Does drafting help the guy in frount?

On Mon, 12 Apr 2004 17:58:46 -0700, "RWM" may
have said:

As a follow up question, has any reputable research been done to analyze the
effects of having a rider in your draft at different speeds.

I haven't heard of any that involved actual measurements, and I don't
know how you would measure this outside a wind tunnel, which isn't a
real-world setting.

However, by way of a reality check from auto racing:

In my direct experience, having another car drafting me at 50 mph at a
distance of less than two feet when going down a straight makes zero
difference in *my* speed. On a curve at drafting speeds, it's very
hard to say whether it helps, hurts, or has no effect. At 120 to
130mph on a straight, it does make a noticeable difference; I can see
a speed gain of two or three mph (rarely more) as the other driver
smooths the airflow off my rear...but this comes with a potentially
disastrous penalty if something goes wrong. I haven't been involved
in racing at higher speeds in which drafting was a factor. (For that
matter, it's been 20 years since I was last on the track, but the
air's behavior hasn't changed.)

Long-haul truck drivers, whose vehicles have a much greater frontal
area, report that a closely tailgating big rig may boost the speed for
the leader by a mile an hour at highway speeds (70mph), but the risk
involved is considered too great by most. At a more reasonable but
still not really safe following distance, only the drafting truck gets
any benefit.

Extrapolating that back to bikes, I cannot see where a smaller body at
a lower speed has any chance whatsoever of producing the "boost for
the leader" effect. It's just not going to happen.

--
My email address is antispammed; pull WEEDS if replying via e-mail.
Typoes are not a bug, they're a feature.
Words processed in a facility that contains nuts.

"B a r r y" wrote
In my direct experience, having another car drafting me at 50 mph at a
distance of less than two feet when going down a straight makes zero
difference in *my* speed. On a curve at drafting speeds, it's very
hard to say whether it helps, hurts, or has no effect. At 120 to
130mph on a straight, it does make a noticeable difference; I can see
a speed gain of two or three mph (rarely more) as the other driver
smooths the airflow off my rear...but this comes with a potentially
disastrous penalty if something goes wrong. I haven't been involved
in racing at higher speeds in which drafting was a factor. (For that
matter, it's been 20 years since I was last on the track, but the
air's behavior hasn't changed.)

Sure as hell works for the NASCAR guys.

Theo

On Thu, 15 Apr 2004 01:02:05 GMT, B a r r y
may have said:

On Wed, 14 Apr 2004 15:23:05 GMT, Werehatrack
wrote:

At 120 to
130mph on a straight, it does make a noticeable difference; I can see
a speed gain of two or three mph (rarely more) as the other driver
smooths the airflow off my rear...but this comes with a potentially
disastrous penalty if something goes wrong.

Have you ever been "bump drafted"? G

Not twice by the same driver.

--
My email address is antispammed; pull WEEDS if replying via e-mail.
Typoes are not a bug, they're a feature.
Words processed in a facility that contains nuts.

"B a r r y" wrote in message
...
On Mon, 12 Apr 2004 17:58:46 -0700, "RWM"
wrote:


As a follow up question, has any reputable research been done to analyze
the
effects of having a rider in your draft at different speeds.

There's been tons done on race cars. Of course, the speeds are a bit
different. G

FWIW, The common thinking in auto racing is that in a two car draft,
both cars are helped in a straight line. Cornering, there may or may
not be an advantage, due to changes in down force induced by the
draft. Usually, the more cars that join a single file draft, the
faster the pack goes.

Barry

I understand the effect in auto racing, but in addition to the speed the
front of the trailing car is much different than a bike.

Can anyone point me to research from bike racing?