Wurfitt?

dkahn400 said:

Doki said:

I'd get a raleigh 20 from the tip rather than ride that piece of [censored].

Absolutely.

Me too. Well, actually I got a Dawes Kingpin from the tip, but it's close
enough, and the seatpost extension I made did come from a (not-folding)
Raleigh 20 from the same tip.

In article <[email hidden]>, Peter Clinch <[email hidden]> writes:
|> Membrane wrote:
|>
|> > I agree (read back a few messages), except I can't stand suspension on a
|> > bike that is used on the road.
|>
|> Typically the case that people complaining about suspension on the road
|> have never used suspension properly designed and implemented
|> specifically *for* the road. In such cases the machines are not only
|> more comfortable but more efficient over rougher roads, and cornering at
|> speed on potholed ruins masquerading as back-roads is rather less
|> "interesting" in a Good Way.
|> Perhaps try a Moulton, Birdy, or Streetmachine and see what you think of
|> it then.

Peter Clinch said:

Quoted message said:

I agree (read back a few messages), except I can't stand suspension on a
bike that is used on the road.

Typically the case that people complaining about suspension on the road
have never used suspension properly designed and implemented
specifically *for* the road.

I plead guilty to that.

Quoted message said:

Perhaps try a Moulton, Birdy, or Streetmachine

Two folders and a recumbent suggests that quality suspension on a
"normal" bike built for on-road use is rare.

--
Membrane

Membrane said:

Two folders and a recumbent suggests that quality suspension on a
"normal" bike built for on-road use is rare.

It is indeed, but that doesn't mean it's not worth having. Had Raleigh
not gone out of their way to kill off Moulton production in the 60s who
knows where we might be now...

(Moultons aren't folders, btw)

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 hidden] http://www.dundee.ac.uk/~pjclinch/

Peter Clinch said:

Quoted message said:

Two folders and a recumbent suggests that quality suspension on a
"normal" bike built for on-road use is rare.

It is indeed, but that doesn't mean it's not worth having.

I'd be somewhat suspicious that the bikes that do have quality
suspension have small wheel(s). To me that suggest that the suspension
is there because of the reduced ability of small wheels to cope with
uneven road surfaces.

--
Membrane

In article <[email hidden]>,
Membrane <[email hidden]> writes:
|> Peter Clinch <[email hidden]> wrote:
|>
|> >> Two folders and a recumbent suggests that quality suspension on a
|> >> "normal" bike built for on-road use is rare.
|> >
|> >It is indeed, but that doesn't mean it's not worth having.
|>
|> I'd be somewhat suspicious that the bikes that do have quality
|> suspension have small wheel(s). To me that suggest that the suspension
|> is there because of the reduced ability of small wheels to cope with
|> uneven road surfaces.

Or try the converse but equivalent phrasing: if you don't have decent
suspension, you need large wheels to cope with uneven road surfaces.

Regards,
Nick Maclaren.

Membrane said:

I'd be somewhat suspicious that the bikes that do have quality
suspension have small wheel(s). To me that suggest that the suspension
is there because of the reduced ability of small wheels to cope with
uneven road surfaces.

A bit like saying the reason you have oversized wheels on a "normal"
bike is because the inadequate suspension prevents optimum use of
stronger, more aerodynamic and conveniently sized wheels...

Suspension allows inherent advantages of small wheels to be better
utilised. It's not there as a kludge to get you around smaller wheels,
it's the /combination/ of small wheels and suspension give the whole
thing inherent advantages. You can reasonably state that simplicity,
easier and cheaper production and fewer moving parts is an advantage of
big wheels/rigid bike, but that doesn't make them clearly and
universally a better solution.

Ever notice how cars use suspension and small wheels rather than big wheels?

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 hidden] http://www.dundee.ac.uk/~pjclinch/

Peter Clinch said:

Suspension allows inherent advantages of small wheels to be better
utilised. It's not there as a kludge to get you around smaller wheels,
it's the /combination/ of small wheels and suspension give the whole
thing inherent advantages.

That's an interesting position. Personally I have no problem with the
size of 700 size wheels for storage or similar reasons, I also have no
problem with the strength of 700 wheels. Based on nothing more than
instinct I doubt if smaller wheels would offer a noticeable aerodynamic
advantage on a bike designed for a conventional riding position.

