shaft drive math

UGH! a chain box? UGH UGH me m,ake chain box! yeah this is too much of
a habit...

so how long does it last?

since i have no idea exactly what it is that I'm speaking of i'll
continue:

if the 299 shaftwal had vovlo steel and german bearings-then how long
would it last
would it last 10,000 miles?

at what cost?

the idea springs from the next to nothing cost of chinese labor-that's
the 299-what the next to nothing labor cost could do to the shaft math
in the second post up-
costs for chain/clusters over X miles(timkens and volvo steel) gives
what savings?

maybe we'll not know-swedish steel german steel ufo japanese steel from
the late '70's is not in great supply-costs may be outasight?

welding Ti tubes together is not the same manufacture as cutting those
hard steel gears and gathering the bearings.

but sounds lika good deal.

how long does it take to redo a flat?

Jobst.Brandt said:

Quoted message said:

Obsolescence is not a matter of mechanical efficiency.

Obsolescence is the act of becoming obsolete.

Therefore the act of becoming obsolete is not a matter of mechanical
efficiency.

Quoted message said:

Obsolescence and obsolete are two different words
and have different meanings.

Similarly, "obfuscation" and "obfuscatory" are two different words with
different meanings: you are being obfuscatory with your obfuscation, above.

--
"Bicycling is a healthy and manly pursuit with much
to recommend it, and, unlike other foolish crazes,
it has not died out." -- The Daily Telegraph (1877)

A Muzi said:

Quoted message said:

Quoted message said:

I believe Mr Brown's choice of words is correct in that
while one might indeed make or buy a shaft drive, there's
little point, chain being so much more efficient.

Obsolescence is not a matter of mechanical efficiency.

At one time a shaft drive made perfect sense, chain being crude.

Chain in the nineteenth century was no more crude than gears at the
time; both technologies made considerable progress in the century
following, but neither has ever been palpably better or worse than the
other.

--
"Bicycling is a healthy and manly pursuit with much
to recommend it, and, unlike other foolish crazes,
it has not died out." -- The Daily Telegraph (1877)

David L. Johnson said:

Hmm. Buggy whips are still available, as are outhouses, hand pumps

for

Quoted message said:

wells, tubular tires 8^), 8-track tapes, vinyl LP's, and many other
obsolete things. OK, maybe there aren't any 8-tracks still

available, I

Quoted message said:

really don't know.

Geez, you'd think you never heard of search engines:
http://www.8trackheaven.com/

Jeff

no-its deliberate
inside out outside in
torus torus

local (and unidentified)bs has unidentified shaft drives lasting from
"broke on first ride" to "lasts forever"

one wonders how long this post should ride before an owner or two
shuffles in?

Meb axed:

Quoted message said:

How about in satisfying the Rube Golbergian technogeek pangs?

Shaft drive is as conservative as Jesse Helms compared to some *real*
Rube Goldberg technology:

http://www.purdue.edu/UNS/html4ever/2004/050305.Rube05.localwin.html

--
"Bicycling is a healthy and manly pursuit with much
to recommend it, and, unlike other foolish crazes,
it has not died out." -- The Daily Telegraph (1877)

Quoted message said:

The Bush fiasco in Florida killed that possibility.

I can't resist. Why is this the "Bush fiasco" instead of the "Gore fiasco?"

--
Dave, who thinks both parties are equally lovable
dvt at psu dot edu

Quoted message said:

Benjamin Lewis said:

Quoted message said:

>> Many obsolete devices are still made for those who still need
>> such things in spite of their loss of general usefulness.
>> Hollerith punch cards are still available but completely
>> obsolete.

Quoted message said:

Quoted message said:

> You're kidding, really? Who still sells them? Who still uses
> them?

Quoted message said:

Quoted message said:

Until the last election our votes were recorded on these and no one
ever saw a dangling chad in our precinct.

Quoted message said:

Now that you mention it, that actually seems like a reasonable use
for them, since they can be read by humans as well as machines, and
they're somewhat less vulnerable to, say, EM radiation.

Too late. The Bush fiasco in Florida killed that possibility. I also
believe the punch card ballots were far better than any replacements,
especially the no-backup, not tamper proof, electronic voting that has
replaced it in this area.

Gee, ya think?!?!?

Calling it the "Bush fiasco" pretty well tells me you were on the side that was
shrieking hysterically that the cards couldn't be trusted and that we must
immediately replace everything with whatever's new.

So now what, shriek that getting rid of the cards is a bad idea?

Screw a bunch of Dems. They lost and then lost again. Complaining about the
machines just makes it worse.

Myself, I'd favor something with punched mylar tape, or even better stainless
steel cards. Expensive, but let's see some Democrat poll worker try sticking a
scribe through the "correct" hole on a stack of those babies. Unfortunately,
there wasn't time for that, because "something must be done NOW." That was the
hue and cry. Bunches of "outraged" Democrats screamed for a new system.
Something electronic and so simple even their constituents could use the things.
Well they got it. For an electronic system it isn't unreasonable to go to the
ATM makers, they do have a pretty damn good record. Of course being businessmen
those people are known Republicans. The horror. So go ahead and complain and
then complain, again, when your guys lose, again. And blame the machines or
whatever. Just don't bother picking sane candidates and policies. That couldn't
be it.

Ron

On Wed, 27 Apr 2005 11:49:05 -0400, Sheldon Brown <[email hidden]>

Quoted message said:

A*** M*** incautiously blurted out:

Quoted message said:

...vacuum tubes are obsolete...

Oh-oh, now you're gonna get it from the diehard fans of SDEEFEDs.

(Silicon Dioxide Encapsulated, Evacuated Field-Effect Devices)

And you thought there were retro grouches in the bike world...

That's right, and that's GloFETs.

Hollow state devices are still the better tool for amplifying audio. To date
there is still no more linear an amplifying device than a triode. Yah, you heard
me right and I know what I'm talkin' 'bout.

You did well to warn them Sheldon, lest I go off on a rant. 🙂

Ron

Quoted message said:

Sheldon "Duck And Cover!" Brown
+---------------------------------------------------+
| In theory, there's no difference between theory |
| and practice; but, in practice, there is. |
+---------------------------------------------------+,
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

butbutbut i spend 3 hours a week maintaining my commuter! before it
goes on the frittzzzz!
how's that sound?

dvt said:

Quoted message said:

The Bush fiasco in Florida killed that possibility.

I can't resist. Why is this the "Bush fiasco" instead of the "Gore fiasco?"

2 Bushes, 1 Gore.

Jasper

On Tue, 03 May 2005 15:06:30 GMT, RonSonic <[email hidden]>

Quoted message said:

Hollow state devices are still the better tool for amplifying audio. To date
there is still no more linear an amplifying device than a triode. Yah, you heard
me right and I know what I'm talkin' 'bout.

Linear. A tube. You know that you're the very first hollow state fan who's
tried to sell *that* one to me? Everybody else just claims they *like* the
distortion.

Jasper

Jasper Janssen said:

On Tue, 03 May 2005 15:06:30 GMT, RonSonic <[email hidden]>
wrote:

Quoted message said:

Quoted message said:

Hollow state devices are still the better tool for amplifying audio. To date
there is still no more linear an amplifying device than a triode. Yah, you heard
me right and I know what I'm talkin' 'bout.

Quoted message said:

Linear. A tube. You know that you're the very first hollow state fan who's
tried to sell *that* one to me? Everybody else just claims they *like* the
distortion.

The tube operates on a 3/2 power law [1], FETs on a square power law,
and BJTs are exponential. Tubes are fundamentally more linear.

On the other hand, just like frame materials in bikes, the circuit
design plays a large part in an amplifier's linearity. And the
audibility of these distortions is not something I know about.

http://www.birotechnology.com/articles/VTspice.html

--
Dave
dvt at psu dot edu

dvt said:

Jasper Janssen said:

On Tue, 03 May 2005 15:06:30 GMT, RonSonic <[email hidden]>
wrote:

Quoted message said:

Quoted message said:

Hollow state devices are still the better tool for amplifying audio.
To date
there is still no more linear an amplifying device than a triode.
Yah, you heard
me right and I know what I'm talkin' 'bout.

Quoted message said:

Linear. A tube. You know that you're the very first hollow state fan
who's
tried to sell *that* one to me? Everybody else just claims they *like*
the
distortion.

The tube operates on a 3/2 power law [1], FETs on a square power law,
and BJTs are exponential. Tubes are fundamentally more linear.

On the other hand, just like frame materials in bikes, the circuit
design plays a large part in an amplifier's linearity. And the
audibility of these distortions is not something I know about.

http://www.birotechnology.com/articles/VTspice.html

The fact that one amplifier component or another is "more linear" is not
really important. Given that all devices are non-linear, the circuit
design must compensate for these non-linearities. The circuit designer's
task is to build a perfect amplifier out of imperfect materials. The
degree of imperfection is less important in reality than the ability to
compensate for it. (aluminum is weaker than steel, but it's lighter, so
you can use more of it).

