What Bicycle Part Varies Least?

On Thu, 23 Dec 2004 16:18:28 GMT, "Steven M. Scharf"
wrote:

wrote:

What part of a bicycle do you think varies the least? And
why?

Valve cover. I've only ever seen four different kinds.

Dear Steven,

Hmmm . . . for Schrader, I've seen plain plastic, plastic
with a feeble valve-core wrench, metal with a rubber O-ring,
and the same with a good valve-core wrench.

But I expect that you meant caps for Schrader, Presta,
Woods/Dunlop, and . . .

What's the fourth kind that you have in mind?

http://www.sheldonbrown.com/gloss_w.html#valve

Carl Fogel

On Thu, 23 Dec 2004 17:10:04 GMT, "Phil, Squid-in-Training"
wrote:

What part of a bicycle do you think varies the least? And
why?

Cranks and bottom brackets have varied the least. Why do you ask?
Because they always creak, are hard to get perfectly clean, have some
failure mode that is "inherent" in their design, and their designs
themselves will always be changing. Oh yeah, and they always smell funny.

Phil

Dear Phil,

"Because they always creak, are hard to get perfectly clean,
have some failure mode that is "inherent" in their design,
and their designs themselves will always be changing. Oh
yeah, and they always smell funny."

Are we talking about cranks and bottom brackets?

Or about Brooks leather saddles?

Carl Fogel

On Thu, 23 Dec 2004 18:22:24 +0100, "trg"
wrote:

Innertube valves, since tire pumps are standardized. There are just 3
standard types that I've seen.

Dear T.,

Like you, I can only think of three kinds, the Schrader,
Presta, and Woods/Dunlop.

But elsewhere in this thread, Steven Scharf mentions four
kinds of valve covers, so I'm worried that you and I and
Sheldon Brown are missing something:

http://www.sheldonbrown.com/gloss_w.html#valve

Of course, the Woods/Dunlop is pretty much a museum piece,
but still we have floor pumps that come with swollen heads
offering both "standard" choices.

And although the widths are standard, other things vary
surprisingly--short valve and long valve guts, removable for
Slime installation, and either threaded or smooth exteriors.

Carl Fogel

On 23 Dec 2004 10:49:00 -0700, Mark Vieselmeyer
wrote:

wrote:

: What part of a bicycle do you think varies the least? And
: why?

Cable aglets. Either that, or the round thumb-nut thing on a presta valve.

- Mark

Dear Mark,

Hmmm . . . the cable aglets vary in tiny increments for the
various cable-housing widths, don't they?

But your choice of the tiny knurled thumb-nut thing on the
Presta valve is a good one.

(Or so I think. They're not removable, so for all I know the
different companies may be using different tiny threads and
their engineers may get into fist-fights at trade-shows over
whose pitch is superior.)

Carl Fogel

On 23 Dec 2004 10:13:17 -0800, "Marvin"
wrote:

Pedal threads? I can interchange any pedal from anything onto
anything. Well,except kid's bikes.

Saddle rails? Any saddle fits any seatpost (gah, except some old
Brooks things. And Dursley-Pedersen hammocks. And recumbents.).

Cables? The basic Bowden cable can double up for shifting and braking
duty on just about everything. Yeah, the nipples are different but
other than that you can freely whack any cable into any bike and it'll
do the job. My repair kit includes a spare gear cable, because you can
use it as an emergency brake cable at a pinch. Apart from hydro
brakes, that is. And stupid Positron gears. And rod brakes.

Chain pitch! I'm damned if I can think of a bicycle that doesn't use
1/2" chain pitch. Someone tell me I'm wrong...

Dear Marvin,

Pedal threads is pretty good--as long as you have both a
15mm and a 9/16ths wrench handy.

You raise the problems with saddle rails and cables.

Chain pitch . . . that's good.

But there was the 10mm Shimano chain:

http://groups.google.co.uk/groups?hl...com%26rnum%3D1

And purists would quibble that the chain pitch is actually
one of the most annoying kinds of variation on a bicycle. We
replace chains as soon as they change pitch about 1%.

Carl Fogel

On Fri, 24 Dec 2004 06:22:48 +1100, Weisse Luft
wrote:


Surprised no one mentioned spoke nipples. There are only 2 sizes as far
as thread diameter goes and only a few lengths. For the most part, they
are identical.

Dear Weisse,

Hmmm . . . only two different diameters and a couple of
different lengths.