--
Membrane

(Nick Maclaren) said:

|> I'd be somewhat suspicious that the bikes that do have quality
|> suspension have small wheel(s). To me that suggest that the suspension
|> is there because of the reduced ability of small wheels to cope with
|> uneven road surfaces.

Or try the converse but equivalent phrasing: if you don't have decent
suspension, you need large wheels to cope with uneven road surfaces.

Fair point in principle. I favour the KISS principle for engineering
solutions, unless there is an advantage to using small wheels and
suspension that would apply to bikes designed for on-road usage with a
conventional riding position.

--
Membrane

Membrane said:

That's an interesting position. Personally I have no problem with the
size of 700 size wheels for storage or similar reasons, I also have no
problem with the strength of 700 wheels.

Well no, because they've been engineered to be strong enough, but you
could have the same strength with less engineering if they were smaller.
You may not have storage problems, but some people do, and small
wheelers are easier to manhandle too. Ever see a very short person on a
700c bike? It really doesn't work very well. The converse, however, is
not true.

Quoted message said:

Based on nothing more than
instinct I doubt if smaller wheels would offer a noticeable aerodynamic
advantage on a bike designed for a conventional riding position.

But the UCI have still banned them... why should they do such a thing if
they didn't help? Small wheelers /were/ raced with success before they
were banned.

The basic problem with small wheels is FUD. There's an enormous number
of people who assume a small wheeler must be slow and hard to ride up
hills. It's as if they'd never heard of gearing...

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 hidden] http://www.dundee.ac.uk/~pjclinch/

Membrane said:

Based on nothing more than
instinct I doubt if smaller wheels would offer a noticeable aerodynamic
advantage on a bike designed for a conventional riding position.

You should try one!

A drawback off small wheeled frames is that removing the wheels doesn't
make them much smaller, in fact they will be bigger than a conventional
frame.

No amount of suspension will hide the fact that one you've found a hole
which will swallow half a wheel (much easier done with a 17" than with a
700C) you're in trouble

And yes, decent road suspension and big wheels really works

--
---
Marten Gerritsen

INFOapestaartjeM-GINEERINGpuntNL
www.m-gineering.nl

In article <[email hidden]>,
Peter Clinch <[email hidden]> writes:
|> Membrane wrote:
|>
|> > Based on nothing more than
|> > instinct I doubt if smaller wheels would offer a noticeable aerodynamic
|> > advantage on a bike designed for a conventional riding position.
|>
|> But the UCI have still banned them... why should they do such a thing if
|> they didn't help? Small wheelers /were/ raced with success before they
|> were banned.

They don't like competition from better designs? That is why they
banned so many other features.

If I recall, the aerodynamic gain IS significant - not least because
the loss from a square inch of wheel is double relative to that of a
square inch other components.

|> The basic problem with small wheels is FUD. There's an enormous number
|> of people who assume a small wheeler must be slow and hard to ride up
|> hills. It's as if they'd never heard of gearing...

Not entirely. They have a higher rolling resistance, which is only
partially counteracted by suspension. But the hill-climbing claims
are, as you say, unmitigated [censored].

Regards,
Nick Maclaren.

Membrane said:

Fair point in principle. I favour the KISS principle for engineering
solutions, unless there is an advantage to using small wheels and
suspension that would apply to bikes designed for on-road usage with a
conventional riding position.

More efficient over rough surfaces: the relative ease with which a big
wheel rolls over a bump compared to a small one does not mean you don't
have to move the whole bike and rider up over that bump. With
suspension, the only thing that has to move up is the wheel and unsprung
support.

Plus much greater ease of designing a one-size fits most. Do you see
cars coming in different frame sizes to suit different drivers, or worry
you can't borrow your pal's car because it's too big for you?

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 hidden] http://www.dundee.ac.uk/~pjclinch/

Nick Maclaren said:

Not entirely. They have a higher rolling resistance, which is only
partially counteracted by suspension.

It depends on the surface. Over a crappy road a suspended small wheel
works better (been there, done that), on a smooth road the big wheel
works better (been there and done that too). Overall balance is... hard
to call, especially if you're using good high pressure tyres.

The extra friction at the hub from more rotations per unit distance is a
bit of a non-issue with any halfway decent bearings AFAICT.

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 hidden] http://www.dundee.ac.uk/~pjclinch/

In article <[email hidden]>,
Peter Clinch <[email hidden]> writes:
|>
|> > Not entirely. They have a higher rolling resistance, which is only
|> > partially counteracted by suspension.
|>
|> It depends on the surface. Over a crappy road a suspended small wheel
|> works better (been there, done that), on a smooth road the big wheel
|> works better (been there and done that too). Overall balance is... hard
|> to call, especially if you're using good high pressure tyres.

Ah, but a suspended big wheel would do better still :-)

The fact is that, for the same suspension and tyres, a small wheel
has more rolling resistance than a big one. The poor surface is the
circumstance under which I found that wider tyres rolled more efficiently
than narrow ones.

Between an unsuspended big wheel and a suspended small wheel, your
summary seems fair.

Regards,
Nick Maclaren.

Doki said:

"Martin Bulmer" <[email hidden]> wrote in message

news:[email hidden]...

Quoted message said:

I dread to ask, really, but does anyone know anything about these things?

.......at 18Kg it weighs 40lbs in real money ( they probably don't
include some of the gear when they weigh it, like the
wheels,gears,saddle LOL). Grunt!
Robert

Membrane wrote on 11/05/2007 08:18 +0100:

Quoted message said:

Tony Raven said:

The aluminium frame on my road bike has a lifetime guarantee.

It is good to learn that there are now aluminum frames that have such a
warranty, I presume that this is a light weight high end frame.

I bought it eight year ago. So _now_ is not the right word.

Quoted message said:

Quoted message said:

Plus in
the EFBe fatigue test of bicycle frames, half the aluminium frames and
half the carbon frames tested survived the complete test cycle. None of
the steel ones did.
http://www.damonrinard.com/EFBe/frame_fatigue_test.htm

That test deals with high end light weight frames, it should not be used
as an argument against steel frames in general.

No but neither does is support your implication that aluminium frames
are short lived and break easily.

--
Tony

"The most savage controversies are those about matters as to which there
is no good evidence either way."
- Bertrand Russell

Peter Clinch wrote on 11/05/2007 12:29 +0100:

Quoted message said:

I don't have the pressing sense of
urgency, I very much like my comfy seat and full suspension and
built-to-last tank engineering. YMMV.

Are we talking about you or your bike here? ;-)

--
Tony

"The most savage controversies are those about matters as to which there
is no good evidence either way."
- Bertrand Russell

in message <[email hidden]>, Membrane

(') said:

I'm not defending the bike under discussion, but another way to typify a
steel frame is to say that it is the material that is most reliable,
affordable, durable and covered by the longest warranty.

Unfortunately, however, none of those things are true. There are many
grades of steel. The best (for bike frame purposes) are exceedingly good
(for bike frame purposes). The worst, specifically including 'hi-ten', are
very, very bad. Not strong, not durable, and, most especially, not light.

Quoted message said:

The steel frame
of my roadster is covered by a 20 year guarantee, the same frame made
out of aluminum by the same (renowned) manufacturer is covered by a mere
2 year warranty. Again not everyone benefits from the weight saved by an
aluminum frame.

Cheap aluminium frames are lighter (and stronger, and more durable) than
cheap steel ones. Good aluminium frames are often guaranteed for the life
of the first purchaser (my aluminium bike is, for example). But 'carbon
fibre' (in the sense of advanced composites generally) is better (for bike
frame purposes) than aluminium, and, over the next few years, will
probably come to be cheaper than aluminium.

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

;; this is not a .sig

Simon Brooke wrote on 11/05/2007 17:06 +0100:

Quoted message said:

Cheap aluminium frames are lighter (and stronger, and more durable) than
cheap steel ones. Good aluminium frames are often guaranteed for the life
of the first purchaser (my aluminium bike is, for example). But 'carbon
fibre' (in the sense of advanced composites generally) is better (for bike
frame purposes) than aluminium, and, over the next few years, will
probably come to be cheaper than aluminium.

The main problem with composites is that while both steel and aluminium
will take a ding and still be perfectly usable, similar damage to carbon
fibre can be terminal for the frame.

--
Tony

"The most savage controversies are those about matters as to which there
is no good evidence either way."
- Bertrand Russell