Bike fit for the comfort/utility/trekking/city-sports bike

BIKE FIT FOR NON-RACERS
A few notes from Andre Jute

We all know bike fit is the first element, right? Without a good fit,
bicycling is a misery, right? Those are statements with which it is
hard to disagree.

But I think there are lot of myths and malpractices that have grown up
around bike fitting, partly because a lot of heritage crap came over
from racing bikes, partly because much biking (virtually the whole
shaveleg roadie division) is a heritage of the ten-speed craze, partly
because bicyclists are such conformists they are easy targets for the
guys who exploit fashion victims.

So what happens if you think hard about how your bike fits? As an
example of what happens if you don't, before I got serious about
bikes, I had twelve years of misery with an unsuitable mountainbike.
As a consequence I cycled as little as possible, as a punishment
routine for my health. Then I discovered Dutch bikes of the comfort/
commuting/utility/trekking/city-sports breed. (I would say touring as
well, but some of the American correspondents to RBT interpret a
touring bike as one with drop handles and skinny tyres. Let's be
clear, I intend to include only bikes with handlebars higher than the
saddle, and with tyres of 35mm or fatter.) At the same time I
discovered mailorder bike components.

So I got more comfortable and started taking real pleasure in cycling
as I made myself ever more comfortable on the bike, a beneficial
circle.

Then I discovered custom bikes made by people who put serious though
into making a bike that fits every single customer without a single
compromise. Now I cycle lots for pleasure because I don't hurt when I
get off the bike; my average ride is nearly three times the length of
my longest ride back in the days of the ill-fitting mountainbike.

AN OFF THE SHELF LBS FIT
There was a time when I thought that in buying a bike off the rack,
the most important measurement was the top tube length, which
determines the back angle when the seat height is adjustable and the
reach too with so many stem lengths and angles available. For a casual
cyclist, or one on a tight budget, that is probably still the best
deal, as long as the correct top tube length for the desired back
angle doesn't make the bike so big that the standover height becomes a
painful consideration in tender part.

Notice that my preferred method will almost always give the customer
who falls between factory sizes the bigger bike. My experience with
the sort of salesman who pushes the smaller size as more nimble is
that he either doesn't ride or stands on tiny feet in tight sneakers;
most of us if we take his advice will be hitting our feet on the wheel
every time we turn the handlebars. The longer wheelbase on the bigger
frame also gives a more restful and more comfortable ride. The guy
with short legs in relation to his torse and arms will still have to
take the smaller size unless the top tube slopes quite a bit.

Notice too that anyone but the roadie starts with an individually
determined best back angle, whereas a roadie starts with the
compulsory "flat back" (which I regard with such contempt that it is
the first inherited "wisdom" I discard). The important considerations
in most cases (except roadies) are to get the handlebars as high as
possible and the back as near vertical as possible. Younger, more
supple and (generally) smaller people might compromise the back angle
a little for greater efficiency.

The frame so selected can then be adapted with seat height and
adjustable stem to give probably 95 of cyclists a ride that will be
better than good enough. I repeat, no amount of effort and cost is too
much in order to get the handlebars higher than the saddle.

Another outworn shibboleth from racing/ten speed lore that has
outlived its time is the disdain with which adjustable stems are
treated.

I say, if the customer needs a steering shaft extension, give it to
him. (More easily done with quill stems, but check out the one BBB
make for aheadset installations. I have several types for various
bikes and they all work a treat, and cost lest than twenty bucks.) Or
pressure the factory to leave steering shafts long and use spacers.

CUSTOM BIKES
A custom utility/commuting/comfort bike, unless it needs to have a
very short wheelbase for some reason, or is intended to traverse rough
roads on a world tour, should start with the height of the bottom
bracket lowered so that the rider can get at least one foot on the
ground while seated.

A lower bottom bracket height of course already makes the wheelbase
longer. But a comfort bike should in any event have a reasonably long
wheelbase because it is a desirable control, comfort and endurance
feature.

The low bottom bracket and the long wheelbase makes for a short
seatpost extension above the junction of seat tube and seatstays,
which reduces the loads on the frame and may cause it to be designed
fractionally lighter, not that it matters overly much to me. (The
obsession with mass in all bicycles regardless of use is another
stupidity imported unexamined from racing practice.)

Next, the wheel base, if not already at the maximum desirable length
for the user's road conditions (we want it neither so short as to make
the bike nervous, nor so long as to make it slow and cumbersome in
traffic) may be extended to allow for the user's shoe size.

