Influence of ST< on Top Tube length

[GrantM]

there's a really narrow range of wheelbase, front center and chainstay length measurements that still allow a bike with 700c wheels to handle right. that's the problem with made to measure bikes....most people/bike fitters/portlanders/bikeshop rats/frameforum people drafting'em don't get that part....i think in 90% of cases you're better off trusting the stock geos from the builders that already did their homework and put the wheels in the right place. move the fit around a bit-make sure its not at an extreme and it'll work. rarely does one hear complaints that their pinarello/eddymerckx/even trek madone handled like shit.

there are very few people designing bikes i'd actually trust to design bikes.

jerk

While I agree with your basic point, the devil is in the details.
I suppose it depends what you mean by "narrow"....
My Sachs and my C40 couldn't be more different in geo,
but they both work. Richard would say that the geo of a 53cm Colnago is insane -
bb is too high, chainstays are too short, trail is too high... But it works.

Colnago would says Sachs builds a touring bike, unsuitable for racing.
The differences are not small, like almost 2cm's of chainstay, and 1.5 degrees of head angle. 7mm of rake... 1.2cm of bb ...
So really, it's about how all the stuff works together, not any one part in isolation.

-g

[steve garro]

there's a really narrow range of wheelbase, front center and chainstay length measurements that still allow a bike with 700c wheels to handle right. that's the problem with made to measure bikes....most people/bike fitters/portlanders/bikeshop rats/frameforum people drafting'em don't get that part....i think in 90% of cases you're better off trusting the stock geos from the builders that already did their homework and put the wheels in the right place. move the fit around a bit-make sure its not at an extreme and it'll work. rarely does one hear complaints that their pinarello/eddymerckx/even trek madone handled like shit.

there are very few people designing bikes i'd actually trust to design bikes.

jerk

you're right! the diamond frame is a beautiful thing. it's all been ironed out for the most part. you still get some people that can really be helped by a custom - the short leg - all torso/arm guys, the really tall/short torso gals........but still, as you say, the wheelbase, FC & CS lengths are pretty standard. deviating much beyond the norm will get you something that rides poorly. check this out: http://www.phys.lsu.edu/faculty/gonz...9no9p51_56.pdf steve.

[GrantM]

you're right! the diamond frame is a beautiful thing. it's all been ironed out for the most part.

steve.

I agree that it's been ironed out... but that doesn't mean brands actually
choose to use it... take Cervelo for example: wheelbase varies wildly depending on size
take colnago for example: trail varies wildly depending on size.

You think it's worked out... but here are two big road brands with frucked up geo.

-g

[suspectdevice]

I like to think of seat tube angle as something I manipulate, along with bb drop and chainstay length to get the weight distribution i want for a bike. Thats really most important to me for mtb's, but it sort of applies to road and cross bikes too. Seat angle does more to effect handling than it does fit... except when we talk about getting out of the saddle.

And I will echo what most folks are saying... Some people try to re-invent the bicycle, and that just doesn't work.


:edit: I should mention I am talking about production bikes here, but with custom or production, the only thing I try to think about is putting the rider on the bike in a balanced position... sometimes for production reasons (like the demands of a certain distribuitor), I have to make frames that I don't think handle that well. It's only for the the outlying sizes though...

[Dazza]

sweet! let's ALL start using cubits! steve.

Stevo, you just don't have it yet
I get the client to send their tea cups in
I take a reading from the tea leaves and plot their position
This works well

I get all scientific when the client kills an Owl and stirs the entrails and sends them to me in the post. Fit is then super spot on.

Cheers Dazza

[steve garro]

I agree that it's been ironed out... but that doesn't mean brands actually
choose to use it... take Cervelo for example: wheelbase varies wildly depending on size
take colnago for example: trail varies wildly depending on size.

You think it's worked out... but here are two big road brands with frucked up geo.

-g

let me tell you about it.........i'm building a road bike next for a tiny gal. her current bike has a 76* ST< and a 70.5* HT< x 51mm rake............ghastly, IMO. however, they can bank on the fact that the bike as designed will "fit" a # of the population sufficient enough to make producing it profitable......and it's ridable. is it ideal......well, no.....my geometry changes will fit HER, and while not being groundbreaking in any manner, it will center her on the bike soooo much better. steve.

[steve garro]

Stevo, you just don't have it yet
I get the client to send their tea cups in
I take a reading from the tea leaves and plot their position
This works well

I get all scientific when the client kills an Owl and stirs the entrails and send them to me. Fit is then super spot on.

