Finding a bike that fits.

[Alistair Gunn]

Ben C twisted the electrons to say:
> Isn't it just because they're heavier?

At this point we really need someone who rides a Challenge Fujin SL2 to
reveal how well their ~8.6kg recumbent climbs ...
--
These opinions might not even be mine ...
Let alone connected with my employer ...

 

[Peter Clinch]

Nick Maclaren wrote:

> The question is, however, whether you waste much energy doing so.
> I beleieve that many people don't, but have no evidence for that.

If you move your body up and down with every turn of the pedals hen
that's energy you don't need to be burning that could go into propelling
the bike.

> Well, actually, you DON'T need to maximise your oxygen intake; at
> most, you need to maximise your carbon dioxide output!

All part of breathing though.

> I believe that the panting is merely a symptom of the imbalance, caused
> by the high carbon dioxide content of the blood, and the real recovery
> is being done by the liver. There are lots of such effects. That is
> supported by the fact that some people lie down, others go down on all
> fours, and so on - I think that the crouch you mention is merely a
> convenient resting position and doesn't optimise anything.

I didn't mean to suggest a crouch was best, just that if standing up
straight is really the best thing for the job in hand then everyone
would be standing up straight. There are other factors than the
breathing, quite possibly, but of course the same is true of riding a bike.

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net [email protected] http://www.dundee.ac.uk/~pjclinch/

 

[Peter Clinch]

[email protected] wrote:
> Peter Clinch wrote:
>>> To allow the rider to stand on the pedals to generate more
>>> power on hills, the rider must be over the pedals.
>> You state this as a "requirement", though it clearly isn't
>> if you've got appropriate gearing. I /very/ rarely stand
>> on my pedals.
>
> If going fast uphill is not the most important requirement
> for you, then recumbents are a good design compromise for
> you. There's no need to pretend that they are good at
> everything. (Just as there's no need for Simon to pretend
> that racing designs are good at everything).

I didn't mention recumbents there, I very rarely stand on my pedals on
my *uprights* because I find I get up hills better by spinning lower
gears at high cadence rather than by honking. Since it's a feature of
uprights I don't use, I conclude it's not a "requirement".

> It clearly isn't a perfect substitute, or why are recumbents
> so slow going uphill?

I think you should have a look at the video on the Lightning website of
an R84 cruising past lots of roadies on a climb... They are generally
slow/er/ uphill because they are generally heavier. (links from
http://www.lightningbikes.com/r84.htm)

> Standing on the pedals allows you to
> recruit other muscle groups (shoulders, lower back, hips) to
> help propel you; pushing against the seat doesn't allow
> that, or at least not to the same extent.

Red herring, at least for aerobic work, because the legs can happily use
all the aerobic capacity by themselves. This is why nobody has ever
bothered much with designs for using other than legs as a significant
part of the transmission load, including the fastest designs used in
200m sprints at HPV events.

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net [email protected] http://www.dundee.ac.uk/~pjclinch/

 

[Mike Causer]

On Thu, 28 Sep 2006 04:43:46 -0700, gareth.rees wrote:


> It clearly isn't a perfect substitute, or why are recumbents so slow going
> uphill?

Why do you think recumbents are slower uphill? I find that mine
climbs at the same speed that my lightest upright does on the same hill.


> Standing on the pedals allows you to recruit other muscle groups
> (shoulders, lower back, hips) to help propel you;

This would be useful on long hills to give some muscles a bit of a break,
but in the southern half of the contry there aren't any that long.


Mike

 

[Nick Maclaren]

In article <[email protected]>,
Peter Clinch <[email protected]> writes:
|>
|> If you move your body up and down with every turn of the pedals hen
|> that's energy you don't need to be burning that could go into propelling
|> the bike.

Yes, but why should you do that? Seriously. With a bit of practice,
you can keep your body largely still and just move your legs. Runners
do, after all

|> I didn't mean to suggest a crouch was best, just that if standing up
|> straight is really the best thing for the job in hand then everyone
|> would be standing up straight. There are other factors than the
|> breathing, quite possibly, but of course the same is true of riding a bike.

Er, no. I said that it had the best ERGONOMICS, but almost the worst
ENGINEERING. Relative to crouch or a semi-recumbent, it has 50% more
wind resistance. Relative to a faired full recumbent, it is a good
factor of two, maybe more. And, at a even 14 MPH, wind resistance
accounts for 65% of the energy expended. Never mind if it is 10% or
even 20% more efficient, the other positions win because of that.

