Recumbents - an alternative?

I was mooching about town with my wife today, chewing the cud and having
a jaw when the subject of HPV's and recumbents came up.

As some of you know I am into EV's, I know that I can build an EV for
local trips but that's no good to me so I have turned my attention to
lightweights and in particular recumbents.

It seems from many of the web pages that most recumbents can reach a
sustainable speed of around 20-25mph. Some websites say much higher
speeds are attainable but not sustainable.

What I need to know is the cadence and gearing of a few recumbents with
the rear wheel sizes logged against the sustainable speed and maximum
speed. The watt output at those speeds would be useful info too if any
of you have got it.

I got permission to buy one next year, it surprised me, I didn't even
ask for per' - and I wasn't going to either! DW just said why don't you
get one next year... I had been thinking of building one and have even
got some plans, freshly downloaded, and a CD on how to start welding.

So any recommendations of type and makes? I figure a boom type with a
shorter wheelbase is best?

Sniper8052

Sniper8052(L96A1) wrote:

What I need to know is the cadence and gearing of a few recumbents with
the rear wheel sizes logged against the sustainable speed and maximum
speed. The watt output at those speeds would be useful info too if any
of you have got it.

my M5 28/20 has yer normal Shimano triple gearing, and a normal 700c
rear wheel. WHen I fit a speedo I'll let you know.

The M5 web site ( http://www.m5-ligfietsen.nl/main.php?sNewLang=GB )
compares expected speed for given power inputs for their different models.

So any recommendations of type and makes? I figure a boom type with a
shorter wheelbase is best?

big fan of 700c rear + 20" front wheel (not that Ive ridden anything
else 20 miles).

Phil

On Sun, 07 Aug 2005 21:51:45 +0000, Sniper8052(L96A1) wrote:

What I need to know is the cadence and gearing of a few recumbents with
the rear wheel sizes logged against the sustainable speed and maximum
speed. The watt output at those speeds would be useful info too if any of
you have got it.

Try this site for power vs speed calculations for many types of upright
and recumbent bikes: http://www.kreuzotter.de/english/espeed.htm

More or less, whatever speed you can sustain in a full-on TT crouch on
an upright you can also do on a high BB recumbent. So for equal wheel
sizes the gearing will be the same.

I could go count the teeth on my Speed Ross, but as I can't do 25mph
without gravity assistance I don't think it's going to help....



Mike

Phil Clarke writes:

Sniper8052(L96A1) wrote:

What I need to know is the cadence and gearing of a few recumbents with
the rear wheel sizes logged against the sustainable speed and maximum
speed. The watt output at those speeds would be useful info too if any
of you have got it.

my M5 28/20 has yer normal Shimano triple gearing, and a normal 700c
rear wheel. WHen I fit a speedo I'll let you know.

The M5 web site ( http://www.m5-ligfietsen.nl/main.php?sNewLang=GB )
compares expected speed for given power inputs for their different models.

So any recommendations of type and makes? I figure a boom type with a
shorter wheelbase is best?

big fan of 700c rear + 20" front wheel (not that Ive ridden anything
else 20 miles).

My 'bent is pretty slow because it is set up as a tourer, and I don't have
plan to fit a speedo to tell me that

For speed think about fairings - or go the Velomobile route, something
like this:
http://www.ligfiets.net/fietsen/type.php3?id=88

Roos

Sniper8052(L96A1) wrote:

It seems from many of the web pages that most recumbents can reach a
sustainable speed of around 20-25mph.

"Some", rather than "most". It's all about aerodynamic improvement, and
while a lowracer has considerably less frontal area than an upwrong
something like an urban compact along the lines of the HPVel Spirit
isn't really any better aerodynamically than a "normal" bike.

You need a 'bent designed for speed to get high sustainable speeds.
Fairings are a large part of the equation too.

So any recommendations of type and makes? I figure a boom type with a
shorter wheelbase is best?

Try everything you can, is the Golden Rule. They differ far more than
uprights and no matter what the paper specs say, if your back doesn't
like the seat it's really just a smart piece of junk.
For high sustained speeds then rule of thumb is lower the better.
Overseat steering tends to be aerodynamic than underseat steering, and
if a tailbox is available (or you're happy you can build one) then that
will push up the speed too.

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

Roos Eisma wrote:

My 'bent is pretty slow because it is set up as a tourer, and I don't have
plan to fit a speedo to tell me that

I tend to find that no matter which one I test ride, they all have
really pathetic engines..

...d

David Martin wrote:
Roos Eisma wrote:


My 'bent is pretty slow because it is set up as a tourer, and I don't have
plan to fit a speedo to tell me that


I tend to find that no matter which one I test ride, they all have
really pathetic engines..


Isn't that because, as Helen found out recently, you use different
muscles/muscles in different ways so that no matter how upwrong fit you
are, you are starting again on a bent?

--
Tony

"I did make a mistake once - I thought I'd made a mistake but I hadn't"
Anon

Tony Raven wrote:
David Martin wrote:
Roos Eisma wrote:


My 'bent is pretty slow because it is set up as a tourer, and I don't have
plan to fit a speedo to tell me that


I tend to find that no matter which one I test ride, they all have
really pathetic engines..


Isn't that because, as Helen found out recently, you use different
muscles/muscles in different ways so that no matter how upwrong fit you
are, you are starting again on a bent?

No, it's because I'm not very upwrong fit, and downright unfit... ANd
far to heavy, and there are too many hills around here. Actually, I'm
only kidding about the hills.

...d

Response to Tony Raven:
Isn't that because, as Helen found out recently, you use different
muscles/muscles in different ways so that no matter how upwrong fit you
are, you are starting again on a bent?

As a mostly-just-commuting cyclist -

On the little uphill on my embarrassingly short commute, I'd hit maybe
15mph on the upright, on a good day. (My commute is short enough to be
treated as a sprint!)

The first time I did it on the trike I struggled to reach 6mph, and had
to have a short rest at the top; my legs felt *just* as if I was
learning to cycle from scratch again - at which point I began to wonder
if I'd just ****ed away a great deal of money. ;-)

After a couple of months of recumbency I'd do the same hill at about
12mph without too much trouble. Don't know my speed now: both my
computers have gone to the great gig in the sky, and I don't bother with
them any more.


--
Mark, UK

"True religion is the life we lead, not the creed we profess."

Tony Raven wrote:

Isn't that because, as Helen found out recently, you use different
muscles/muscles in different ways so that no matter how upwrong fit you
are, you are starting again on a bent?

Not all over again, as the basic cardiovascular transport is at least in
place and it's more a case of tuning up things for a slightly different
mix rather than starting again from scratch. It's not like changing
from a bike to a kayak, for example.

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