Brompton questions

Epetruk said:

However, I have three questions:

1. I notice that braking is a lot less instant than with a regular bike,
i.e. I have to apply more pressure than I would with a regular bike to
brake. I was told that this is because of the smaller wheel diameter - the
point at which the pads press against the rim is rotating with more force
than it would with an ordinary bike. My physics is somewhat flaky, so I'd
appreciate it if someone could corroborate/contradict this.

Smaller rims don't need more force on the brake pads. To stop in the
same distance the amount of rim going through the brake pads is the same
for any size wheel (provided the tyre depth is small compared to the
wheel diameter). It takes a lot more revolutions of a small wheel to
achieve that and the rim will get hotter but the brake force is the same.

FWIW I find my B brakes equally as good as my other caliper brakes

Quoted message said:

2. One thing I love about the bike is its manoeuvrability! It really is so
easy zipping in and out of traffic because of those small wheels. It makes
me wonder - is there a limit to how small the wheels on a bike could be
(assuming the right kind of material(s) could be found)? Perhaps this could
lead to even more compact folders.

The limit is road imperfections. The smaller the wheel the less able it
is to roll over pot holes and obstructions. Folders have been built
with much smaller wheel sizes (down to skate wheel size) but they are
impractical on all but smooth surfaces)

Quoted message said:

3. Is it safe to sit on the seat of the Brompton while it's folded, for
example if you're waiting for a train at the station?

I do although some say it can bend the seat post. Otherwise sit on the
top tube.

--
Tony

"A facility for quotation covers the absence of original thought" Lord
Peter Wimsey (Dorothy L. Sayers)

Epetruk said:

1. I notice that braking is a lot less instant than with a regular bike

Depends a lot on what your regular bike is... The Maguras on the
Streetmachine do a better job, but then they bloody well ought to
at £60 each!
As long as they stop you quite well enough, I wouldn't worry. Mine do.

Quoted message said:

2. One thing I love about the bike is its manoeuvrability! It really is so
easy zipping in and out of traffic because of those small wheels. It makes
me wonder - is there a limit to how small the wheels on a bike could be
(assuming the right kind of material(s) could be found)? Perhaps this could
lead to even more compact folders.

As Tony has ssaid, there are smaller wheel folders out there. The
smallest that could pretend to be practical over anyything other
than smooth tarmac are probably the 12" wheels on the R&M Frog, a
sort of Birdy on a diet. The fact that it has good suspension is a
major factor in it working as well as it does, but suspension can
only do so much if the pothole is basically the same size as the
wheel...

Quoted message said:

3. Is it safe to sit on the seat of the Brompton while it's folded, for
example if you're waiting for a train at the station?

I would think so, but it'd be a bit low. Since it only takes 15
seconds to fold I'm more inclined to leave it up until, oooh, about
15 seconds or so before it needs folded, and just sit on it while
deployed.

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/

--

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

Well, I've been using my Brompton for nearly two months, and I'm still
happy
with it. I even been able to figure out how to change the rear tyre -
something I haven't had to do yet, but which I was worried I would have
problems with.

However, I have three questions:

1. I notice that braking is a lot less instant than with a regular bike,

Hello,
In my own experience after much modification etc I have decided that the
poor braking is due to long outer cable length. Once the outer cable is
fully compressed the braking improves. But it will not be so good as a
conventional bike due to the cables being folded numerous times. To improve
braking try to fold as little as possible! I know this is not what you were
looking for.
John.

Quoted message said: