Chain outside widths?

In article <[email hidden]>,

Joe Riel said:

Tim McNamara said:

I know that tends to sound impressive, but many tourists put out as much or more power
than pros.

Highly doubtful. Power, no; chain tension, yes. As you said, tourists can generate higher chain
tension because they have much smaller gears [and weigh more].

Pros are faster than tourists, generally speaking, and the naturalistic assumption tends to be that
pros have higher power output.

Yet this is not really the case. For example, I have been tested on an ergometer to have a higher
peak power output than many pros at around 1050 watts. My output at lactate threshold was about 400
watts, IIRC. But being 6'4" and weighing 205 lbs, my power to weight ratio is much worse than even
the lowest ranked pros. My body fat is about 12%, the average pro is about 5%. Additionally, my VO2
max is about 60% of Lance Armstrong's. Therefore I'm nowhere near as fast as the slowest pros let
alone the best.

IMHO the pros are faster than tourists not because of power output alone but because of
power-to-weight and VO2 max issues. Pain threshold, lactate tolerance and motivation probably also
are significant factors. Efficiency may also be a factor- I ride about 6,000 miles most years
whereas most pros ride at least two to three times as many miles. I would presume that they are more
efficient in the mechanics of riding a bike than I am as a result.

Even within pro cycling one sees differences. Mario Cipollini certainly produces much more power
than Marco Pantani, as is evident in their relative sprinting abilities- yet Cipo can barely get
over the mountains with the back of the bunch while Pantani is soaring away off the front.

A number of years ago, the USCF went around the country with a test rig and tried people out at
random. I remember a report in the USCF magazine that they found some guy in a mall who hit nearly
1400 watts in a sprint simulation- in Birkenstocks. That's like Mario Cipollini type output. They
found lots of people who could post excellent power numbers, numbers consistent with pro cyclists-
yet few if any were able to be top-level racing cyclists.

In article said:

Tim McNamara said:

I know that tends to sound impressive, but many tourists put out as much or more power
than pros.

That doesn't sound impressive, that sounds ridiculous. If you see a tourist that can generate 400
watts for an hour, you're not looking at a tourist.

Dunno- a lot of the guys I saw at PBP this year seemed to be able to put out that kind of sustained
power. A lot of this is simply what an individual has the biological capacities to do.

In article <[email hidden]>,

Joe Riel said:

Tim McNamara said:

In article <[email hidden]>,

Joe Riel said:

Tim McNamara <[email hidden]> writes:

> I know that tends to sound impressive, but many tourists put out as much or more power than
> pros.

Highly doubtful. Power, no; chain tension, yes. As you said, tourists can generate higher
chain tension because they have much smaller gears [and weigh more].

Pros are faster than tourists, generally speaking,

I think you can drop the qualification. Pros are faster than tourists.

It's horses for courses. Tourists can finish Paris-Brest-Paris (1215 km) in under 44 hours. Not sure
that all that many pros could do it faster. I think I may be using a broader definition of "tourist"
than you are. I'm also not sure that many pros would be much faster than many fit tourists with 60
lbs of luggage on the bike.

Quoted message said:

Quoted message said:

naturalistic assumption tends to be that pros have higher power output.

Yet this is not really the case. For example, I have been tested on an ergometer to have a
higher peak power output than many pros at around 1050 watts.

I don't doubt that there are people who can put out more instantaneous power than quite a few, if
not all, the pros, however, I wouldn't say that they are cycling tourists riding as tourists. That
is, in a typical professional bike race, the peak power output of any [yes, that's too general,
but...] of the pros is higher than the peak power output of a cycling tourist while touring.

Not having specific numbers I can't confirm or refute that. I'll say that I disagree with
it, however.

Power output of pros has been measured (for example, it was published in- IIRC- VeloNews that power
testing showed that a rider riding a flat stage in the Tour de France in the pack averages about 95
watts) but at least as far as I know there hasn't been a lot of measurement of tourists.

Dan O'Brasky said:

why would you revert to 10 year discontinued components. No there is absolutely no advantage to
this and no there is no strength advantage to yesterday's chains. In fact the old ones are weaker
and made from inferior alloys.

You've been smoking too much slick print, brother.

