wheel aerodynamics, was: mavic ksyrium elite vs velocity spartacus pro

[David]

In article <[email protected]>, Benjamin Lewis
<[email protected]> wrote:

> [email protected] wrote:
>
> > Make sure also that you are not getting a tailwind while you're testing the wheels. What you
> > thought might be the added boost riding with the peloton was probably the effect caused by some
> > external environmental help. Try to average your runs for the same route for at least a season
> > to see if the new wheels do help.
>
> Also, make sure your fitness level stays exactly the same.

Hmmm, I did say that I rode the wheels over and over and over again over the same flat course next
to an airport. Same fitness level, so are you telling me that with a 10km one way run and the back,
I will get a significant speed increase or decrease?

What I noticed is that, it's really your legs and your stamina that keeps the bike moving faster and
faster. Just these year, I went on a long 5 Western USA states tour and a tour up to the Queen
Charlottes for close to 6 months and climbed a lot of hills and passes and battled the brutal
headwind cycling North from Florence, Oregon. After ending the trip, I noticed I was much more fit.
Doing a day trip with my club riders, I suddenly was able to beat the guys on lighter bikes with
fancy wheels with just a bare touring bike with 700x32c and heavy T520 rims! That ought to tell you
why pros ride so strong. It's not the wheels they are riding that make them climb faster, it's
training and training day in and day out that makes them strong climbers and sprinters. I sold my
racing bike with the fancy wheels because I finally realized, I didn't need technological help after
all. I had the performance built inside me all along! Just keep training and riding and you'll see
that you don't need boutique wheels to ride strong!

 

[Benjamin Lewis]

[email protected] wrote:

> In article <[email protected]>, Benjamin Lewis <[email protected]> wrote:
>
>> [email protected] wrote:
>>
>>> Make sure also that you are not getting a tailwind while you're testing the wheels. What you
>>> thought might be the added boost riding with the peloton was probably the effect caused by some
>>> external environmental help. Try to average your runs for the same route for at least a season
>>> to see if the new wheels do help.
>>
>> Also, make sure your fitness level stays exactly the same.
>
> Hmmm, I did say that I rode the wheels over and over and over again over the same flat course next
> to an airport.

Ah, I didn't realize you were alternating your wheels when you were comparing them. Yes, this would
be a better comparison.

> Same fitness level, so are you telling me that with a 10km one way run and the back, I will get a
> significant speed increase or decrease?

Good lord, no -- I'm saying the opposite. I doubt that you'd see any speed change due to your wheels
at all, since the changes due to other factors such as wind, how tired you are that day, etc., will
be much, much larger than any theoretical difference the wheels may be making.

> What I noticed is that, it's really your legs and your stamina that keeps the bike moving faster
> and faster.

Yes, that was my point.

--
Benjamin Lewis

Clothes make the man. Naked people have little or no influence on society.
- Mark Twain

 

[Mike S.]

> No.. Don't need too. They ride Trek 5900s and Litespeeds with better wheels than I do as they came
> stock. I have no problems keeping up with them even with the stock 36 spoke wheels.

This begs the question: how fast are/were you riding these wheels?

I can vouch for the fact that at 56-60kph (35-37mph) they help! If you're wondering where I hit 35-
7mph, c'mon down to Thurs evening workouts at Fiesta Island.

Mike

 

[David]

In article <jt4Ob.32752$XD5.14241@fed1read06>, Mike S.
<mikeshaw2@coxDOTnet> wrote:

> > No.. Don't need too. They ride Trek 5900s and Litespeeds with better wheels than I do as they
> > came stock. I have no problems keeping up with them even with the stock 36 spoke wheels.
>
> This begs the question: how fast are/were you riding these wheels?

> I can vouch for the fact that at 56-60kph (35-37mph) they help! If you're wondering where I hit
> 35-7mph, c'mon down to Thurs evening workouts at Fiesta Island.
>

I'm sure they do if you want to believe them to be. But maybe, you already possess the power to go
that fast? At what speeds were you averaging at before you've got these fancy wheels?

 

[Mike S.]

> > > No.. Don't need too. They ride Trek 5900s and Litespeeds with better wheels than I do as they
> > > came stock. I have no problems keeping up with them even with the stock 36 spoke wheels.
> >
> > This begs the question: how fast are/were you riding these wheels?
>
> > I can vouch for the fact that at 56-60kph (35-37mph) they help! If
you're
> > wondering where I hit 35-7mph, c'mon down to Thurs evening workouts at Fiesta Island.
> >
>
> I'm sure they do if you want to believe them to be. But maybe, you already possess the power to go
> that fast? At what speeds were you averaging at before you've got these fancy wheels?

I CAN go that fast with normal wheels, but it is EASIER to go fast with the aero wheels.

Since I don't worry too much about average speed I can't begin to answer your question. AFAI am
concerned average speed is worthless for what I do. Who gives a rat's ass what your average speed is
if you can't win the field sprint?