On a custom bike, of course, the steerer tube is any length one
orders. One could thus simply fit a straight stem of the length which,
with the curves of an already selected handlebar, will put the riders
hands on the grips when he is seated on the saddle with his back at
the correct angle. Or fit an angled stem of the right overall
extension merely for the aesthetic value of the angle. But a custom
bike is expensive and usually expected to last many years, and
everyone's body develops (a euphemism for "grows older"), so I like
adjustable stems. Those that adjust by a swivel that swings the stem
up or down have both reach and height effects. A toollessly adjustable
stem, as fitted on the higher-priced Gazelle bikes, is an excellent
fitment for a multipurpose bike, and an essential for a multirider
bike.

The low bottom bracket and consequent low seat also makes for long
chainstays, so it is easy to get enough spread for fat tires: I'm
enamoured of the Schwalbe Big Apple Liteskins 60x622mm I have on one
of my bikes. The fat tackies in turn obviate the need for further
suspension, though I do in fact use the Brooks B73 triple spring
leather saddle.

All of that makes for a comfortable, safe, fast bike. None of these
rider fitment procedures preclude fitting the bike out with the best
components.

Offered for discussion.

Andre Jute
Visit Jute on Bicycles at
http://www.audio-talk.co.uk/fiultra/...20CYCLING.html

Andre Jute wrote:
BIKE FIT FOR NON-RACERS

I really can't be bothered with crouching down to go a bit faster - it's
a pain in the neck, literally.

You're right a shorter top tube would help. I'm not so sure about the
lower bottom bracket, as I don't like to worry too much about striking a
pedal when going round a corner.

--
www.slowbicyclemovement.org - enjoy the ride

Jim A wrote:
Andre Jute wrote:
BIKE FIT FOR NON-RACERS

I really can't be bothered with crouching down to go a bit faster - it's
a pain in the neck, literally.

I find 35° from the horizontal to be a good compromise between comfort
and reduced frontal area.

You're right a shorter top tube would help. I'm not so sure about the
lower bottom bracket, as I don't like to worry too much about striking a
pedal when going round a corner.


The BB 45-cm above the ground is plenty of clearance, since the bike
will lose traction on dry pavement before the pedal could strike.

--
Tom Sherman - 42.435731,-83.985007

On Jan 23, 5:01*pm, Tom Sherman °_°
wrote:
Jim A wrote:
Andre Jute wrote:
BIKE FIT FOR NON-RACERS

I really can't be bothered with crouching down to go a bit faster - it's
a pain in the neck, literally.

I find 35° from the horizontal to be a good compromise between comfort
and reduced frontal area.

You're right a shorter top tube would help. *I'm not so sure about the
lower bottom bracket, as I don't like to worry too much about striking a
pedal when going round a corner.

The BB 45-cm above the ground is plenty of clearance, since the bike
will lose traction on dry pavement before the pedal could strike.

Yikes, that's a circus bike -- usual BB height is 10-11 inches on a
road bike, and not 17.5. Is this one of those recumbent jokes? You
need a special emoticon when you are doing recumbent jokes. -- Jay
Beattie.

Jay Beattie wrote:
On Jan 23, 5:01 pm, Tom Sherman °_°
wrote:
Jim A wrote:
Andre Jute wrote:
BIKE FIT FOR NON-RACERS

I really can't be bothered with crouching down to go a bit faster -
it's a pain in the neck, literally.

I find 35° from the horizontal to be a good compromise between
comfort and reduced frontal area.

You're right a shorter top tube would help. I'm not so sure about
the lower bottom bracket, as I don't like to worry too much about
striking a pedal when going round a corner.

The BB 45-cm above the ground is plenty of clearance, since the bike
will lose traction on dry pavement before the pedal could strike.

Yikes, that's a circus bike -- usual BB height is 10-11 inches on a
road bike, and not 17.5. Is this one of those recumbent jokes? You
need a special emoticon when you are doing recumbent jokes. -- Jay
Beattie.

Well, there's this (won't work for text-only readers):

Jay Beattie wrote:
On Jan 23, 5:01 pm, Tom Sherman °_°
wrote:
Jim A wrote:
Andre Jute wrote:
BIKE FIT FOR NON-RACERS
I really can't be bothered with crouching down to go a bit faster - it's
a pain in the neck, literally.
I find 35° from the horizontal to be a good compromise between comfort
and reduced frontal area.

You're right a shorter top tube would help. I'm not so sure about the
lower bottom bracket, as I don't like to worry too much about striking a
pedal when going round a corner.
The BB 45-cm above the ground is plenty of clearance, since the bike
will lose traction on dry pavement before the pedal could strike.

