Do cyclists make better motorcyclists?

On Tue, 7 Sep 2004 13:00:15 -0700, "Tom Nakashima"
wrote:


wrote in message
.. .
On Tue, 7 Sep 2004 10:30:38 -0700, Bill Lloyd
wrote:

On 2004-09-06 17:51:47 -0700, "Trevor" said:


wrote in message ...
It gets worse at higher speeds. Here's a table for the same
bike on a 17% grade, where it reaches 70.1 mph and needs 204
rpm to engage a 2124 mm 700c tire with 54 x 12 gearing:

mph rpm watts
70.1 0 0 coasting, not pedalling
62.6 204 0.1 coasting, but pedalling w/no power
70.1 204 1046 pedalling 52 x 12 gear


I think it was E. Merckx whose measured o/p was 1 1/3 hp or 1700Watts
which is 650 watts more than that required for 70mph. High power is
produced at high rpm so a slower cadence is not required.

Merckx might have maxed at 1700 watts (actually, I doubt it), but
that's something he could maintain for 5 seconds. So there's no way
he'd be doing that on a descent.

Also, 204 RPM is ridiculous... nobody is going to sustain that sort of
cadence for more than a few seconds. Certainly you won't be making
good power at that RPM (of course, these days you'd use a 53x11 instead
of a 52x12, that's silly gearing if you're going down a big downhill
fast, welcome to the 90's).

Not all riders are alike, at what speed would 1700watts attain on a
1in10
grade with this calculator. Use 53x12 700x25C 167.5 cranks, flat back.

Not physically possible, even for Merckx. Because, recall, to go that
70.1 mph you have to do the work of accelerating from 60 mph to 70 mph
by pedaling.

And a 17% grade? Where are you going to find a sustained 17% grade?

Dear Bill,

The closest thing to a sustained 17% grade in Wales appears
to be Bwlch-y-Groes (not the Bwlch Trevor mentioned):

http://www.salite.ch/groes1.htm

There's 2 km of 16% grade at the top. It's much steeper than
any of the 53 other grades in Wales listed at:


http://ciclismo.sitiasp.it/motore.as...ngua=eng&da=az

Unfortunately, the site just shows a distance versus
altitude graph, so there's no easy way to tell if turns make
high speed descents impossible..

Trevor, of course, claims to have hit 70 mph on what he
judges to be only a 10% grade, not the 17% that I used for
my example. (Wales is awfully short of 10% grades, judging
by the site above, which doesn't mention the A494 road as
having outstandingly steep sections.)

Trevor eventually remembered a tailwind of less than 10 mph
that was later upgraded to 15 mph.

He also proposes some drafting theories that don't seem to
be exactly air-tight, if you'll pardon the pun.

Riders can reach 70 mph just by coasting, given some
combination of grade, weight, and tailwind.

But Trevor claims to have reached 70 mph routinely by
pedalling a 52 x 12 at 200 rpm on a stretch of Welsh road
whose grade he claims is about 10%.

I'm skeptical, but I think that his 70 mph claim may be a
little more likely than his claim that a sprinting rider was
swerving ten feet from side to side when the gearing
produced only 12.5 feet of forward movement with each stomp
on the pedal.

Or than his claim that any decent sprinter can reach 50 mph
on level ground (Mark McMaster pointed out that the flying
200 meter sprint record is just under ten seconds--only 45.4
mph.)

Or than his claim that both his tires routinely came off the
ground at the same time during sprinting in a sort of
kangaroo-hop tribute to his wheel-building technique, power,
and poor form.

Or than his claim that he has a wheel with spokes worn a
third of the way through where they cross.

Or . . . well, you get the idea.

Carl Fogel

So what's your point Carl? That Trevor is a liar?
Or you enjoy playing Perry Mason to this group?
I think some people really need to get a life here.
Makes me wonder when they have time to actually ride.
If he says he gone 70 mph then so what? He could say he's gone 100 mph and
I wouldn't even bat an eyelash.
-tom

Dear Tom,

My point is that although 70 mph is quite possible, given
the right combination of grade, weight, tailwind, and
possibly amazing pedalling, an awful lot of claims look
implausible when we ask for details.

Asking for details and pondering the replies is how I learn
more about this sort of thing. Until I pursued the question,
I would have dismissed any claim by Chalo Colina that hecan
easily hit much higher speeds downhill than the rest of us.

But now I know that a bicycle and rider weighing 400 pounds
really can roll down a modest hill at ungodly speeds.

I also have a theory that the Fury RoadMaster rolls down my
daily hill roughly as fast as my touring bike, despite the
handicap of its huge, soggy tires because of its extra mass.

And I've learned why the damn bike always slows down a
little when I start pedalling on the runout from a good
hill, no matter how hard I try to stay tucked in--pedal
motion increases wind drag.

In short, I want to know why I bat an eyelash and whether I
should be raising my eyebrows.

When I first saw Jobst's absurd claim that bicycles stand on
their lower spokes, my eyebrows turned into a handsome
toupee. But after I pondered things and read what other
people said, my eyebrows descended enough for me to scratch
my bald head and eventually admit that Jobst seems to be
right.