And look at the Tour de France when the cyclists are going uphill;
they are all upright. In that case, ergonomic efficiency is more
important than wind resistance, because they are working very hard
but not going very fast.


Regards,
Nick Maclaren.

 

[Peter Clinch]

Nick Maclaren wrote:

> Yes, but why should you do that? Seriously. With a bit of practice,
> you can keep your body largely still and just move your legs. Runners
> do, after all

Because if you're not going to move anything you might as well be sat on
a seat. That's why it's there...

> And look at the Tour de France when the cyclists are going uphill;
> they are all upright.

Up to a point. They're a damn site more crouched over their hoods than
a truly upright position, and if that would make the biggest difference
then that's what they'd do.

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net [email protected] http://www.dundee.ac.uk/~pjclinch/

 

[Ben C]

On 2006-09-28, Nick Maclaren <[email protected]> wrote:
>
> In article <[email protected]>,
> Peter Clinch <[email protected]> writes:
>|>
>|> If you move your body up and down with every turn of the pedals hen
>|> that's energy you don't need to be burning that could go into propelling
>|> the bike.
>
> Yes, but why should you do that? Seriously. With a bit of practice,
> you can keep your body largely still and just move your legs. Runners
> do, after all
>
>|> I didn't mean to suggest a crouch was best, just that if standing up
>|> straight is really the best thing for the job in hand then everyone
>|> would be standing up straight. There are other factors than the
>|> breathing, quite possibly, but of course the same is true of riding a bike.
>
> Er, no. I said that it had the best ERGONOMICS, but almost the worst
> ENGINEERING. Relative to crouch or a semi-recumbent, it has 50% more
> wind resistance. Relative to a faired full recumbent, it is a good
> factor of two, maybe more. And, at a even 14 MPH, wind resistance
> accounts for 65% of the energy expended. Never mind if it is 10% or
> even 20% more efficient, the other positions win because of that.
>
> And look at the Tour de France when the cyclists are going uphill;
> they are all upright. In that case, ergonomic efficiency is more
> important than wind resistance, because they are working very hard
> but not going very fast.

If you mean sitting on the seat, but holding the bars on the top, isn't
there some theory that you can use your back muscles more in that
position? Because they do mostly do a higher torque and lower cadence on
the climbs.

 

[Mark McNeill]

Response to Nick Maclaren:
> With a bit of practice,
> you can keep your body largely still and just move your legs. Runners
> do, after all

No, they don't. That's Irish dancing you're thinking of.


--
Mark, UK
"One of the gigs was in Kidderminster at a venue called Frank Freeman's
Dancing School. This was in the days when groups were called things like
Creedence Clearwater Revival or New Riders of the Purple Sage, and one
of the band said to me: 'Hey, that's a really groovy name.' 'Not
really,' I told him. 'It's a dancing school run by a man named Frank
Freeman'."

 

[Nick Maclaren]

In article <[email protected]>,
Ben C <[email protected]> writes:
|>
|> If you mean sitting on the seat, but holding the bars on the top, isn't
|> there some theory that you can use your back muscles more in that
|> position? Because they do mostly do a higher torque and lower cadence on
|> the climbs.

There is indeed. It is marginally more plausible than Dianetics, but
has no more evidence for it.

If you are fairly strong, you can increase the power output for a
given torque by pulling down on the handlebars. I used to do this
to get up short, steepish hills with a 3-speed. But I generally
rose out of the seat, and used the seat only for sideways bracing
(i.e. like a racing saddle).


Regards,
Nick Maclaren.

 

[David Damerell]

Quoting Peter Clinch <[email protected]>:
>[email protected] wrote:
>>It clearly isn't a perfect substitute, or why are recumbents
>>so slow going uphill?
>I think you should have a look at the video on the Lightning website of
>an R84 cruising past lots of roadies on a climb...

I wonder if that was specially selected in any way?

>They are generally slow/er/ uphill because they are generally heavier.

I don't buy it. There's much more variation in rider weight...
--
David Damerell <[email protected]> Kill the tomato!
Today is First Leicesterday, September.