Some imperfections are very difficult to compensate. Frequency response,
for instance. If a component physics dictate it can't amplify fast
enough, there may be no way to faithfully amplify high frequencies
because that behavior can't be compensated for. Other imperfections,
like thermal drift or gain change with power level (simple
non-linearity) can be compensated with clever circuit designs.

There are some very large intrinsic imperfections to vacuum tube
technology. Perhaps the largest is that tubes (being field effect
devices) work best at high voltages and low currents, while
loudspeakers, inconveniently, work best at high currents and low
voltages. The only solution to this mismatch is to use a transformer, so
tube amplifier design becomes transformer design.

Since tube amplifiers were historically much inferior on standard
benchmarks (frequency response, harmonic distortion, etc.), and
transistor amps were cheaper, and much more reliable, the tube market
died until resurrected by fad. Since tube amps are still inferior by
benchmark, the tube fans simply discard the benchmarks as inaccurate and
rely on subjective evaluations. The parallels to the bike market are
hard to miss.

Jasper Janssen said:

On Tue, 03 May 2005 15:06:30 GMT, RonSonic <[email hidden]>

Quoted message said:

Hollow state devices are still the better tool for amplifying audio. To date
there is still no more linear an amplifying device than a triode. Yah, you heard
me right and I know what I'm talkin' 'bout.

Linear. A tube. You know that you're the very first hollow state fan who's
tried to sell *that* one to me? Everybody else just claims they *like* the
distortion.

So they're wrong. Or rather they are oversimplifying.

Tubes are inherently low distortion devices that are typically used in circuits
without much or any negative feedback to null distortion. Transistors typically
distort terribly but have tremendous amounts of gain and so are conveniently
used in circuits that have massive amounts of negative feedback which purports
to reduce distortion for the entire amplifier.

The debate goes on and on. In short, the levels of measured distortion for
either amp are minimal and not worth arguing over. To debate the relative merits
of an amp with 1% distortion versus 0.1% is arguing trivia. At the higher figure
an amp with almost exclusively higher order odd distortion products will be
objectionable, but that simply isn't what you find in a well designed amp, so
let's ignore that too.

I will argue that an amp's overload behavior is important since nearly any
normal amp will be driven to it's peaks from time to time. There, tubes do
nicely, not so much because their distortion products sound good but that they
don't sound horrid. See previous comments about higher order harmonic products.

In any case, neither is going to distort enough that you'll hear the distortion
as such. There's not a speaker on earth that doesn't distort much more than the
amps.

Anyway, other than a handfull of FETs no solid state device is as linear as a
triode. It is the amplifier topology with large amounts of distortion cancelling
negative feedback that produces lower measured amounts of distortion.

Ron

RonSonic said:

Not so much discard the benchmarks as recognize them to be extremely limited.
THD + Noise is a benchmark because it is easy, not because it tells us anything
about how that amp is going to sound, short of it being horrid. One cannot
distinguish between a so-so system and a brilliant one on the basis of the
standard tests.

If the standard tests are rejected but not replaced with anything, then
they're discarded. In the absence of objective (quantifiable,
repeatable) tests you just have subjective impressions (opinions).

Quoted message said:

Now that our measurement technology is getting better there's room

for new and

Quoted message said:

better tests, things like FFT using real music rather than a steady state wave.
I think with this we'll start to see measurements of tthe things we've been
hearing all along.

Maybe. I doubt it, myself. Until such time though, you're just speculating.

Quoted message said:

You are very right that its more about the design than the particular technology
used. Still, starting with a low distortion device, one that can be used to
build a passable open loop amp makes things a lot easier.

That is a very different point of view than I was taught in EE school or
experienced back in the days when I designed the occasional amplifier. I
don't think I ever built an open loop anything, not even a power supply.
I think it's simplistic pseudo-science.

Quoted message said:

Sorta like steel
frames, really was a great way to build a bike in the first place and nothing
objectively better has come along. Only things with different trade-offs and
compromises.

I couldn't disagree more. Carbon fiber composite is a much better
material, just as transistors are much better components. Carbon fiber
is more costly to build bike frames with, but transistors are much
cheaper. Those facts are the realities that have created current market
share -- that and the retro-grouch segment that doesn't hear anything
but what they want to, with steel or glass tubes.

RonSonic said:

That's right, and that's GloFETs.

Hollow state devices are still the better tool for amplifying audio. To date
there is still no more linear an amplifying device than a triode. Yah, you heard
me right and I know what I'm talkin' 'bout.

You did well to warn them Sheldon, lest I go off on a rant. 🙂

Ron

Were'nt more linear tretrode and pentode tubes developed to minimize the electron charge clouds that developed between electrodes?