Right now, I have one eyebrow lifted about spoke-squeezing
stress-relief claims. Some days, it lowers a little, but on
other days it's joined by the other eyebrow. Right or wrong,
the theory does come from someone with a history of being
right about a lot of bicycling physics.

Whether Trevor is Baron Munchausen on a bicycle or the
victim of unjustified doubts, it's still interesting to look
into his claims.

(The real baron wasn't what the book made him out to be:

http://www.fact-index.com/b/ba/baron_munchhausen.html

See how interesting a little poking around can be?)

IfTrevor has a picture of the wheel with the spokes worn a
third of the way through, then that will be damned
interesting. Wouldn't you click on a link to a picture of
something like that?

Or a picture of a sprinter with both tires coming off the
ground? Or a diagram of how a sprinter can swerve ten feet
sideways as he stomps down on a pedal? Or a link to a site
that explains how to reach 50 mph on a level course? Or a
post from some of Trevor's fellow riders testifying to their
amazing speeds ten years ago in the Welsh countryside?

Unfortunately, a Welsh corgi seems to be thriving on a diet
of Trevor's homework. In the latest example, the wheel with
the badly worn spokes can't be found--which gives Trevor
the opportunity to tell us that this missing wheel with the
worn spokes is also the wheel that proved that Jobst is
utterly wrong.

Possibly the wheel is lying under a piece of the true cross?

Or maybe there really is such a wheel and within a month
we'll have some fascinating pictures of what look like badly
worn spokes. ( I'm wondering whether the galvanized spokes
that Trevor favors might corrode at the crossing and then
erode, something that the stainless-steel-spoke-folk of
rec.bicycles.tech wouldn't be likely to encounter.)

But so far I can't see the cannonball that Trevor rode to
the moon on the A494. Or how he pulled himself past those
riders at 70 mph by his bootstraps. (Read the link above.)

But I do expect that he'll surprise me and that I'll have
fun looking into his future claims. He does seem to have
done a good deal of bicycling, so he might well have some
fascinating points that turn out to be true.

Carl Fogel

On Tue, 7 Sep 2004 13:00:15 -0700, "Tom Nakashima"
wrote:


wrote in message
.. .
On Tue, 7 Sep 2004 10:30:38 -0700, Bill Lloyd
wrote:

On 2004-09-06 17:51:47 -0700, "Trevor" said:


wrote in message ...
It gets worse at higher speeds. Here's a table for the same
bike on a 17% grade, where it reaches 70.1 mph and needs 204
rpm to engage a 2124 mm 700c tire with 54 x 12 gearing:

mph rpm watts
70.1 0 0 coasting, not pedalling
62.6 204 0.1 coasting, but pedalling w/no power
70.1 204 1046 pedalling 52 x 12 gear


I think it was E. Merckx whose measured o/p was 1 1/3 hp or 1700Watts
which is 650 watts more than that required for 70mph. High power is
produced at high rpm so a slower cadence is not required.

Merckx might have maxed at 1700 watts (actually, I doubt it), but
that's something he could maintain for 5 seconds. So there's no way
he'd be doing that on a descent.

Also, 204 RPM is ridiculous... nobody is going to sustain that sort of
cadence for more than a few seconds. Certainly you won't be making
good power at that RPM (of course, these days you'd use a 53x11 instead
of a 52x12, that's silly gearing if you're going down a big downhill
fast, welcome to the 90's).

Not all riders are alike, at what speed would 1700watts attain on a
1in10
grade with this calculator. Use 53x12 700x25C 167.5 cranks, flat back.

Not physically possible, even for Merckx. Because, recall, to go that
70.1 mph you have to do the work of accelerating from 60 mph to 70 mph
by pedaling.

And a 17% grade? Where are you going to find a sustained 17% grade?

Dear Bill,

The closest thing to a sustained 17% grade in Wales appears
to be Bwlch-y-Groes (not the Bwlch Trevor mentioned):

http://www.salite.ch/groes1.htm

There's 2 km of 16% grade at the top. It's much steeper than
any of the 53 other grades in Wales listed at:


http://ciclismo.sitiasp.it/motore.as...ngua=eng&da=az

Unfortunately, the site just shows a distance versus
altitude graph, so there's no easy way to tell if turns make
high speed descents impossible..

Trevor, of course, claims to have hit 70 mph on what he
judges to be only a 10% grade, not the 17% that I used for
my example. (Wales is awfully short of 10% grades, judging
by the site above, which doesn't mention the A494 road as
having outstandingly steep sections.)

Trevor eventually remembered a tailwind of less than 10 mph
that was later upgraded to 15 mph.

He also proposes some drafting theories that don't seem to
be exactly air-tight, if you'll pardon the pun.

Riders can reach 70 mph just by coasting, given some
combination of grade, weight, and tailwind.

But Trevor claims to have reached 70 mph routinely by
pedalling a 52 x 12 at 200 rpm on a stretch of Welsh road
whose grade he claims is about 10%.

I'm skeptical, but I think that his 70 mph claim may be a
little more likely than his claim that a sprinting rider was
swerving ten feet from side to side when the gearing
produced only 12.5 feet of forward movement with each stomp
on the pedal.