 

[Rolando]

Rob, I understand about replying to each post separately, and the bit
about putting my response below that to which I am responding, but I
wouldn't know how to use a "proper news client" even if I knew what
that was. As for Outlook Express, I use that for sending and receiving
emails. I used "Groups" because I thought my problem would be seen by a
wider section of the cycling fraternity and therefore more likely to be
successful. As for Google Groups being only a web front-end to Usenet,
I didn't know that, but then, I didn't even know that I didn't know
that, and I STILL don't know, but thanks for trying. You all can now
relax, as I have got myself a folder from Apple bikes in St Annes. It
is by Giant and is called a "Halfway". Despite reports to the contrary,
I CAN touch the ground with my toetips (both at the same time) maybe
because, compared to another folder they had, this one had a seat tube
that sloped backwards to a greater degree. Thanks to all who tried to
help. Ro.
Rob Morley wrote:
> In article <[email protected]>
> Rolando <[email protected]> wrote:
> > My remark regarding function vs fashion wasn't directed at anyone in
> > particular, it was just my perception of the direction that design and
> > manufacturing has taken, with some exceptions. These remarks that I
> > speak of, appear to be directed at you because, just as I am NOT very
> > knowledgable when it comes to bicycle design and terminology, neither
> > am I a dab hand at knowing which button to click. I put my responses to
> > comments from several different contributors into my list of points to
> > reply to, and when I get to last one with something relevant to my
> > original point, that is when I click on "reply". It saves replying to
> > each and every contribution seperately.
>
> It's normal to reply to each post separately, and to put the response
> below each point that you're responding to. You'd do better to use a
> proper news client (or even Outlook Express) instead of Google Groups,
> which is only a web front-end to Usenet.

 

[Rolando]

This may my swansong to this particular group, because I have bought a
bike. It is a folder that carries the name Giant Halfway. Despite some
contributors implying that it was nigh on impossible to reach the
ground with both toetips whilst seated on the saddle, I can manage it
on this particular model, maybe because it has a seat post tube that
lays back further from the verticle than another folder that the dealer
had on show which may be nearer the norm. Rob, I think I understand the
tips about replying to each post separately, and to put my response
below each relevant point, thanks for pointing that out to me. I guess
that comes under Group Etiquette, although quite how one is to know
this as newcomer, escapes me. You might be right about me doing better
using a proper news client (if I knew what a news client, proper or
otherwise, was). As for Outlook Express, I know that one, that's what I
use to send and receive emails, has it got other uses? Fancy, Google
Groups being only a web front-end to Usenet, I didn't know that! what's
more, I didn't know I didn't know that, and I still don't know, am I
thick or what? By the way, just to finish, this is the SECOND time I
have typed and sent this response. The first time, after checking for
spelling mistakes and other errors, I clicked on "post message",
whereupong the page changed to one telling me my message would appear
shortly, but when I checked some time later, it had not appeared. I
checked from my first posting - about finding a bike that fits - to the
end -but nothing, so here goes. Best wishes to all, Ro.
Rob Morley wrote:
> In article <[email protected]>
> Rolando <[email protected]> wrote:
> > My remark regarding function vs fashion wasn't directed at anyone in
> > particular, it was just my perception of the direction that design and
> > manufacturing has taken, with some exceptions. These remarks that I
> > speak of, appear to be directed at you because, just as I am NOT very
> > knowledgable when it comes to bicycle design and terminology, neither
> > am I a dab hand at knowing which button to click. I put my responses to
> > comments from several different contributors into my list of points to
> > reply to, and when I get to last one with something relevant to my
> > original point, that is when I click on "reply". It saves replying to
> > each and every contribution seperately.
>
> It's normal to reply to each post separately, and to put the response
> below each point that you're responding to. You'd do better to use a
> proper news client (or even Outlook Express) instead of Google Groups,
> which is only a web front-end to Usenet.

 

[Simon Brooke]

We've been discussing ergonomics and comfort and balance in a couple of
threads lately, or which this is one. Riding home from a meeting in town
this afternoon (actually a Tour of Britain debrief) I was pondering about
this, and tried a few experiments[1].

The first one just came on me naturally; I was descending a gradient in a
relaxed tuck as one does, **** out of the saddle, feet at quarter to three
and hands resting lightly on the drops. OK, I thought, as one does, what
happens if I take my hands off the bars completely...

Answer: nothing.