Yikes, that's a circus bike -- usual BB height is 10-11 inches on a
road bike, and not 17.5. Is this one of those recumbent jokes? You
need a special emoticon when you are doing recumbent jokes. -- Jay
Beattie.

Sometimes I forget that some riders like the "horsey" position.

--
Tom Sherman - 42.435731,-83.985007

Op 24-1-2010 11:52, Tom Sherman °_° schreef:
Jay Beattie wrote:
On Jan 23, 5:01 pm, Tom Sherman °_°
wrote:
Jim A wrote:
Andre Jute wrote:
BIKE FIT FOR NON-RACERS
I really can't be bothered with crouching down to go a bit faster -
it's
a pain in the neck, literally.
I find 35° from the horizontal to be a good compromise between comfort
and reduced frontal area.

You're right a shorter top tube would help. I'm not so sure about the
lower bottom bracket, as I don't like to worry too much about
striking a
pedal when going round a corner.
The BB 45-cm above the ground is plenty of clearance, since the bike
will lose traction on dry pavement before the pedal could strike.

Yikes, that's a circus bike -- usual BB height is 10-11 inches on a
road bike, and not 17.5. Is this one of those recumbent jokes? You
need a special emoticon when you are doing recumbent jokes. -- Jay
Beattie.

Sometimes I forget that some riders like the "horsey" position.


Maybe you should look around. The vast majority prefer that position and
with reason.

Lou

Liddell Tommi wrote:
Jim A wrote:
Andre Jute wrote:
BIKE FIT FOR NON-RACERS

I really can't be bothered with crouching down to go a bit faster - it's
a pain in the neck, literally.

I find 35° from the horizontal to be a good compromise between comfort
and reduced frontal area.

You're right a shorter top tube would help. *I'm not so sure about the
lower bottom bracket, as I don't like to worry too much about striking a
pedal when going round a corner.

The BB 45-cm above the ground is plenty of clearance, since the bike
will lose traction on dry pavement before the pedal could strike.

You're in the wrong thread, Liddell Tommi. The thread you want is
"Bikes for Freaks".

In this thread, turn 180 degrees around and look at the smarter
siblings of one of your bikes, the RANS crank forward design.

Andre Jute
Visit Jute on Bicycles at
http://www.audio-talk.co.uk/fiultra/...20CYCLING.html

On Jan 22, 8:39*pm, Jim A wrote:
Andre Jute wrote:
BIKE FIT FOR NON-RACERS

I really can't be bothered with crouching down to go a bit faster - it's
a pain in the neck, literally.

Nothing but a fashion for impressionable.

You're right a shorter top tube would help. *I'm not so sure about the
lower bottom bracket, as I don't like to worry too much about striking a
pedal when going round a corner.

You soon get the rhythm of pedaling so that the low side pedal is up
at highest lean angle.

The thing is that most bikes have too high a bottom bracket, a
practice inherited from mountain bikes, and now enforced on cyclists
by ever-cheapening production practices. Not that it wasn't already a
practice in steelframe days, because not everyone had the skill to
alter the angles on lugs.

--www.slowbicyclemovement.org- enjoy the ride

Andre Jute
The rest is magic hidden in the hub.
For rare hub gear bikes, visit Jute on Bicycles at
http://www.audio-talk.co.uk/fiultra/...20CYCLING.html

Lou Holtman wrote:
Op 24-1-2010 11:52, Tom Sherman °_° schreef:
Jay Beattie wrote:
On Jan 23, 5:01 pm, Tom Sherman °_°
wrote:
Jim A wrote:
Andre Jute wrote:
BIKE FIT FOR NON-RACERS
I really can't be bothered with crouching down to go a bit faster -
it's
a pain in the neck, literally.
I find 35° from the horizontal to be a good compromise between comfort
and reduced frontal area.

You're right a shorter top tube would help. I'm not so sure about the
lower bottom bracket, as I don't like to worry too much about
striking a
pedal when going round a corner.
The BB 45-cm above the ground is plenty of clearance, since the bike
will lose traction on dry pavement before the pedal could strike.

Yikes, that's a circus bike -- usual BB height is 10-11 inches on a
road bike, and not 17.5. Is this one of those recumbent jokes? You
need a special emoticon when you are doing recumbent jokes. -- Jay
Beattie.

Sometimes I forget that some riders like the "horsey" position.


Maybe you should look around. The vast majority prefer that position and
with reason.

Convention forced by the UCI banning recumbents on April 1, 1934 for
being too fast.

In the US, the vast majority prefer a semi-recumbent position inside an
internal combustion powered vehicle.

--
Tom Sherman - 42.435731,-83.985007