Or than his claim that any decent sprinter can reach 50 mph
on level ground (Mark McMaster pointed out that the flying
200 meter sprint record is just under ten seconds--only 45.4
mph.)

Or than his claim that both his tires routinely came off the
ground at the same time during sprinting in a sort of
kangaroo-hop tribute to his wheel-building technique, power,
and poor form.

Or than his claim that he has a wheel with spokes worn a
third of the way through where they cross.

Or . . . well, you get the idea.

Carl Fogel

So what's your point Carl? That Trevor is a liar?
Or you enjoy playing Perry Mason to this group?
I think some people really need to get a life here.
Makes me wonder when they have time to actually ride.
If he says he gone 70 mph then so what? He could say he's gone 100 mph and
I wouldn't even bat an eyelash.
-tom

Dear Tom,

My point is that although 70 mph is quite possible, given
the right combination of grade, weight, tailwind, and
possibly amazing pedalling, an awful lot of claims look
implausible when we ask for details.

Asking for details and pondering the replies is how I learn
more about this sort of thing. Until I pursued the question,
I would have dismissed any claim by Chalo Colina that hecan
easily hit much higher speeds downhill than the rest of us.

But now I know that a bicycle and rider weighing 400 pounds
really can roll down a modest hill at ungodly speeds.

I also have a theory that the Fury RoadMaster rolls down my
daily hill roughly as fast as my touring bike, despite the
handicap of its huge, soggy tires because of its extra mass.

And I've learned why the damn bike always slows down a
little when I start pedalling on the runout from a good
hill, no matter how hard I try to stay tucked in--pedal
motion increases wind drag.

In short, I want to know why I bat an eyelash and whether I
should be raising my eyebrows.

When I first saw Jobst's absurd claim that bicycles stand on
their lower spokes, my eyebrows turned into a handsome
toupee. But after I pondered things and read what other
people said, my eyebrows descended enough for me to scratch
my bald head and eventually admit that Jobst seems to be
right.

Right now, I have one eyebrow lifted about spoke-squeezing
stress-relief claims. Some days, it lowers a little, but on
other days it's joined by the other eyebrow. Right or wrong,
the theory does come from someone with a history of being
right about a lot of bicycling physics.

Whether Trevor is Baron Munchausen on a bicycle or the
victim of unjustified doubts, it's still interesting to look
into his claims.

(The real baron wasn't what the book made him out to be:

http://www.fact-index.com/b/ba/baron_munchhausen.html

See how interesting a little poking around can be?)

IfTrevor has a picture of the wheel with the spokes worn a
third of the way through, then that will be damned
interesting. Wouldn't you click on a link to a picture of
something like that?

Or a picture of a sprinter with both tires coming off the
ground? Or a diagram of how a sprinter can swerve ten feet
sideways as he stomps down on a pedal? Or a link to a site
that explains how to reach 50 mph on a level course? Or a
post from some of Trevor's fellow riders testifying to their
amazing speeds ten years ago in the Welsh countryside?

Unfortunately, a Welsh corgi seems to be thriving on a diet
of Trevor's homework. In the latest example, the wheel with
the badly worn spokes can't be found--which gives Trevor
the opportunity to tell us that this missing wheel with the
worn spokes is also the wheel that proved that Jobst is
utterly wrong.

Possibly the wheel is lying under a piece of the true cross?

Or maybe there really is such a wheel and within a month
we'll have some fascinating pictures of what look like badly
worn spokes. ( I'm wondering whether the galvanized spokes
that Trevor favors might corrode at the crossing and then
erode, something that the stainless-steel-spoke-folk of
rec.bicycles.tech wouldn't be likely to encounter.)

But so far I can't see the cannonball that Trevor rode to
the moon on the A494. Or how he pulled himself past those
riders at 70 mph by his bootstraps. (Read the link above.)

But I do expect that he'll surprise me and that I'll have
fun looking into his future claims. He does seem to have
done a good deal of bicycling, so he might well have some
fascinating points that turn out to be true.

Carl Fogel

wrote in message
...
On Tue, 7 Sep 2004 13:00:15 -0700, "Tom Nakashima"
wrote:


wrote in message
.. .
On Tue, 7 Sep 2004 10:30:38 -0700, Bill Lloyd
wrote:

On 2004-09-06 17:51:47 -0700, "Trevor" said:


wrote in message ...
It gets worse at higher speeds. Here's a table for the same
bike on a 17% grade, where it reaches 70.1 mph and needs 204
rpm to engage a 2124 mm 700c tire with 54 x 12 gearing:

mph rpm watts
70.1 0 0 coasting, not pedalling
62.6 204 0.1 coasting, but pedalling w/no power
70.1 204 1046 pedalling 52 x 12 gear


I think it was E. Merckx whose measured o/p was 1 1/3 hp or
1700Watts
which is 650 watts more than that required for 70mph. High power is
produced at high rpm so a slower cadence is not required.

Merckx might have maxed at 1700 watts (actually, I doubt it), but
that's something he could maintain for 5 seconds. So there's no way
he'd be doing that on a descent.

Also, 204 RPM is ridiculous... nobody is going to sustain that sort of
cadence for more than a few seconds. Certainly you won't be making
good power at that RPM (of course, these days you'd use a 53x11
instead
of a 52x12, that's silly gearing if you're going down a big downhill
fast, welcome to the 90's).