Bike chains never fail from overtension, but from excessive wear or rivet damage at the
sideplates. 9-speed chains are much worse than 7-speed ones in both these respects, having less
projected bushing area and more aggressively riveted links. Even if the alloys used are better
than in days past, which I doubt, the overall reliability of chains has diminished since the days
of Sedis chains.

Quoted message said:

Indeed you first should invest in an avid rollamajig ($20) and get an adjustment. The more cogs
the better with smoother transitions possible.

If 7-speed (or 6-speed, or whatever) gives overall range and incremental steps that are acceptable
to the rider, then adding more rear sprockets hurts reliability in several ways-- accelerating chain
and sprocket wear, requiring more precise adjustment to deliver clean shifting, unfavorably
modifying chainline, and weakening the rear wheel with excessive dish. It also dramatically
diminishes cross-compatibility of components.

Chalo Colina

"Tim McNamara" <[email hidden]> wrote in message
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Quoted message said:

In article <[email hidden]>, "Richard Goodman"

Quoted message said:

I don't think you can say nine speed chains are fragile or weak. Even ten speed chains can take
the power output of the likes of Armstrong and Ullrich, or if you prefer, the output of any of
the leading off-road XC riders, whoever they are. Used correctly, your chain and gears are
surely able take all the power you're capable of putting through it.

I know that tends to sound impressive, but many tourists put out as much or more power than pros.
Pros have a high power to weight ratio, tourists do not even though their absolute power may be
every bit as much as the pros. Their chains are under higher tension because they're winching a
lot more weight up the hills- not unusual for a touring bike and rider with luggage to weigh 2 to
2 1/2 times a pro on a pro-caliber bike.

The difference is that for a given force on the pedal, a touring bike using a 22-tooth small
chainring puts more stress on the chain than a road bike with a 39-tooth small chainring. 39/22
times as much. However, even a good sprinter isn't going to get near the breaking point of a
derailleur chain. See, for example, rohloff.deindex.phpOpen ↗, where
Rohloff give the elastic limit of their derailleur chain as >7000N and the failure point as >11000N.

Nick

(Chalo) said:

If 7-speed (or 6-speed, or whatever) gives overall range and incremental steps that are acceptable
to the rider, then adding more rear sprockets hurts reliability in several ways-- accelerating
chain and sprocket wear, requiring more precise adjustment to deliver clean shifting, unfavorably
modifying chainline, and weakening the rear wheel with excessive dish.

Uh-huh. And when you've got a nine-speed cluster on one side and a disk on the other, the dish on
the rear wheel is beginning to look worryingly slight.

I'll give it some thought. I think a seven speed rear probably is enough for me.

--
[email hidden] (Simon Brooke) jasmine.org.uk~simonOpen ↗

Iraq war: it's time for regime change... ... go now, Tony, while you can still go
with dignity.

"Simon Brooke" <[email hidden]> wrote in message
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Quoted message said:

(Chalo) said:

If 7-speed (or 6-speed, or whatever) gives overall range and incremental steps that are
acceptable to the rider, then adding more rear sprockets hurts reliability in several ways--
accelerating chain and sprocket wear, requiring more precise adjustment to deliver clean
shifting, unfavorably modifying chainline, and weakening the rear wheel with excessive dish.

Uh-huh. And when you've got a nine-speed cluster on one side and a disk on the other, the dish on
the rear wheel is beginning to look worryingly slight.

It may be worth bearing in mind that the majority of tandems these days come with 9 speed, and it
works for them. (although the XT cassettes aren't strong enough for off road use - the
recommended ones are HG70, and the XT freehubs are also a bit fragile. But the chain hasn't given
any problems yet!).

cheers, clive

Quoted message said:

It may be worth bearing in mind that the majority of tandems these days come with 9 speed, and it
works for them.

But surely with wider hubs overall, which leaves more room for extra sprockets?

I just picked up a couple of spare 7-speed hubs before they're all gone.
--
David Damerell <[email hidden]> Distortion Field!

"David Damerell" <[email hidden]> wrote in message
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Quoted message said:

Quoted message said:

It may be worth bearing in mind that the majority of tandems these days

come

Quoted message said:

Quoted message said:

with 9 speed, and it works for them.

But surely with wider hubs overall, which leaves more room for extra sprockets?

Not my MTB tandem - 135mm (the road one is 140mm). But the OP was worried about chain and cog
strength, for which the hub width is irrelevant.

cheers, clive