Wheels and Tires for Velocity Squared

(Robert Milligan) wrote in message ...
I get the Velocity Thracian wheel set on my V2. Also put Cont
grand prix on front and rear. 20x1 1/8 26x1 . My pedals weigh
260g I am at less 2 mph faster with a top speed of 29 mph on the flats.
` Bob Milligan V2

On our Barcroft Columbia tandem we switched from the standard RANS
seat cushion to the thin seat cushion. To me the switch is not so
much about weight but freeing up the gluts from being immersed in foam
and thus neutralizing their use (Dave Balfour noticed this and after
the switch I tend to agree with him). What surprised me is the
comfort is still there (and less bouncing). As to the wheels etc. I
would suggest trying a different tire before forking out the big money
for wheels. The Schwalbe Marathon is a nice tough tire. I now ride
them on my Rocket. I switched from Comp Pools which had given me flat
problems. But the tradeoff is that they are noticeably slower than
the low rolling resistance tires. My solution, if you will consider a
narrower tire, is the Stelvio. I have them on my Barcroft Virginia.
Front tire is still original and no flats in 3200 miles. Back tire
was replaced at 1300 miles due to a sidewall cut and no flats on the
new one since then (1900 miles). And they have very low rolling
resistance An alternative is Continental Grand Prixs. They are
tough tires (I think a little tougher than Stelvios) and fast too, but
I found their ride to be a little harsher. If the change in tires
doesn't give you the increase you are looking for then look at new
wheels. Just a suggestion.

Mike S.
ST. Louis, MO.

Barcroft Virginia
Barcroft Columbia
RANS Rocket

mike s wrote:

... I switched from Comp Pools which had given me flat problems....
I have had only one flat on the Comp Pool on the back of my Sunset. The
tire was flat upon my return (by motor vehicle) from the invitational
ride in Havana, IL earlier this year. The tire was fine at the end of my
ride, but I let someone who shall remain nameless (but has an article
about the seat conversion on his Barcroft Virginia in the latest RCN)
ride my Sunset around the parking lot.

You may draw your own conclusions.

Tom Sherman – Close to 41½? N, 90½ W

mike s wrote:

... I switched from Comp Pools which had given me flat problems....
I have had only one flat on the Comp Pool on the back of my Sunset. The
tire was flat upon my return (by motor vehicle) from the invitational
ride in Havana, IL earlier this year. The tire was fine at the end of my
ride, but I let someone who shall remain nameless (but has an article
about the seat conversion on his Barcroft Virginia in the latest RCN)
ride my Sunset around the parking lot.

You may draw your own conclusions.

Tom Sherman – Close to 41½? N, 90½ W

Would it not depend on riding conditions ? If you are riding a flat
course and never accelerate or decelerate then a heavier "aero" rim would
be more efficient.

But if you were riding through town and stopping and starting many times
and dealing with cross winds then maybe the lighter less aero profile
would be more efficient.


On Sat, 27 Dec 2003 15:47:29 -0600, Tom Sherman wrote:


Mark Sperry wrote:

... Also saving weight on the wheels/tires results in a much greater energy
saving than on the seat....

Incorrect "conventional wisdom" dies hard.

Tom Sherman – Close to 41½? N, 90½ W

Would it not depend on riding conditions ? If you are riding a flat
course and never accelerate or decelerate then a heavier "aero" rim would
be more efficient.

But if you were riding through town and stopping and starting many times
and dealing with cross winds then maybe the lighter less aero profile
would be more efficient.


On Sat, 27 Dec 2003 15:47:29 -0600, Tom Sherman wrote:


Mark Sperry wrote:

... Also saving weight on the wheels/tires results in a much greater energy
saving than on the seat....

Incorrect "conventional wisdom" dies hard.

Tom Sherman – Close to 41½? N, 90½ W

swamprun wrote:

Would it not depend on riding conditions ? If you are riding a flat
course and never accelerate or decelerate then a heavier "aero" rim would
be more efficient.

But if you were riding through town and stopping and starting many times
and dealing with cross winds then maybe the lighter less aero profile
would be more efficient.

Note that the contention was that additional weight on the wheels is
much more of a detriment to performance than an identical weight
increase elsewhere on the bicycle. While it is true that it will take a
greater energy input to bring a bike with heavier wheels up to a given
speed than a bike of identical overall weight with lighter wheels, the
difference is too small to matter in most circumstances, and is
certainly much less than the old (incorrect) rule of thumb, "one pound
off the wheels is worth two pounds off the frame".

Tom Sherman – Close to 41.5 N, 90.5 W

swamprun wrote:

Would it not depend on riding conditions ? If you are riding a flat
course and never accelerate or decelerate then a heavier "aero" rim would
be more efficient.

But if you were riding through town and stopping and starting many times
and dealing with cross winds then maybe the lighter less aero profile
would be more efficient.

Note that the contention was that additional weight on the wheels is
much more of a detriment to performance than an identical weight
increase elsewhere on the bicycle. While it is true that it will take a
greater energy input to bring a bike with heavier wheels up to a given
speed than a bike of identical overall weight with lighter wheels, the
difference is too small to matter in most circumstances, and is
certainly much less than the old (incorrect) rule of thumb, "one pound
off the wheels is worth two pounds off the frame".

Tom Sherman – Close to 41.5 N, 90.5 W

On Sun, 28 Dec 2003 19:34:39 -0600, Tom Sherman wrote:
Note that the contention was that additional weight on the wheels is
much more of a detriment to performance than an identical weight
increase elsewhere on the bicycle. While it is true that it will take a
greater energy input to bring a bike with heavier wheels up to a given
speed than a bike of identical overall weight with lighter wheels, the
difference is too small to matter in most circumstances, and is
certainly much less than the old (incorrect) rule of thumb, "one pound
off the wheels is worth two pounds off the frame".

Tom Sherman – Close to 41.5 N, 90.5 W

So from a pure physics point of view the lighter wheel is in fact more
efficient, but the real world difference is trivial.

I suspect this and similar myths are important to the bicycle industry.

On Sun, 28 Dec 2003 19:34:39 -0600, Tom Sherman wrote:
Note that the contention was that additional weight on the wheels is
much more of a detriment to performance than an identical weight
increase elsewhere on the bicycle. While it is true that it will take a
greater energy input to bring a bike with heavier wheels up to a given
speed than a bike of identical overall weight with lighter wheels, the
difference is too small to matter in most circumstances, and is
certainly much less than the old (incorrect) rule of thumb, "one pound
off the wheels is worth two pounds off the frame".

Tom Sherman – Close to 41.5 N, 90.5 W

So from a pure physics point of view the lighter wheel is in fact more
efficient, but the real world difference is trivial.

I suspect this and similar myths are important to the bicycle industry.

What is the weight limit on Thacians?



--