And some spoke nipples are brass and better, while others
are aluminum and not.

And some have internal plastic thread-retention.

And then there's this kind of stuff, according to John
Dacey:

"In addition to their unusual spoke heads, Roval spokes also
have threads that are neither 2.0x56tpi nor 1.8x56tpi. The
Roval spoke nipple that shares this thread format is a
special hex-head nut shaped to nest within a toroidal nylon
support at the inner rim wall."

http://groups.google.co.uk/groups?hl...vra7%404ax.com

Well, for bicycles I suppose that spoke nipples are pretty
standard.

Carl Fogel

On Thu, 23 Dec 2004 18:30:17 +0000, Zog The Undeniable
wrote:

wrote:


What part of a bicycle do you think varies the least? And
why?

Sprockets for fixed-gear bikes. I'm sure Cyclo are still knocking them
out on 19th century presses.

Dear Zog,

Did you mean 1/8th or 3/32" cogs? Dura-Ace, E.A.I., or Soma?
And which of the twelve tooth-counts? (Odd that they don't
go down to 11 teeth.)

http://www.sheldonbrown.com/harris/fixed.html#sprockets

Carl Fogel

In article .com,
"Marvin" wrote:

Pedal threads? I can interchange any pedal from anything onto
anything. Well,except kid's bikes.

Yes, definitely. And the basic design was standardized around 1900 or so.

Saddle rails? Any saddle fits any seatpost (gah, except some old
Brooks things. And Dursley-Pedersen hammocks. And recumbents.).

I agree with this one, but horribly, have seen a seat with stamped steel
rails that were rectangular in cross-section. they were about 2mm wide
and 10mm tall, and thus needed their own special seat post head. There
ar also some nasty lightweight fetish seats that have integrated the
seat and post (Giant even does a TT bike with an integrated frame and
post, but that's another story. You cut it to fit, and you only get one
chance).

Cables? The basic Bowden cable can double up for shifting and braking
duty on just about everything. Yeah, the nipples are different but
other than that you can freely whack any cable into any bike and it'll
do the job. My repair kit includes a spare gear cable, because you can
use it as an emergency brake cable at a pinch. Apart from hydro
brakes, that is. And stupid Positron gears. And rod brakes.



Chain pitch! I'm damned if I can think of a bicycle that doesn't use
1/2" chain pitch. Someone tell me I'm wrong...

Yes and no. Aside from the now-obsolete oddities (1" skip-tooth, Shimano
10mm, etc.), chain has become less standard in the last several years
thanks to new chain width variations. That said, A 7-speed chain can be
made to work on just about anything between a BMX and a 9-speed, so you
can cover virtually any bike made with one of three chains in a pinch,
and with considerable overlap.

Let's talk about bike locations that are becoming more standardized:

1-1/8" threadless stems are looking more and more like the futu I
don't think 1point5 will take off except for a few big-hit single crown
bikes, and to its credit Cannondale adopted the 1.5" standard for its
previously proprietary Lefty head tubes.

Mountain bike BBs have typically come in one or two sizes only, and it
looks like the external-bearing trend may be enough to kill off the
oversized BB movement. Meanwhile, English and Italian BBs persist on the
road side, but French and Swiss have gone away.

Cable brake lever pull comes in only two flavours, and Shimano had a
good reason for creating the second one. Too bad about hydraulic brakes.

And that's about it.

--
Ryan Cousineau, http://www.wiredcola.com
Verus de parvis; verus de magnis.

wrote:

(Odd that they don't go down to 11 teeth.)

Nothing smaller than a 12 can be threaded on to a standard (1.37" x 24 tpi)
hub thread. Some 12t track sprockets even have a special lockring to
provide clearance for the chain.

James Thomson

wrote:

I really like your point about the width of the front wheel
dropout--no Scrooge-like objections come to mind, so I'll
have to rely on the nit-picking legions of rec.bicycles.tech
to think of exceptions.

Older English bikes used 3 3/4", or about 95mm. Moulton Mk3s had a special
narrow (3 1/2") hub. WTB tried to introduce a broad 118mm standard for
off-road, that didn't take. Mavic tried to convert the time-trial world to
80mm in the eighties, but failed. Bromptons use 74mm. New Series Moultons
use 70.

Many front hubs (Cannondale Lefties, for instance) are attached on only one
side. I'll leave you to figure out how they should be measured.

James Thomson