Obviously one needs to occasionally touch the saddle or the bars to prevent
oneself rotating around the bottom bracket bearing, but surprisingly
infrequently and not for any length of time. The bike was stable and
tracked perfectly straight with me standing on the pedals and (most of the
time) not touching it anywhere else at all. This was my old road bike - a
steel Raleigh Record Sprint of about thirteen years' vintage.

So soon enough I was off the hill and onto the flat. Is it possible to
pedal without touching the bike anywhere else? Answer, for me, not quite,
but remarkably nearly.

But the real shocker was the next experiment.

I've said before, upthread somewhere, that my balance is appalling. I
cannot track-stand at all, and I cannot stand on one leg with my eyes
closed for three seconds. So, I thought, intrigued, can I ride a bike with
my eyes closed?

Answer: yes.

In practice I didn't ride for more than about ten seconds with my eyes
closed for fear of wandering off the road, but I didn't have any sensation
of being out of control or losing my balance. I was even able to ride no
hands with my eyes closed. I'm fairly confident that if I had someone
riding alongside calling 'left a bit... right a bit' at appropriate
moments, I could ride blindfold indefinitely.

Now, OK, the Raleigh is an old friend and I'm extremely familiar with it,
but it's nothing like as stable as an old rigid mountain bike or a
roadster. But this is just another illustration of the fact that dynamic
balance on a bicycle is a completely different thing from static balance.
I won't disagree that it's a learned skill...

But, back to the point. What I was really trying to think about before I
got sidetracked onto balance, is what proportion of your weight goes into
the different contact points? For me, on any of my bikes, it's
overwhelmingly my legs which take the weight. I would guess that except
when sprinting or climbing out of the saddle, the weight on my wrists
never reaches 200 grammes, and although the maximum weight on the saddle
is more it can't ever be as much as 10% of my weight. It would
be /extremely/ interesting to instrument a bike with strain gauges to
measure this, for a range of riders.

Trying to understand how this posture and its ergonomics work, stand with
your knees bent slightly and just flop forward at the waist, relaxing your
torso completely and letting your arms dangle. This is sort of
the 'ape-man' posture from Victorian human evolution drawings. The weight
of your torso is supported by the muscles of your buttocks and lower back.
There's no weight on your seat, since you're not sitting on anything;
there's no weight on your hands, because they're dangling. The weight is
precisely on the balls of your feet.

For me, this is a very relaxed position. I'm not sure to what extent it's a
very relaxed position as a result of being a cyclist. I'm not sure to what
extent years of cycling have strengthened my back muscles to make it
possible. I'd hazard a bet that all the people who report they are
comfortable on a racing bike will feel comfortable and relaxed in this
posture, and that all the people who aren't will not. But the question is,
why not? What's uncomfortable about it? If it's your lumbar region, then
OK, I understand that. Anything else?

[1] it was about 5.30pm, and thus rush hour, and thus about one car every
ten minutes in these parts out of grockle season.

--
[email protected] (Simon Brooke) http://www.jasmine.org.uk/~simon/

;; When your hammer is C++, everything begins to look like a thumb.

 

[Simon Brooke]

in message <[email protected]>, Rolando
('[email protected]') wrote:

> I'm not wanting to put my feet FLAT on the ground, just my tip-toes.
> Ro.

I can't do both tiptoes at the same time, on any of my bikes. I have rather
small feet, which doesn't help, but it really isn't necessary. And, unlike
many people on this thread, I don't habitually get out of the saddle when
I stop. Just remember to lean the bike towards the foot you've got
unclipped!

--
[email protected] (Simon Brooke) http://www.jasmine.org.uk/~simon/

[ This .sig subject to change without notice ]

 

[[email protected]]

Nick Maclaren wrote:
> > It clearly isn't a perfect substitute, or why are
> > recumbents so slow going uphill? Standing on the pedals
> > allows you to recruit other muscle groups (shoulders,
> > lower back, hips) to help propel you; pushing against
> > the seat doesn't allow that, or at least not to the same
> > extent.
>
> See Whitt and Wilson again. That is another of the
> numerous myths of cycling.

Edition and page?

The third edition ("Bicycling Science: Third Edition", David
Gordon Wilson & Jim Papadopoulos, MIT Press) says (pp. 98-99):

Mechanisms such as rotating hand cranks or rocking
handlebars have been developed to allow the rider to
employ muscles other than the legs for propulsion. But
perhaps surprisingly, this facility is already present to
some degree in conventional upright bicycles: [list of
ways to use arms, torso etc. elided]

Recumbents may be disadvantaged because they do not permit
the rider to use additional muscles in this way.

