K
Kraig Willett
Guest
"Jim Edgar" <[email protected]> wrote in message news:BADFDFAE.412FD%[email protected]...
> Kraig Willett at [email protected] wrote on 5/7/03 6:47
PM:
> > "Jim Edgar" <[email protected]> wrote in message
> >>
> >> IIRC: The conclusion was that at 30 mph there was a slight difference
in the
> >> wind tunnel (i.e. - TT conditions), but at speeds below that it was
within
> >> the margin of error, no?
> >
> > I am glad the data was available to you so that you could make your own conclusion.
> >
> > My conclusion was not as stated above.
>
> See, now you make me go back and reread the thing. Didn't put it together that you were the author
> of that article until now. At any rate...
>
> You stated "Tunnel director Jorge Martinez claims that the wind tunnel balance will provide force
> data that is accurate to +/-0.05 lbs."
>
> So, if the average axial forces in pounds are TT Alpha Q = .73, Oval Jetstream .71, and Reynolds
> Ouzo Pro .70 under calm conditions, (.67, .62, .61 under crosswind, respectively) as shown in your
> chart, how is that not covered by the margin of error?
>
It is, and there was some reference to this in the text.
>
> Clearly I didn't "RC" as I first stated above and I apologize for
confusing
> the issue with my initial statement.
I think I am still confused as to what you are claiming. I was under the impression that you were
originally claiming the axial forces of the aero forks and the EMS fork were within the measurement
uncertainty.
> But, I'm assuming that the extrapoloation to watts and 40K Times use the average axial force as a
> basis, and times times and wattage outputs listed in the last chart also fall wthin the margin of
> error you list.
>
> Even with the margin of error, there is a demonstratable benefit from the 1996 Kestrel fork, as
> you state.
And this is the only point I am trying to make -> less axial force and same power = more speed. Aero
forks do something, and now we can put a number on the magnitude.
> But, my point is that if he's _not_ in a TT, rather in a dynamic
environment
> shielded by other riders in a moving group, how much difference will it make?
If he's taking pulls he's in the same flow-field as the tunnel or a TT, unless you can convince me
that the guy a bike length and a half behind him is altering the flow around the OP's front fork. In
this non-TT taking a pull situation, IMHO, the OP would be faster.
I agree that while drafting, the effect is less - but all else being equal it is still an
improvement over the non-aero fork. I can't definitively comment on the magnitude in that situation
- anyone else?
--
==================
Kraig Willett www.biketechreview.com
==================
> Kraig Willett at [email protected] wrote on 5/7/03 6:47
PM:
> > "Jim Edgar" <[email protected]> wrote in message
> >>
> >> IIRC: The conclusion was that at 30 mph there was a slight difference
in the
> >> wind tunnel (i.e. - TT conditions), but at speeds below that it was
within
> >> the margin of error, no?
> >
> > I am glad the data was available to you so that you could make your own conclusion.
> >
> > My conclusion was not as stated above.
>
> See, now you make me go back and reread the thing. Didn't put it together that you were the author
> of that article until now. At any rate...
>
> You stated "Tunnel director Jorge Martinez claims that the wind tunnel balance will provide force
> data that is accurate to +/-0.05 lbs."
>
> So, if the average axial forces in pounds are TT Alpha Q = .73, Oval Jetstream .71, and Reynolds
> Ouzo Pro .70 under calm conditions, (.67, .62, .61 under crosswind, respectively) as shown in your
> chart, how is that not covered by the margin of error?
>
It is, and there was some reference to this in the text.
>
> Clearly I didn't "RC" as I first stated above and I apologize for
confusing
> the issue with my initial statement.
I think I am still confused as to what you are claiming. I was under the impression that you were
originally claiming the axial forces of the aero forks and the EMS fork were within the measurement
uncertainty.
> But, I'm assuming that the extrapoloation to watts and 40K Times use the average axial force as a
> basis, and times times and wattage outputs listed in the last chart also fall wthin the margin of
> error you list.
>
> Even with the margin of error, there is a demonstratable benefit from the 1996 Kestrel fork, as
> you state.
And this is the only point I am trying to make -> less axial force and same power = more speed. Aero
forks do something, and now we can put a number on the magnitude.
> But, my point is that if he's _not_ in a TT, rather in a dynamic
environment
> shielded by other riders in a moving group, how much difference will it make?
If he's taking pulls he's in the same flow-field as the tunnel or a TT, unless you can convince me
that the guy a bike length and a half behind him is altering the flow around the OP's front fork. In
this non-TT taking a pull situation, IMHO, the OP would be faster.
I agree that while drafting, the effect is less - but all else being equal it is still an
improvement over the non-aero fork. I can't definitively comment on the magnitude in that situation
- anyone else?
--
==================
Kraig Willett www.biketechreview.com
==================