Not all riders are alike, at what speed would 1700watts attain on a
1in10
grade with this calculator. Use 53x12 700x25C 167.5 cranks, flat
back.

Not physically possible, even for Merckx. Because, recall, to go that
70.1 mph you have to do the work of accelerating from 60 mph to 70 mph
by pedaling.

And a 17% grade? Where are you going to find a sustained 17% grade?

Dear Bill,

The closest thing to a sustained 17% grade in Wales appears
to be Bwlch-y-Groes (not the Bwlch Trevor mentioned):

http://www.salite.ch/groes1.htm

There's 2 km of 16% grade at the top. It's much steeper than
any of the 53 other grades in Wales listed at:



http://ciclismo.sitiasp.it/motore.as...484866b8866159
&lingua=eng&da=az

Unfortunately, the site just shows a distance versus
altitude graph, so there's no easy way to tell if turns make
high speed descents impossible..

Trevor, of course, claims to have hit 70 mph on what he
judges to be only a 10% grade, not the 17% that I used for
my example. (Wales is awfully short of 10% grades, judging
by the site above, which doesn't mention the A494 road as
having outstandingly steep sections.)

Trevor eventually remembered a tailwind of less than 10 mph
that was later upgraded to 15 mph.

He also proposes some drafting theories that don't seem to
be exactly air-tight, if you'll pardon the pun.

Riders can reach 70 mph just by coasting, given some
combination of grade, weight, and tailwind.

But Trevor claims to have reached 70 mph routinely by
pedalling a 52 x 12 at 200 rpm on a stretch of Welsh road
whose grade he claims is about 10%.

I'm skeptical, but I think that his 70 mph claim may be a
little more likely than his claim that a sprinting rider was
swerving ten feet from side to side when the gearing
produced only 12.5 feet of forward movement with each stomp
on the pedal.

Or than his claim that any decent sprinter can reach 50 mph
on level ground (Mark McMaster pointed out that the flying
200 meter sprint record is just under ten seconds--only 45.4
mph.)

Or than his claim that both his tires routinely came off the
ground at the same time during sprinting in a sort of
kangaroo-hop tribute to his wheel-building technique, power,
and poor form.

Or than his claim that he has a wheel with spokes worn a
third of the way through where they cross.

Or . . . well, you get the idea.

Carl Fogel

So what's your point Carl? That Trevor is a liar?
Or you enjoy playing Perry Mason to this group?
I think some people really need to get a life here.
Makes me wonder when they have time to actually ride.
If he says he gone 70 mph then so what? He could say he's gone 100 mph
and
I wouldn't even bat an eyelash.
-tom

Dear Tom,

My point is that although 70 mph is quite possible, given
the right combination of grade, weight, tailwind, and
possibly amazing pedalling, an awful lot of claims look
implausible when we ask for details.

Asking for details and pondering the replies is how I learn
more about this sort of thing. Until I pursued the question,
I would have dismissed any claim by Chalo Colina that hecan
easily hit much higher speeds downhill than the rest of us.

But now I know that a bicycle and rider weighing 400 pounds
really can roll down a modest hill at ungodly speeds.

I also have a theory that the Fury RoadMaster rolls down my
daily hill roughly as fast as my touring bike, despite the
handicap of its huge, soggy tires because of its extra mass.

And I've learned why the damn bike always slows down a
little when I start pedalling on the runout from a good
hill, no matter how hard I try to stay tucked in--pedal
motion increases wind drag.

In short, I want to know why I bat an eyelash and whether I
should be raising my eyebrows.

When I first saw Jobst's absurd claim that bicycles stand on
their lower spokes, my eyebrows turned into a handsome
toupee. But after I pondered things and read what other
people said, my eyebrows descended enough for me to scratch
my bald head and eventually admit that Jobst seems to be
right.

Right now, I have one eyebrow lifted about spoke-squeezing
stress-relief claims. Some days, it lowers a little, but on
other days it's joined by the other eyebrow. Right or wrong,
the theory does come from someone with a history of being
right about a lot of bicycling physics.

Whether Trevor is Baron Munchausen on a bicycle or the
victim of unjustified doubts, it's still interesting to look
into his claims.

(The real baron wasn't what the book made him out to be:

http://www.fact-index.com/b/ba/baron_munchhausen.html

See how interesting a little poking around can be?)

IfTrevor has a picture of the wheel with the spokes worn a
third of the way through, then that will be damned
interesting. Wouldn't you click on a link to a picture of
something like that?

Or a picture of a sprinter with both tires coming off the
ground? Or a diagram of how a sprinter can swerve ten feet
sideways as he stomps down on a pedal? Or a link to a site
that explains how to reach 50 mph on a level course? Or a
post from some of Trevor's fellow riders testifying to their
amazing speeds ten years ago in the Welsh countryside?

Unfortunately, a Welsh corgi seems to be thriving on a diet
of Trevor's homework. In the latest example, the wheel with
the badly worn spokes can't be found--which gives Trevor
the opportunity to tell us that this missing wheel with the
worn spokes is also the wheel that proved that Jobst is
utterly wrong.