Mike Mike

 

[Carl Fogel]

"Mike S." <mikeshaw2@coxDOTnet> wrote in message news:<jt4Ob.32752$XD5.14241@fed1read06>...
> > No.. Don't need too. They ride Trek 5900s and Litespeeds with better wheels than I do as they
> > came stock. I have no problems keeping up with them even with the stock 36 spoke wheels.
>
> This begs the question: how fast are/were you riding these wheels?
>
> I can vouch for the fact that at 56-60kph (35-37mph) they help! If you're wondering where I hit
> 35-7mph, c'mon down to Thurs evening workouts at Fiesta Island.
>
> Mike

Dear Mike,

Assuming that you're hitting 35-37 mph on a flat section, I'm impressed. But a 2 mph speed variation
is less than expected on a day-to-day basis from ordinary light winds.

My daily downhill run here in Colorado, for example, is a bit over two and a half miles (from 8.65
miles to 11.24 miles) from the road stake at the top of the ridge west of town down to the blue
manhole cover half a mile out on the river bottom and 400 feet lower.

In sixteen rides since the beginning of the year, my average speed for this section has varied
day-to-day from 25.5 to 32 mph, or over 6 mph. Some days, I roll hundreds of yards further than
usual before my speed drops to 24 mph and I start pedalling again. Other days, I have to pedal a
lot earlier.

At higher speeds, even greater variation due to normal wind conditions would be expected because
wind resistance is non-linear. A 5 mph wind, which is scarcely noticeable when we're walking, has
little effect on a bicycle at 10 mph, some at 15 mph, more at 20 mph, and quite a bit at 30 mph.

Have a look at your speedometer for a dozen rides on the same route and record the maximum speed.
The variation may surprise you. It's usually far more than any claimed improvement from equipment.
This doesn't mean that the equipment offers no advantage, just that any small advantage is often
masked by other factors.

Carl Fogel

 

[David]

In article <%jkOb.34220$XD5.21583@fed1read06>, Mike S.
<mikeshaw2@coxDOTnet> wrote:

> > > > No.. Don't need too. They ride Trek 5900s and Litespeeds with better wheels than I do as
> > > > they came stock. I have no problems keeping up with them even with the stock 36 spoke
> > > > wheels.
> > >
> > > This begs the question: how fast are/were you riding these wheels?
> >
> > > I can vouch for the fact that at 56-60kph (35-37mph) they help! If
> you're
> > > wondering where I hit 35-7mph, c'mon down to Thurs evening workouts at Fiesta Island.
> > >
> >
> > I'm sure they do if you want to believe them to be. But maybe, you already possess the power to
> > go that fast? At what speeds were you averaging at before you've got these fancy wheels?
>
> I CAN go that fast with normal wheels, but it is EASIER to go fast with the aero wheels.

But how fast with normal wheels (numbers please)?? I mean, what you are saying is a subjective
thing. With aero wheels, it's easier to go fast but with normal wheels I can go that fast. I mean,
it really does not make any sense you are the engine and your body cross section is much much wider
than any skinny tires or aero wheels you have on.

> Since I don't worry too much about average speed I can't begin to answer your question. AFAI am
> concerned average speed is worthless for what I do. Who gives a rat's ass what your average speed
> is if you can't win the field sprint?
>

But isn't that what people looked at when buying these wheels?? I mean, most of the reason why
boutique wheels still attract the new cycling crowd is because, they are all looking for a quick
fix. Just like the diet industry with the Atkins diet. A quick fix without the need to train and
more training. More than often, people are not looking for a field sprinting finish. They are
looking at keeping up with the fast group in sagged tours. I had been in many sagged tours and I
keep seeing newbies with these wheels, believing that that's what needed to go fast. Then, I meet
40-50 year old athletic fit men and ladies with well used and well cared for bikes and standard but
proven equipment and wheels climb mountain passes and sprint just as fast as the young guns and
their fancy carbon and paired spoke wheels.

The reason I wanted to know your average speed is because, wind resistance is variable in different
riding conditions. It's especially bad when it's raining hard. That's why, I tested my wheels in all
different climates, terrain and riding fitness to gauge the effectiveness of these wheels.. My
average speed on any given time can be in between 25mph to 33mph. In a peloton, 40mph is possible if
I have a couple of strong riders breaking wind at the front. Breaking wind is a tough thing to do
and many smart professional cyclists like Lance Armstrong isn't stupid enough to be out in front all
the time. If these aerowheels somehow can magically break wind so effectively without the need of a
peloton, then you would see Lance Armstrong riding solo rather than be surrounded by his own pack on
the flats??

Aero drag is much noticeable when riding above 20mph, but if you're just standing still, a slight
headwind isn't that noticeable. Also make note that you are working against the wind and hence, you
are putting more power than you are used to. Assuming you can do 35-37mph, but for how long? I try
to ride a solo century (100 miles) if I can every week to keep fit and I tell you, my best average
is about 25mph along 1 mountain pass (well a 10% hill) and a flat section next to an airport where
I'm going to get major headwind and a couple of steep downhills afterwards. So, I really cheer for
you that you can do 35-37mph with these fancy wheels.

 

[Dmitri Colebatc]

"Mike S." <mikeshaw2@coxDOTnet> wrote in message
news:NTJNb.25280$XD5.20468@fed1read06...

[snip]

>
> To the OP: you tried any of your friend's wheels yet? What did you feel?
>

Been away a few days, sorry. No - he's away, and has his bike with him.... he'll be back next sunday
(25th) so wont be till then... will report back at that stage though.

cheers dim