing the right thing, yet another time thrown under the bus for profit. Sorry, Crissy,
I tried to help.
Handlebars, Aero bars, Base bars, Bar ends
Handlebar information coming soon
Saddle
Saddle information coming soon, your sore ass will appreciate it
Seatpost
Seatpost information coming soon