Possibly the wheel is lying under a piece of the true cross?

Or maybe there really is such a wheel and within a month
we'll have some fascinating pictures of what look like badly
worn spokes. ( I'm wondering whether the galvanized spokes
that Trevor favors might corrode at the crossing and then
erode, something that the stainless-steel-spoke-folk of
rec.bicycles.tech wouldn't be likely to encounter.)

But so far I can't see the cannonball that Trevor rode to
the moon on the A494. Or how he pulled himself past those
riders at 70 mph by his bootstraps. (Read the link above.)

But I do expect that he'll surprise me and that I'll have
fun looking into his future claims. He does seem to have
done a good deal of bicycling, so he might well have some
fascinating points that turn out to be true.

Carl Fogel

Whenever I see Jobst on the road, his usual comments to me is; "Ride Bike!"
My best experience today in learning about bikes is to ride.
I must admit, Jobst saved me a lot of time and money when I started reading
his
technical papers on how to maintain a bicycle in the early years here. I got
more out of his readings then
I have from any other cyclist and I still use a lot of those methods today.
I do read most of his post because I find them worthwhile even though some
are repeats from the past,
how much is there to a bicycle? Other post remind me of a bad neighborhood
and just clutter up the place.
Can you imagine how rich you could be if you had a dime for every bogus post
you've read in this group
-tom

wrote in message
...
On Tue, 7 Sep 2004 13:00:15 -0700, "Tom Nakashima"
wrote:


wrote in message
.. .
On Tue, 7 Sep 2004 10:30:38 -0700, Bill Lloyd
wrote:

On 2004-09-06 17:51:47 -0700, "Trevor" said:


wrote in message ...
It gets worse at higher speeds. Here's a table for the same
bike on a 17% grade, where it reaches 70.1 mph and needs 204
rpm to engage a 2124 mm 700c tire with 54 x 12 gearing:

mph rpm watts
70.1 0 0 coasting, not pedalling
62.6 204 0.1 coasting, but pedalling w/no power
70.1 204 1046 pedalling 52 x 12 gear


I think it was E. Merckx whose measured o/p was 1 1/3 hp or
1700Watts
which is 650 watts more than that required for 70mph. High power is
produced at high rpm so a slower cadence is not required.

Merckx might have maxed at 1700 watts (actually, I doubt it), but
that's something he could maintain for 5 seconds. So there's no way
he'd be doing that on a descent.

Also, 204 RPM is ridiculous... nobody is going to sustain that sort of
cadence for more than a few seconds. Certainly you won't be making
good power at that RPM (of course, these days you'd use a 53x11
instead
of a 52x12, that's silly gearing if you're going down a big downhill
fast, welcome to the 90's).

Not all riders are alike, at what speed would 1700watts attain on a
1in10
grade with this calculator. Use 53x12 700x25C 167.5 cranks, flat
back.

Not physically possible, even for Merckx. Because, recall, to go that
70.1 mph you have to do the work of accelerating from 60 mph to 70 mph
by pedaling.

And a 17% grade? Where are you going to find a sustained 17% grade?

Dear Bill,

The closest thing to a sustained 17% grade in Wales appears
to be Bwlch-y-Groes (not the Bwlch Trevor mentioned):

http://www.salite.ch/groes1.htm

There's 2 km of 16% grade at the top. It's much steeper than
any of the 53 other grades in Wales listed at:



http://ciclismo.sitiasp.it/motore.as...484866b8866159
&lingua=eng&da=az

Unfortunately, the site just shows a distance versus
altitude graph, so there's no easy way to tell if turns make
high speed descents impossible..

Trevor, of course, claims to have hit 70 mph on what he
judges to be only a 10% grade, not the 17% that I used for
my example. (Wales is awfully short of 10% grades, judging
by the site above, which doesn't mention the A494 road as
having outstandingly steep sections.)

Trevor eventually remembered a tailwind of less than 10 mph
that was later upgraded to 15 mph.

He also proposes some drafting theories that don't seem to
be exactly air-tight, if you'll pardon the pun.

Riders can reach 70 mph just by coasting, given some
combination of grade, weight, and tailwind.

But Trevor claims to have reached 70 mph routinely by
pedalling a 52 x 12 at 200 rpm on a stretch of Welsh road
whose grade he claims is about 10%.

I'm skeptical, but I think that his 70 mph claim may be a
little more likely than his claim that a sprinting rider was
swerving ten feet from side to side when the gearing
produced only 12.5 feet of forward movement with each stomp
on the pedal.

Or than his claim that any decent sprinter can reach 50 mph
on level ground (Mark McMaster pointed out that the flying
200 meter sprint record is just under ten seconds--only 45.4
mph.)

Or than his claim that both his tires routinely came off the
ground at the same time during sprinting in a sort of
kangaroo-hop tribute to his wheel-building technique, power,
and poor form.

Or than his claim that he has a wheel with spokes worn a
third of the way through where they cross.

Or . . . well, you get the idea.