Cheers Dazza

damn, dazza - i didn't know you guys had owls! steve.

[GrantM]

.....my geometry changes will fit HER, and while not being groundbreaking in any manner, it will center her on the bike soooo much better. steve.

that's why I love you custom guys!

-g

[Dazza]

This is way too big to discuss in detail on any forum
only the basics can be touched
but
The rider's position has to be plotted first
The problems start here, the rider may need to spend an hour a day on core stability work, 500km per week for a couple of years to lean up! {biggest performance gains are getting out of bed when the alarm goes off and hitting the road before you wake up}
Work on pedal force direction {SE efforts}
which effects position and position can affect this
Loosen up their mind {forget equipment shit} and body, weekly hammering on the massage table, lots of strecthing
then they look fitter, feel fitter and are fitter on the bike
then as this is happening
one can nudge, alter, tweak the position.
Then the final position data is arrived at.

A good builder will then put their interpretation of the frame under the rider's position.

Or the punter calls the builder, wants the ego trip of a custom bike and rides once a week for an hour and tells his mates at the coffee shop his custom "Insert name" frame fits him like a glove and he gets more power down on the pedals and it corners on rails and ........

Cheers Dazza
PS. In down under Brisbane, we have Dr Brian Mclean, many years the A.I.S cycling biomechanist, I send my punters to him for the full who ha. But he still cannot make them fitter and leaner!

[Dazza]

damn, dazza - i didn't know you guys had owls! steve.

Yep and all tea leaves and owl entrails are recycled into the compost bin.
For Ginger's herb garden
Cheers Dazza

[Dazza]

this is the technical way to do it

[Dazza]

the foot on the pedal is bloody important
I made a few of these down stairs for Australian Institute of Sport.
One finds the ball and marks it
then with the Llewellyn "Shoe Thingy"one can plot and keep track of any foot position on the pedal to a 01.00mm
Transfer it between shoes as we have the recorded data
and the riders can send the shoes and we fit the cleats
and mail the new shoes back.
But do you think that all the riders, including the Pro riders in Europe take good care of this stuff???
I can tell you stupid horror stories.
Team mechanics are total dick heads with this stuff!!!!!!
I am staying home from the Euro work these days, so I can cut lugs and listen to India flogging the Aussies in test cricket on the radio. :fight:

Cheers Dazza

[ron l edmiston]

many thanks/great education, no longer need my sub's to the bike mag's.

i have housed merlin cyrene, bmc pro mschine, cervelo slc-sl and a dale six13 -----
nothing rides like or fits me like the age 10+ ding/battered richie team cross bike.
found my true kick asser and fun rider!

right fit, steel and lugs for me,
ronnie

[e-RICHIE]

many thanks/great education, no longer need my sub's to the bike mag's.

i have housed merlin cyrene, bmc pro mschine, cervelo slc-sl and a dale six13 -----
nothing rides like or fits me like the age 10+ ding/battered richie team cross bike.
found my true kick asser and fun rider!

right fit, steel and lugs for me,
ronnie

the essence of good fit is economy of word, as well as economy of thought atmo.

[Chance Legstrong]

the foot on the pedal is bloody important
I made a few of these down stairs for Australian Institute of Sport.
One finds the ball and marks it
then with the Llewellyn "Shoe Thingy"one can plot and keep track of any foot position on the pedal to a 01.00mm
Transfer it between shoes as we have the recorded data
and the riders can send the shoes and we fit the cleats
and mail the new shoes back.
But do you think that all the riders, including the Pro riders in Europe take good care of this stuff???
I can tell you stupid horror stories.
Team mechanics are total dick heads with this stuff!!!!!!
I am staying home from the Euro work these days, so I can cut lugs and listen to India flogging the Aussies in test cricket on the radio. :fight:

Cheers Dazza

you kind sir, are going on my list of fucking bad asses!

seriously, thanks for the pics. i am a visual learner (ask my g/f)

[Dazza]

Dazza,

with all due respect any athlete who pedals a bike for a living (or person with functioning nerve endings and a brain) knows when the ball of his/her foot is over the pedal axle. this is not rocket science.

Flux

You would think so eh!
But many do not!
I will not name names
Chaps like McEwen are very good and particular but many
................

[jerk]

Dazza,

with all due respect any athlete who pedals a bike for a living (or person with functioning nerve endings and a brain) knows when the ball of his/her foot is over the pedal axle. this is not rocket science.