Which agrees with what I said above.

In the theoretical limit it's true that the additional
muscles do you no good, because you're limited by your
aerobic capacity, which can be easily used up by your legs.
But in the real world the aerobic limit is usually some way
off and a bit of an anaerobic workout can make you go faster
in a sprint or uphill, at least if your cycle and position
permit.

--
Gareth Rees

 

[Peter Clinch]

David Damerell wrote:

> I wonder if that was specially selected in any way?

Of course it is, but there are various RAAM winners etc. quoted on the
site as finding P-38s climb at least as well as wedgies in plenty of
circumstances and they don't have bikes to sell.

>> They are generally slow/er/ uphill because they are generally heavier.
>
> I don't buy it. There's much more variation in rider weight...

On a CTC run once someone asked the leader if 'bents were especially
/good/ at climbing, because I went up the hill on my 20 Kg bike so much
quicker than they could. Nothing to do with it being a recumbent, just
the engine did hills better. If you compare the same rider then the
rider weight (and other characteristics) cancel out and you're left with
the bike, which will /usually/ be heavier if it's a 'bent, and
accordingly slower.

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net [email protected] http://www.dundee.ac.uk/~pjclinch/

 

[Peter Clinch]

[email protected] wrote:

> I think you're getting hung up on my use of the word
> "requirement". I'm using in the engineering sense of a
> measurable need.

Well, you're doing it again! ;-) "Need" means "must have" to me, as
does "require". /Wanting/ something is not *requiring* it, preferences
are wants, not needs, and that's true in an engineering sense or in
simple, plain english. Hence my disagreement!

> Are these 200 m sprints on the level, or are they uphill?
> And are they flying start or standing start?

Level, can be either flying or standing. Record for the flying start is
81 mph, read the accounts of what it took out of the rider and it's a
fair assumption that doing work with something aside from his legs at
the same time would not be on the cards, and of course it wouldn't be
fully aerobic or it would go on for much more than 200m.

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net [email protected] http://www.dundee.ac.uk/~pjclinch/

 

[Peter Clinch]

[email protected] wrote:

> In the theoretical limit it's true that the additional
> muscles do you no good, because you're limited by your
> aerobic capacity, which can be easily used up by your legs.
> But in the real world the aerobic limit is usually some way
> off and a bit of an anaerobic workout can make you go faster
> in a sprint or uphill, at least if your cycle and position
> permit.

However, pulling down on the bars is only useful because gravity isn't
strong enough to give you enough resistance without pulling down. If
you've got an immovable seat that gives you a better basic /pushing/
platform than the gravity you have on an upright allows, so you can get
more out of your legs.

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net [email protected] http://www.dundee.ac.uk/~pjclinch/

 

[Dave Larrington]

Peter Clinch wrote:
> [email protected] wrote:
>
>> In the theoretical limit it's true that the additional
>> muscles do you no good, because you're limited by your
>> aerobic capacity, which can be easily used up by your legs.
>> But in the real world the aerobic limit is usually some way
>> off and a bit of an anaerobic workout can make you go faster
>> in a sprint or uphill, at least if your cycle and position
>> permit.
>
> However, pulling down on the bars is only useful because gravity isn't
> strong enough to give you enough resistance without pulling down. If
> you've got an immovable seat that gives you a better basic /pushing/
> platform than the gravity you have on an upright allows, so you can
> get more out of your legs.

Pulling on the bars is a Bad Thing. Robert Millar says so and he was King
Of The Mountains in the Tour, so ought to know....

--
Dave Larrington
<http://www.legslarry.beerdrinkers.co.uk>
It is impossible to eat a banana without looking like a tw*t.

 

[Peter Clinch]

Rolando wrote:
> This may my swansong to this particular group, because I have bought a
> bike. It is a folder that carries the name Giant Halfway.

Glad you've got something that works for you. You may or may not
have realised that despite your rant-ette about modern
preoccupations with fashion over function, the Halfway is quite a
recent design, so you may need to recant your opinion on everything
new being for show rather than go these days!

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net [email protected] http://www.dundee.ac.uk/~pjclinch/