Carl Fogel

So what's your point Carl? That Trevor is a liar?
Or you enjoy playing Perry Mason to this group?
I think some people really need to get a life here.
Makes me wonder when they have time to actually ride.
If he says he gone 70 mph then so what? He could say he's gone 100 mph
and
I wouldn't even bat an eyelash.
-tom

Dear Tom,

My point is that although 70 mph is quite possible, given
the right combination of grade, weight, tailwind, and
possibly amazing pedalling, an awful lot of claims look
implausible when we ask for details.

Asking for details and pondering the replies is how I learn
more about this sort of thing. Until I pursued the question,
I would have dismissed any claim by Chalo Colina that hecan
easily hit much higher speeds downhill than the rest of us.

But now I know that a bicycle and rider weighing 400 pounds
really can roll down a modest hill at ungodly speeds.

I also have a theory that the Fury RoadMaster rolls down my
daily hill roughly as fast as my touring bike, despite the
handicap of its huge, soggy tires because of its extra mass.

And I've learned why the damn bike always slows down a
little when I start pedalling on the runout from a good
hill, no matter how hard I try to stay tucked in--pedal
motion increases wind drag.

In short, I want to know why I bat an eyelash and whether I
should be raising my eyebrows.

When I first saw Jobst's absurd claim that bicycles stand on
their lower spokes, my eyebrows turned into a handsome
toupee. But after I pondered things and read what other
people said, my eyebrows descended enough for me to scratch
my bald head and eventually admit that Jobst seems to be
right.

Right now, I have one eyebrow lifted about spoke-squeezing
stress-relief claims. Some days, it lowers a little, but on
other days it's joined by the other eyebrow. Right or wrong,
the theory does come from someone with a history of being
right about a lot of bicycling physics.

Whether Trevor is Baron Munchausen on a bicycle or the
victim of unjustified doubts, it's still interesting to look
into his claims.

(The real baron wasn't what the book made him out to be:

http://www.fact-index.com/b/ba/baron_munchhausen.html

See how interesting a little poking around can be?)

IfTrevor has a picture of the wheel with the spokes worn a
third of the way through, then that will be damned
interesting. Wouldn't you click on a link to a picture of
something like that?

Or a picture of a sprinter with both tires coming off the
ground? Or a diagram of how a sprinter can swerve ten feet
sideways as he stomps down on a pedal? Or a link to a site
that explains how to reach 50 mph on a level course? Or a
post from some of Trevor's fellow riders testifying to their
amazing speeds ten years ago in the Welsh countryside?

Unfortunately, a Welsh corgi seems to be thriving on a diet
of Trevor's homework. In the latest example, the wheel with
the badly worn spokes can't be found--which gives Trevor
the opportunity to tell us that this missing wheel with the
worn spokes is also the wheel that proved that Jobst is
utterly wrong.

Possibly the wheel is lying under a piece of the true cross?

Or maybe there really is such a wheel and within a month
we'll have some fascinating pictures of what look like badly
worn spokes. ( I'm wondering whether the galvanized spokes
that Trevor favors might corrode at the crossing and then
erode, something that the stainless-steel-spoke-folk of
rec.bicycles.tech wouldn't be likely to encounter.)

But so far I can't see the cannonball that Trevor rode to
the moon on the A494. Or how he pulled himself past those
riders at 70 mph by his bootstraps. (Read the link above.)

But I do expect that he'll surprise me and that I'll have
fun looking into his future claims. He does seem to have
done a good deal of bicycling, so he might well have some
fascinating points that turn out to be true.

Carl Fogel

Whenever I see Jobst on the road, his usual comments to me is; "Ride Bike!"
My best experience today in learning about bikes is to ride.
I must admit, Jobst saved me a lot of time and money when I started reading
his
technical papers on how to maintain a bicycle in the early years here. I got
more out of his readings then
I have from any other cyclist and I still use a lot of those methods today.
I do read most of his post because I find them worthwhile even though some
are repeats from the past,
how much is there to a bicycle? Other post remind me of a bad neighborhood
and just clutter up the place.
Can you imagine how rich you could be if you had a dime for every bogus post
you've read in this group
-tom

wrote in message
...
On Tue, 7 Sep 2004 13:00:15 -0700, "Tom Nakashima"
wrote:


wrote in message
.. .
On Tue, 7 Sep 2004 10:30:38 -0700, Bill Lloyd
wrote:

On 2004-09-06 17:51:47 -0700, "Trevor" said:


wrote in message ...
It gets worse at higher speeds. Here's a table for the same
bike on a 17% grade, where it reaches 70.1 mph and needs 204
rpm to engage a 2124 mm 700c tire with 54 x 12 gearing:

mph rpm watts
70.1 0 0 coasting, not pedalling
62.6 204 0.1 coasting, but pedalling w/no power
70.1 204 1046 pedalling 52 x 12 gear


I think it was E. Merckx whose measured o/p was 1 1/3 hp or
1700Watts
which is 650 watts more than that required for 70mph. High power is
produced at high rpm so a slower cadence is not required.

Merckx might have maxed at 1700 watts (actually, I doubt it), but
that's something he could maintain for 5 seconds. So there's no way
he'd be doing that on a descent.

Also, 204 RPM is ridiculous... nobody is going to sustain that sort of
cadence for more than a few seconds. Certainly you won't be making
good power at that RPM (of course, these days you'd use a 53x11
instead
of a 52x12, that's silly gearing if you're going down a big downhill
fast, welcome to the 90's).