Flux

flux-
with all due respect what percentage of athletes who pedal a bike for a living have functioning nerve endings and a brain?

jerk

[jerk]

the essence of good fit is economy of word, as well as economy of thought atmo.

The Industrial Revolution and its consequences have been a disaster
for the human race. They have greatly increased the life-expectancy of
those of us who live in "advanced" countries, but they have
destabilized society, have made life unfulfilling, have subjected
human beings to indignities, have led to widespread psychological
suffering (in the Third World to physical suffering as well) and have
inflicted severe damage on the natural world. The continued
development of technology will worsen the situation. It will certainly
subject human beings to greater indignities and inflict greater damage
on the natural world, it will probably lead to greater social
disruption and psychological suffering, and it may lead to increased
physical suffering even in "advanced" countries.

2. The industrial-technological system may survive or it may break
down. If it survives, it MAY eventually achieve a low level of
physical and psychological suffering, but only after passing through a
long and very painful period of adjustment and only at the cost of
permanently reducing human beings and many other living organisms to
engineered products and mere cogs in the social machine. Furthermore,
if the system survives, the consequences will be inevitable: There is
no way of reforming or modifying the system so as to prevent it from
depriving people of dignity and autonomy.

3. If the system breaks down the consequences will still be very
painful. But the bigger the system grows the more disastrous the
results of its breakdown will be, so if it is to break down it had
best break down sooner rather than later.

4. We therefore advocate a revolution against the industrial system.
This revolution may or may not make use of violence: it may be sudden
or it may be a relatively gradual process spanning a few decades. We
can't predict any of that. But we do outline in a very general way the
measures that those who hate the industrial system should take in
order to prepare the way for a revolution against that form of
society. This is not to be a POLITICAL revolution. Its object will be
to overthrow not governments but the economic and technological basis
of the present society.

5. In this article we give attention to only some of the negative
developments that have grown out of the industrial-technological
system. Other such developments we mention only briefly or ignore
altogether. This does not mean that we regard these other developments
as unimportant. For practical reasons we have to confine our
discussion to areas that have received insufficient public attention
or in which we have something new to say. For example, since there are
well-developed environmental and wilderness movements, we have written
very little about environmental degradation or the destruction of wild
nature, even though we consider these to be highly important.

THE PSYCHOLOGY OF MODERN LEFTISM



6. Almost everyone will agree that we live in a deeply troubled
society. One of the most widespread manifestations of the craziness of
our world is leftism, so a discussion of the psychology of leftism can
serve as an introduction to the discussion of the problems of modern
society in general.

7. But what is leftism? During the first half of the 20th century
leftism could have been practically identified with socialism. Today
the movement is fragmented and it is not clear who can properly be
called a leftist. When we speak of leftists in this article we have in
mind mainly socialists, collectivists, "politically correct" types,
feminists, gay and disability activists, animal rights activists and
the like. But not everyone who is associated with one of these
movements is a leftist. What we are trying to get at in discussing
leftism is not so much a movement or an ideology as a psychological
type, or rather a collection of related types. Thus, what we mean by
"leftism" will emerge more clearly in the course of our discussion of
leftist psychology (Also, see paragraphs 227-230.)

8. Even so, our conception of leftism will remain a good deal less
clear than we would wish, but there doesn't seem to be any remedy for
this. All we are trying to do is indicate in a rough and approximate
way the two psychological tendencies that we believe are the main
driving force of modern leftism. We by no means claim to be telling
the WHOLE truth about leftist psychology. Also, our discussion is
meant to apply to modern leftism only. We leave open the question of
the extent to which our discussion could be applied to the leftists of
the 19th and early 20th century.

9. The two psychological tendencies that underlie modern leftism we
call "feelings of inferiority" and "oversocialization." Feelings of
inferiority are characteristic of modern leftism as a whole, while
oversocialization is characteristic only of a certain segment of
modern leftism; but this segment is highly influential.

FEELINGS OF INFERIORITY

[e-RICHIE]

flux-
with all due respect what percentage of athletes who pedal a bike for a living have functioning nerve endings and a brain?

jerk

i think we need a device to measure the black devices disguised on those
bibshorts atmo. i wouldn't wanna get poked in the chin with one of those.

[jerk]

i think we need a device to measure the black devices disguised on those
bibshorts atmo. i wouldn't wanna get poked in the chin with one of those.

i got this one on a sex tour of new zealand.

you wanna borrow it?

jerk