Why can your feet hit the front tire on some road bikes?

In article ,
"Clive George" wrote:

"Ron Ruff" wrote in message
...
SMS wrote:
You mainly run into this on compact frame road bikes, which should be
avoided for several other reasons as well.

That's odd since a sloping top tube has absolutely nothing to do with
this.

He forgot to mention it's also a feature of Aluminium frames and threadless
steerers...

No idea why Steven would think any such thing. I ride a variety of 50-53
cm road bikes. Let's check the tape...

-1990ish steel Pinarello? I hit my toe against the front wheel
-early 80s Miyata 210 27" wheeled steel tourer? I hit my toe against the
fender, and would be able to hit the wheel if the fender wasn't there.
-Nashbar "X" cyclocross frame? I hit my toe against the front wheel.
-Fetish Cycles sorta-compact (it's hard to tell in the smaller sizes)
racing bike? I . . . can't remember. I think so, though.
-Kona Kilauea hardtail MTB? Hey, no overlap!

In practice, on fenderless bikes I don't find toe overlap worth worrying
about. It's just never caused me any problems and I say that while
admitting that I have done trackstands where my foot hit the front wheel.

On my fendered commuter (the Miyata), I have kicked fenders to death.
That's annoying. Annoying enough that for a time I considered building a
26"-wheeled commuter, which would solve the problem fairly efficiently.

That said, I got over it. I've stopped kicking the fender so much,
mostly because I'm a bit better bike-handler*. If I decide to start
caring about it again, I'll build a 26"-wheeled commuter. As it is, the
Miyata is a nice bike to ride and works well. I'm reluctant to dismiss
it from service.

*Some of my club-mates, having witnessed my more spectacular offs, might
differ.

--
Ryan Cousineau http://www.wiredcola.com/
"In other newsgroups, they killfile trolls."
"In rec.bicycles.racing, we coach them."

On Oct 6, 3:38*pm, "Clive George" wrote:
"Ron Ruff" wrote in message

...

SMS wrote:
You mainly run into this on compact frame road bikes, which should be
avoided for several other reasons as well.

That's odd since a sloping top tube has absolutely nothing to do with
this.

He forgot to mention it's also a feature of Aluminium frames and threadless
steerers...

POTM!!!

Chalo Colina wrote:
[...]
There is very little excuse, in my opinion, for using different
diameter tires on the same bike unless coping with an absurd layout
(recumbents) or exercising artistic prerogative (choppers).[...]

The recumbent design is logical from the perspective of comfort and
reduced frontal area, while choppers have no practical reason to exist.

--
Tom Sherman - 42.435731,-83.985007
If my posts in general annoy or offend, please kill-file.

Clive George wrote:
"Ron Ruff" wrote in message
...
SMS wrote:
You mainly run into this on compact frame road bikes, which should be
avoided for several other reasons as well.
That's odd since a sloping top tube has absolutely nothing to do with
this.

He forgot to mention it's also a feature of Aluminium frames and threadless
steerers...

Not usually, though of course it's unlikely that you'd find a compact
frame steel road bicycle. Those buying steel and titanium road bikes are
purists.

Tom Sherman wrote:
Chalo Colina wrote:
[...]
There is very little excuse, in my opinion, for using different
diameter tires on the same bike unless coping with an absurd layout
(recumbents) or exercising artistic prerogative (choppers).[...]

The recumbent design is logical from the perspective of comfort and
reduced frontal area, while choppers have no practical reason to exist.

Choppers offer superior cooling due to increased frontal area. Their
cool factor is so high, in fact, that there is no range overlap
between the coolest 'bents and the least cool choppers. :^)

Chalo

On Oct 6, 8:47*pm, SMS wrote:
Clive George wrote:
"Ron Ruff" wrote in message
....
SMS wrote:
You mainly run into this on compact frame road bikes, which should be
avoided for several other reasons as well.
That's odd since a sloping top tube has absolutely nothing to do with
this.

He forgot to mention it's also a feature of Aluminium frames and threadless
steerers...

Not usually, though of course it's unlikely that you'd find a compact
frame steel road bicycle. Those buying steel and titanium road bikes are
purists.

Interesting dodge, Steve.

The premise of compact frame geometry is to lower the seat cluster and
slope the top tube, so as to increase standover clearance while
leaving the rest of the geometry intact. How does that affect TCO?

FWIW, my leg:torso ratio is sufficient that I don't find compact
geometry necessary, but for guys with short legs and long arms, it's a
godsend.

On Oct 6, 5:44*pm, Michael Press wrote:
In article
,





*Chalo wrote:
Mike Jacoubowsky wrote:

Chalo wrote:

Davej wrote:

Seems like a design flaw to me but it had to be intentional.

