Funny bikes

email hidden said:

Hi All,

How do 80's funny bikes compare to contemporary TT bikes? To a
contemporary road bike?

I have no firm idea. That won't stop my informed guesses!

Quoted message said:

How much time is the smaller 24" wheel worth? How much is lost with
the bull-horn bars vs aero bars?

The single biggest contribution to TT aero is the rider's position.
The single biggest non-rider contributor is the front wheel, and I
think the head tube may also be an issue.

I think the current wisdom is that all other things being equal, a
funny bike with a small wheel doesn't confer a meaningful aero
advantage. That is, if you built the most aero UCI-legal bike
possible, and then started again with a 24" front wheel, the resulting
bike wouldn't be any more aerodynamic. The frontal area doesn't really
change, because the seat height can't change, which means your body
doesn't get any lower. It's really just a question of what bike parts
actually face the wind.

But everything is not equal: modern deep-section TT wheels will be
more aero than your 80s-vintage small wheel. And the bullhorns will
put your body in a less favorable TT position.

Quoted message said:

An 80's vintage 24" wheel has come into my possession, and I am
considering building a period TT bike around it. With a little coaxing
I can get my old frame back and I have almost all the other stuff too.

And then I'd use it! Find me some of those old Oakleys and I'd be in
business! But would I have any chance in the local ITT's or would it
just be silly?

Your biggest problem might be the local authorities: current UCI TT
bike rules mandate equal-sized wheels, so if the commissaires are
sticklers, you won't get to start.

As for what chance you have, it's mostly about the motor. My feeling
is that the best use of ITTs is to race against yourself, and measure
against what you did on that bike last time.

Hopefully Carl will run a few numbers through one of the bike
computers to tell you how many seconds a good bike versus a bad bike
is likely to cost you in a 10k TT. It's not a lot, but it may be
enough to be the margin of victory, if you're a competitive rider in
the event.

But a funny bike will not be so slow as to be hopeless. in a typical
Cat 4 race, the TT performances are likely to be so widely distributed
that if you're a mid-pack rider on your road bike with no TT bars,
adding a full TT package will make you into a slightly better mid-pack
rider. Do you have some results we could see from previous events?

Quoted post said:

On Dec 19, 1:52 pm, "[email hidden]"

Quoted message said:

Hi All,

Quoted message said:

How do 80's funny bikes compare to contemporary TT bikes? To a
contemporary road bike?

I have no firm idea. That won't stop my informed guesses!

By all means, that's what usenet is for. And informed is no
requirement either!

Quoted message said:

Quoted message said:

How much time is the smaller 24" wheel worth? How much is lost with
the bull-horn bars vs aero bars?

The single biggest contribution to TT aero is the rider's position.
The single biggest non-rider contributor is the front wheel, and I
think the head tube may also be an issue.

I think the current wisdom is that all other things being equal, a
funny bike with a small wheel doesn't confer a meaningful aero
advantage. That is, if you built the most aero UCI-legal bike
possible, and then started again with a 24" front wheel, the resulting
bike wouldn't be any more aerodynamic. The frontal area doesn't really
change, because the seat height can't change, which means your body
doesn't get any lower. It's really just a question of what bike parts
actually face the wind.

But everything is not equal: modern deep-section TT wheels will be
more aero than your 80s-vintage small wheel. And the bullhorns will
put your body in a less favorable TT position.

Quoted message said:

An 80's vintage 24" wheel has come into my possession, and I am
considering building a period TT bike around it. With a little coaxing
I can get my old frame back and I have almost all the other stuff too.

Quoted message said:

And then I'd use it! Find me some of those old Oakleys and I'd be in
business! But would I have any chance in the local ITT's or would it
just be silly?

Your biggest problem might be the local authorities: current UCI TT
bike rules mandate equal-sized wheels, so if the commissaires are
sticklers, you won't get to start.

This would be for club TT's and that sort of thing. Nobody will care
about the UCI rules.

Quoted message said:

As for what chance you have, it's mostly about the motor. My feeling
is that the best use of ITTs is to race against yourself, and measure
against what you did on that bike last time.

I should have been more specific. I meant how I would do comparatively
speaking. I have dreams of winning one day, but I know no amount of
equipment will get me there. I was just wondering if such a bike would
confer any significant advantage over a regular road bike, and I
should consider my results compared to the folks with modern tt bikes,
or if I should stick to comparing to the regular bikes.

Quoted message said:

Hopefully Carl will run a few numbers through one of the bike
computers to tell you how many seconds a good bike versus a bad bike
is likely to cost you in a 10k TT. It's not a lot, but it may be
enough to be the margin of victory, if you're a competitive rider in
the event.

But a funny bike will not be so slow as to be hopeless. in a typical
Cat 4 race, the TT performances are likely to be so widely distributed
that if you're a mid-pack rider on your road bike with no TT bars,
adding a full TT package will make you into a slightly better mid-pack
rider. Do you have some results we could see from previous events?

My 10km TT time on a road bike at the last TT was 14:56, DFL.

Joseph

[email hidden said:

"]On Dec 19, 1:52 pm, "[email hidden]"

Quoted message said:

Hi All,

How do 80's funny bikes compare to contemporary TT bikes? To a
contemporary road bike?

I have no firm idea. That won't stop my informed guesses!

Quoted message said:

How much time is the smaller 24" wheel worth? How much is lost with
the bull-horn bars vs aero bars?

The single biggest contribution to TT aero is the rider's position.
The single biggest non-rider contributor is the front wheel, and I
think the head tube may also be an issue.

I think the current wisdom is that all other things being equal, a
funny bike with a small wheel doesn't confer a meaningful aero
advantage. That is, if you built the most aero UCI-legal bike
possible, and then started again with a 24" front wheel, the resulting
bike wouldn't be any more aerodynamic. The frontal area doesn't really
change, because the seat height can't change, which means your body
doesn't get any lower. It's really just a question of what bike parts
actually face the wind.

But everything is not equal: modern deep-section TT wheels will be
more aero than your 80s-vintage small wheel. And the bullhorns will
put your body in a less favorable TT position.

Quoted message said:

An 80's vintage 24" wheel has come into my possession, and I am
considering building a period TT bike around it. With a little coaxing
I can get my old frame back and I have almost all the other stuff too.

And then I'd use it! Find me some of those old Oakleys and I'd be in
business! But would I have any chance in the local ITT's or would it
just be silly?

Your biggest problem might be the local authorities: current UCI TT
bike rules mandate equal-sized wheels, so if the commissaires are
sticklers, you won't get to start.

As for what chance you have, it's mostly about the motor. My feeling
is that the best use of ITTs is to race against yourself, and measure
against what you did on that bike last time.

Hopefully Carl will run a few numbers through one of the bike
computers to tell you how many seconds a good bike versus a bad bike
is likely to cost you in a 10k TT. It's not a lot, but it may be
enough to be the margin of victory, if you're a competitive rider in
the event.

But a funny bike will not be so slow as to be hopeless. in a typical
Cat 4 race, the TT performances are likely to be so widely distributed
that if you're a mid-pack rider on your road bike with no TT bars,
adding a full TT package will make you into a slightly better mid-pack
rider. Do you have some results we could see from previous events?

The aerobars obscolessed the funnybikes long before they were legislated out of competition. That is is a less powerfull position, and given the aerobars don't cause the rider to sacrifice as much power or handling control, there was no longer an aero benefit for the funny worth sacrificing the power and control over.