Not all riders are alike, at what speed would 1700watts attain on a
1in10
grade with this calculator. Use 53x12 700x25C 167.5 cranks, flat
back.

Not physically possible, even for Merckx. Because, recall, to go that
70.1 mph you have to do the work of accelerating from 60 mph to 70 mph
by pedaling.

And a 17% grade? Where are you going to find a sustained 17% grade?

Dear Bill,

The closest thing to a sustained 17% grade in Wales appears
to be Bwlch-y-Groes (not the Bwlch Trevor mentioned):

http://www.salite.ch/groes1.htm

There's 2 km of 16% grade at the top. It's much steeper than
any of the 53 other grades in Wales listed at:



http://ciclismo.sitiasp.it/motore.as...484866b8866159
&lingua=eng&da=az

Unfortunately, the site just shows a distance versus
altitude graph, so there's no easy way to tell if turns make
high speed descents impossible..

Trevor, of course, claims to have hit 70 mph on what he
judges to be only a 10% grade, not the 17% that I used for
my example. (Wales is awfully short of 10% grades, judging
by the site above, which doesn't mention the A494 road as
having outstandingly steep sections.)

Trevor eventually remembered a tailwind of less than 10 mph
that was later upgraded to 15 mph.

He also proposes some drafting theories that don't seem to
be exactly air-tight, if you'll pardon the pun.

Riders can reach 70 mph just by coasting, given some
combination of grade, weight, and tailwind.

But Trevor claims to have reached 70 mph routinely by
pedalling a 52 x 12 at 200 rpm on a stretch of Welsh road
whose grade he claims is about 10%.

I'm skeptical, but I think that his 70 mph claim may be a
little more likely than his claim that a sprinting rider was
swerving ten feet from side to side when the gearing
produced only 12.5 feet of forward movement with each stomp
on the pedal.

Or than his claim that any decent sprinter can reach 50 mph
on level ground (Mark McMaster pointed out that the flying
200 meter sprint record is just under ten seconds--only 45.4
mph.)

Or than his claim that both his tires routinely came off the
ground at the same time during sprinting in a sort of
kangaroo-hop tribute to his wheel-building technique, power,
and poor form.

Or than his claim that he has a wheel with spokes worn a
third of the way through where they cross.

Or . . . well, you get the idea.

Carl Fogel

So what's your point Carl? That Trevor is a liar?
Or you enjoy playing Perry Mason to this group?
I think some people really need to get a life here.
Makes me wonder when they have time to actually ride.
If he says he gone 70 mph then so what? He could say he's gone 100 mph
and
I wouldn't even bat an eyelash.
-tom

Dear Tom,

My point is that although 70 mph is quite possible, given
the right combination of grade, weight, tailwind, and
possibly amazing pedalling, an awful lot of claims look
implausible when we ask for details.

Asking for details and pondering the replies is how I learn
more about this sort of thing. Until I pursued the question,
I would have dismissed any claim by Chalo Colina that hecan
easily hit much higher speeds downhill than the rest of us.

But now I know that a bicycle and rider weighing 400 pounds
really can roll down a modest hill at ungodly speeds.

I also have a theory that the Fury RoadMaster rolls down my
daily hill roughly as fast as my touring bike, despite the
handicap of its huge, soggy tires because of its extra mass.

And I've learned why the damn bike always slows down a
little when I start pedalling on the runout from a good
hill, no matter how hard I try to stay tucked in--pedal
motion increases wind drag.

In short, I want to know why I bat an eyelash and whether I
should be raising my eyebrows.

When I first saw Jobst's absurd claim that bicycles stand on
their lower spokes, my eyebrows turned into a handsome
toupee. But after I pondered things and read what other
people said, my eyebrows descended enough for me to scratch
my bald head and eventually admit that Jobst seems to be
right.

Right now, I have one eyebrow lifted about spoke-squeezing
stress-relief claims. Some days, it lowers a little, but on
other days it's joined by the other eyebrow. Right or wrong,
the theory does come from someone with a history of being
right about a lot of bicycling physics.

Whether Trevor is Baron Munchausen on a bicycle or the
victim of unjustified doubts, it's still interesting to look
into his claims.

(The real baron wasn't what the book made him out to be:

http://www.fact-index.com/b/ba/baron_munchhausen.html

See how interesting a little poking around can be?)

IfTrevor has a picture of the wheel with the spokes worn a
third of the way through, then that will be damned
interesting. Wouldn't you click on a link to a picture of
something like that?

Or a picture of a sprinter with both tires coming off the
ground? Or a diagram of how a sprinter can swerve ten feet
sideways as he stomps down on a pedal? Or a link to a site
that explains how to reach 50 mph on a level course? Or a
post from some of Trevor's fellow riders testifying to their
amazing speeds ten years ago in the Welsh countryside?

Unfortunately, a Welsh corgi seems to be thriving on a diet
of Trevor's homework. In the latest example, the wheel with
the badly worn spokes can't be found--which gives Trevor
the opportunity to tell us that this missing wheel with the
worn spokes is also the wheel that proved that Jobst is
utterly wrong.