Like so many other details of bike frame design, I attribute this
characteristic to a failure of imagination.

It's the same failure of imagination that puts identical length
chainstays and the same seat angle on a 68cm frame as on a 52cm
frame. *I reckon that most such mistakes are perpetrated by folks who
ride 56-60cm frames themselves.

The distance between your foot and the front tire is determined by many
things-

#1: Length of crank arm
#2: Length of foot
#3: Size of front wheel

The size of the front wheel is an arbitrary value. *The fact that most
manufacturers would rather have shorter riders suffer toe overlap than
use a wheel size appropriate to the rider's size displays... a failure
of imagination.

I am a shorter rider and would never take on a bicycle
with smaller wheels. *Mostly because larger wheels roll
better. My feet overlap the front tire swing, and I don't
care. I execute slow speed maneuvers without incident or bother.

--
Michael Press- Hide quoted text -

- Show quoted text -

So even though a 650C wheeled bike would be better proportioned for
you and have better steering because the head tube angle isn't very
slack to get the front wheel in front of the feet, you would rather
ride a poor handling and poor fitting 700C bike. Logic.

On Oct 6, 7:08*pm, Frank Krygowski wrote:
On Oct 6, 1:49*pm, Chalo wrote:



Terry used an ISO 520 tire for that bike. *That's their problem, and
the problem of their buyers. *If it had been ISO 559 (as you noted) or
even ISO 507, then you'd not have faced such a needless ordeal.
There's also the likelihood that if manufacturers more commonly used
smaller wheels for smaller bikes, then tires in those sizes would be
far less exotic.

I wondered if the reason for the odd 520 sizing was to get narrower
tires. *I don't have a good feel for what widths are available in
different rim diameters. *The bike (a Symmetry) came set up as a
"road," not touring, bike.

There is very little excuse, in my opinion, for using different
diameter tires on the same bike unless coping with an absurd layout
(recumbents) or exercising artistic prerogative (choppers). *If Terry
had been more concerned with chassis dynamics and less with marketing-
driven product distinction, they'd have used ISO 559 at both ends.

I think the reason is partly historical. *IIRC, Terry copied Bill
Boston's idea to use the small front, and like him, kept the 700c rear
because in those days, you needed it to get a reasonably high top
gear.

Now, of course, we're in the era where Shimano makes cassettes capable
of insanely high gears. *So yes, it would be way more sensible to have
equal wheels, whatever the size. *And yes, maybe the unequal wheels
are now just Terry's version of Hetchins "curly stays."

I did a quick look for the "advent" of the 11t cog, to no avail and
someone here knows exactly, anyhow.

Terry started the unequal wheel thing in the mid-late 70's, or early
80's, when 12t cogs were available. Chainrings larger than 52t have
been around a long, long time.

IMHO, the "layout made famous by Terry" was market driven, as in, the
market was not ready for small wheels on the back, too g.
The Terry bikes, at least one end looked normal, and don't forget who
the market was, with a few perhaps mostly self-perceived "image"
problems and other. So, maybe "special" v. "just plain weird" was the
order of the day? Sold a fair number of bikes and no doubt got some
ladies out riding, so good on Georgina there.

650c, both ends, seems to really work, although my experience is
limited to observation of one female 650c rider (plus a few others who
attended much less frequently) who was a fixture on our inner-city
Houston Wed. night group rides ("lots of bad pavement"), and a few
rides with my other half on her new custom Guru before she went back
to running g due to time/work sched. realities.

I don't "know" and as with the "history of cogs" above, if it's
important, someone will fill in the gaps, but it seems that the Tri-
people hashed out the rolling resistance v. lower aero profile thing
IRT 700c/650c wheels and it was a wash (?). I didn't see the (very)
good bike handler woman in Houston having any problems with her tiny
wheels in spite of nasty, debris-filled pavement. On one particular
ride with my wife, we encountered a few miles' worth of swirling,
buffeting winds in a small canyon. She was a newly "returned" rider,
this was a "first few" ride and no problem seen or reported in
response to questioning g. "First bike I've been comfortable on"
which report does include the Terry saddle, the one with the open
middle that some men apparently like, also g.

BTW: The supposedly "woman specific geometry" 700c bikes spec'd in a
few high-end catalogs didn't seem to come close to ideal geometry for
my wife, specifically because of proportionally long top tubes-- !?
women tend to have long legs, shorter upper bodies, no?-- and steep
seat tube angles (not good with a long femur), and that's before you
get to the 71-72deg head tube angles.

IOW, manufacturers are still reacting to the "tiny tires" image
problem? --D-y

In article
,
" wrote:

On Oct 6, 5:44*pm, Michael Press wrote:
In article
,
*Chalo wrote:
Mike Jacoubowsky wrote:

Chalo wrote:

Davej wrote:

Seems like a design flaw to me but it had to be intentional.

Like so many other details of bike frame design, I attribute this
characteristic to a failure of imagination.

It's the same failure of imagination that puts identical length
chainstays and the same seat angle on a 68cm frame as on a 52cm
frame. *I reckon that most such mistakes are perpetrated by folks who
ride 56-60cm frames themselves.

The distance between your foot and the front tire is determined by many
things-

#1: Length of crank arm
#2: Length of foot
#3: Size of front wheel

The size of the front wheel is an arbitrary value. *The fact that most
manufacturers would rather have shorter riders suffer toe overlap than
use a wheel size appropriate to the rider's size displays... a failure
of imagination.

I am a shorter rider and would never take on a bicycle
with smaller wheels. *Mostly because larger wheels roll
better. My feet overlap the front tire swing, and I don't
care. I execute slow speed maneuvers without incident or bother.

So even though a 650C wheeled bike would be better proportioned for
you and have better steering because the head tube angle isn't very
slack to get the front wheel in front of the feet, you would rather
ride a poor handling and poor fitting 700C bike. Logic.

Where do you get the idea the handling is poor?

--
Michael Press

wrote:
On Oct 6, 7:08 pm, Frank Krygowski wrote:
On Oct 6, 1:49 pm, Chalo wrote:



Terry used an ISO 520 tire for that bike. That's their problem, and
the problem of their buyers. If it had been ISO 559 (as you noted) or
even ISO 507, then you'd not have faced such a needless ordeal.
There's also the likelihood that if manufacturers more commonly used
smaller wheels for smaller bikes, then tires in those sizes would be
far less exotic.
I wondered if the reason for the odd 520 sizing was to get narrower
tires. I don't have a good feel for what widths are available in
different rim diameters. The bike (a Symmetry) came set up as a
"road," not touring, bike.

There is very little excuse, in my opinion, for using different
diameter tires on the same bike unless coping with an absurd layout
(recumbents) or exercising artistic prerogative (choppers). If Terry
had been more concerned with chassis dynamics and less with marketing-
driven product distinction, they'd have used ISO 559 at both ends.
I think the reason is partly historical. IIRC, Terry copied Bill
Boston's idea to use the small front, and like him, kept the 700c rear
because in those days, you needed it to get a reasonably high top
gear.

Now, of course, we're in the era where Shimano makes cassettes capable
of insanely high gears. So yes, it would be way more sensible to have
equal wheels, whatever the size. And yes, maybe the unequal wheels
are now just Terry's version of Hetchins "curly stays."

I did a quick look for the "advent" of the 11t cog, to no avail and
someone here knows exactly, anyhow.

Terry started the unequal wheel thing in the mid-late 70's, or early
80's, when 12t cogs were available. Chainrings larger than 52t have
been around a long, long time.

IMHO, the "layout made famous by Terry" was market driven, as in, the
market was not ready for small wheels on the back, too g.
The Terry bikes, at least one end looked normal, and don't forget who
the market was, with a few perhaps mostly self-perceived "image"
problems and other. So, maybe "special" v. "just plain weird" was the
order of the day? Sold a fair number of bikes and no doubt got some
ladies out riding, so good on Georgina there.

650c, both ends, seems to really work, although my experience is
limited to observation of one female 650c rider (plus a few others who
attended much less frequently) who was a fixture on our inner-city
Houston Wed. night group rides ("lots of bad pavement"), and a few
rides with my other half on her new custom Guru before she went back
to running g due to time/work sched. realities.

I don't "know" and as with the "history of cogs" above, if it's
important, someone will fill in the gaps, but it seems that the Tri-
people hashed out the rolling resistance v. lower aero profile thing
IRT 700c/650c wheels and it was a wash (?). I didn't see the (very)
good bike handler woman in Houston having any problems with her tiny
wheels in spite of nasty, debris-filled pavement. On one particular
ride with my wife, we encountered a few miles' worth of swirling,
buffeting winds in a small canyon. She was a newly "returned" rider,
this was a "first few" ride and no problem seen or reported in
response to questioning g. "First bike I've been comfortable on"
which report does include the Terry saddle, the one with the open
middle that some men apparently like, also g.

BTW: The supposedly "woman specific geometry" 700c bikes spec'd in a
few high-end catalogs didn't seem to come close to ideal geometry for
my wife, specifically because of proportionally long top tubes-- !?
women tend to have long legs, shorter upper bodies, no?-- and steep
seat tube angles (not good with a long femur), and that's before you
get to the 71-72deg head tube angles.

IOW, manufacturers are still reacting to the "tiny tires" image
problem? --D-y

11t first popularized on '70s Dura Ace AX six cassette (exotica
notwithstanding)
--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971
** Posted from http://www.teranews.com **