Possibly the wheel is lying under a piece of the true cross?

Or maybe there really is such a wheel and within a month
we'll have some fascinating pictures of what look like badly
worn spokes. ( I'm wondering whether the galvanized spokes
that Trevor favors might corrode at the crossing and then
erode, something that the stainless-steel-spoke-folk of
rec.bicycles.tech wouldn't be likely to encounter.)

But so far I can't see the cannonball that Trevor rode to
the moon on the A494. Or how he pulled himself past those
riders at 70 mph by his bootstraps. (Read the link above.)

But I do expect that he'll surprise me and that I'll have
fun looking into his future claims. He does seem to have
done a good deal of bicycling, so he might well have some
fascinating points that turn out to be true.

Carl Fogel

Whenever I see Jobst on the road, his usual comments to me is; "Ride Bike!"
My best experience today in learning about bikes is to ride.
I must admit, Jobst saved me a lot of time and money when I started reading
his
technical papers on how to maintain a bicycle in the early years here. I got
more out of his readings then
I have from any other cyclist and I still use a lot of those methods today.
I do read most of his post because I find them worthwhile even though some
are repeats from the past,
how much is there to a bicycle? Other post remind me of a bad neighborhood
and just clutter up the place.
Can you imagine how rich you could be if you had a dime for every bogus post
you've read in this group
-tom

Bill Lloyd wrote in
:

And a 17% grade? Where are you going to find a sustained 17%
grade?

Like most of his other claims, in his imagination.

Bill Lloyd wrote in
:

And a 17% grade? Where are you going to find a sustained 17%
grade?

Like most of his other claims, in his imagination.

Bill Lloyd wrote in
:

And a 17% grade? Where are you going to find a sustained 17%
grade?

Like most of his other claims, in his imagination.

Tom Nakashima wrote:

wrote in message
...

...
Trevor, of course, claims to have hit 70 mph on what he
judges to be only a 10% grade, not the 17% that I used for
my example. (Wales is awfully short of 10% grades, judging
by the site above, which doesn't mention the A494 road as
having outstandingly steep sections.)

Trevor eventually remembered a tailwind of less than 10 mph
that was later upgraded to 15 mph.

He also proposes some drafting theories that don't seem to
be exactly air-tight, if you'll pardon the pun.

Riders can reach 70 mph just by coasting, given some
combination of grade, weight, and tailwind.

But Trevor claims to have reached 70 mph routinely by
pedalling a 52 x 12 at 200 rpm on a stretch of Welsh road
whose grade he claims is about 10%.

I'm skeptical, but I think that his 70 mph claim may be a
little more likely than his claim that a sprinting rider was
swerving ten feet from side to side when the gearing
produced only 12.5 feet of forward movement with each stomp
on the pedal.

Or than his claim that any decent sprinter can reach 50 mph
on level ground (Mark McMaster pointed out that the flying
200 meter sprint record is just under ten seconds--only 45.4
mph.)

Or than his claim that both his tires routinely came off the
ground at the same time during sprinting in a sort of
kangaroo-hop tribute to his wheel-building technique, power,
and poor form.

Or than his claim that he has a wheel with spokes worn a
third of the way through where they cross.

Or . . . well, you get the idea.

Carl Fogel


So what's your point Carl? That Trevor is a liar?

At least Mr. Fogel is not accusing Trevor of being a liar on the basis
of what Mr. Fogel thinks are ulterior motives on Trevor's part, but
without Mr. Fogel having any proof of such motives.

--
Tom Sherman

Tom Nakashima wrote:

wrote in message
...

...
Trevor, of course, claims to have hit 70 mph on what he
judges to be only a 10% grade, not the 17% that I used for
my example. (Wales is awfully short of 10% grades, judging
by the site above, which doesn't mention the A494 road as
having outstandingly steep sections.)

Trevor eventually remembered a tailwind of less than 10 mph
that was later upgraded to 15 mph.

He also proposes some drafting theories that don't seem to
be exactly air-tight, if you'll pardon the pun.

Riders can reach 70 mph just by coasting, given some
combination of grade, weight, and tailwind.

But Trevor claims to have reached 70 mph routinely by
pedalling a 52 x 12 at 200 rpm on a stretch of Welsh road
whose grade he claims is about 10%.

I'm skeptical, but I think that his 70 mph claim may be a
little more likely than his claim that a sprinting rider was
swerving ten feet from side to side when the gearing
produced only 12.5 feet of forward movement with each stomp
on the pedal.

Or than his claim that any decent sprinter can reach 50 mph
on level ground (Mark McMaster pointed out that the flying
200 meter sprint record is just under ten seconds--only 45.4
mph.)

Or than his claim that both his tires routinely came off the
ground at the same time during sprinting in a sort of
kangaroo-hop tribute to his wheel-building technique, power,
and poor form.

Or than his claim that he has a wheel with spokes worn a
third of the way through where they cross.

Or . . . well, you get the idea.

Carl Fogel


So what's your point Carl? That Trevor is a liar?

At least Mr. Fogel is not accusing Trevor of being a liar on the basis
of what Mr. Fogel thinks are ulterior motives on Trevor's part, but
without Mr. Fogel having any proof of such motives.

--
Tom Sherman