What difference would a 115g saving in tyre weight make?

My bike presently has a set of Conti UltraSport 700cX25. If I change it
to a set of new Grand Prix 4000 with a saving of 115g/tyre, what
practical differences would I be able to feel during my rides? Is it a
weight saving that'll be obvious?

Thanks.
--

Artoi wrote:
My bike presently has a set of Conti UltraSport 700cX25. If I change it
to a set of new Grand Prix 4000 with a saving of 115g/tyre, what
practical differences would I be able to feel during my rides? Is it a
weight saving that'll be obvious?

2 x 115 = 230 grams which is about a half pound total. Strictly from a
weight standpoint, I don't think you'll notice a difference. But there
are other considerations such as casing thread count, tread pattern,
and traction.

The Ultra Sport 700x25 is 330g with a 3-ply casing and 84 tpi total.
That seems kind of heavy, and a low thread count that will increase
rolling resistance.

What kind of riding do you do?

Art Harris

Artoi wrote:
My bike presently has a set of Conti UltraSport 700cX25. If I change it
to a set of new Grand Prix 4000 with a saving of 115g/tyre, what
practical differences would I be able to feel during my rides? Is it a
weight saving that'll be obvious?

Thanks.
--

If somebody swapped the tires on your bike and didn't tell you, you
wouldn't notice any difference. However, if you pay $100 for new
tires, you'll immediately appreciate the faster, grippier, more
comfortable ride. (I'd wear the old ones out first.)

-Vee

In article . com,
"Art Harris" wrote:

Artoi wrote:
My bike presently has a set of Conti UltraSport 700cX25. If I change it
to a set of new Grand Prix 4000 with a saving of 115g/tyre, what
practical differences would I be able to feel during my rides? Is it a
weight saving that'll be obvious?

2 x 115 = 230 grams which is about a half pound total. Strictly from a
weight standpoint, I don't think you'll notice a difference. But there
are other considerations such as casing thread count, tread pattern,
and traction.

The Ultra Sport 700x25 is 330g with a 3-ply casing and 84 tpi total.
That seems kind of heavy, and a low thread count that will increase
rolling resistance.

What kind of riding do you do?

I was more interested in the dynamic effect of tyre weight. Just curious
what 115g/wheel difference would make to the ride.

As for the type of riding, well, definitely no races. Mostly exercises
around cycle paths as well as on roads. Weekly rides on the road with a
friend around 30km. But we do have a lot of hills here in Sydney and
figured the reduced dynamic weight may make climbing a bit easier. But
just can't quantify it as to by how much.
--

On Wed, 30 Aug 2006 11:43:17 GMT, Artoi wrote:

My bike presently has a set of Conti UltraSport 700cX25. If I change it
to a set of new Grand Prix 4000 with a saving of 115g/tyre, what
practical differences would I be able to feel during my rides?

Well, a bunch of guys in RBT will tell you that they think you're
foolish.

JT

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Artoi wrote:
My bike presently has a set of Conti UltraSport 700cX25. If I change it
to a set of new Grand Prix 4000 with a saving of 115g/tyre, what
practical differences would I be able to feel during my rides? Is it a
weight saving that'll be obvious?

Thanks.
--

Practical differences...less punctures with the Ultrasports...and less
expensive..seems like the choice is an easy one. Don't expect a lighter
tire to make a significant difference in your riding performance.

Artoi wrote:
My bike presently has a set of Conti UltraSport 700cX25. If I change it
to a set of new Grand Prix 4000 with a saving of 115g/tyre, what
practical differences would I be able to feel during my rides? Is it a
weight saving that'll be obvious?

Personally, I think you will notice the difference, probably as a
subtle new-found power in going up hills and accelerating (although it
is difficult to separate the rolling resistance from the weight
improvement), but unfortunately for you the gods of rbt will not allow
you to reduce your bike weight until you match LA's racing body fat %.

Artoi wrote:
I was more interested in the dynamic effect of tyre weight. Just curious
what 115g/wheel difference would make to the ride.

Ah, I think you mean "rotating weight" or rotational inertia. At a
steady speed, it will make no difference at all. When accelerating, it
theoretically makes a difference, but in cycling the effect is very,
very small (unless you are doing explosive accelerations).

Art Harris

Artoi wrote:
In article . com,
"Art Harris" wrote:

Artoi wrote:
My bike presently has a set of Conti UltraSport 700cX25. If I change it
to a set of new Grand Prix 4000 with a saving of 115g/tyre, what
practical differences would I be able to feel during my rides? Is it a
weight saving that'll be obvious?

2 x 115 = 230 grams which is about a half pound total. Strictly from a
weight standpoint, I don't think you'll notice a difference. But there
are other considerations such as casing thread count, tread pattern,
and traction.

The Ultra Sport 700x25 is 330g with a 3-ply casing and 84 tpi total.
That seems kind of heavy, and a low thread count that will increase
rolling resistance.

What kind of riding do you do?

I was more interested in the dynamic effect of tyre weight. Just curious
what 115g/wheel difference would make to the ride.

As for the type of riding, well, definitely no races. Mostly exercises
around cycle paths as well as on roads. Weekly rides on the road with a
friend around 30km. But we do have a lot of hills here in Sydney and
figured the reduced dynamic weight may make climbing a bit easier. But
just can't quantify it as to by how much.
--

Try zero, unless NASA is measuring your displacements with a laser
interferometer. However, both of these tires, like all Contis, are
relatively crappy as far as rolling resistance goes, but can be
durable. Look at the table below and realize that you are better off
with Michelin Carbon, or IRC Roadwinner or Triathlon, Avocet Road or
Duro (latter four not marked in these tables, but in other comparable
tables though). Michelin Dynamic is also probably better than
Ultrasport, for about the same price or cheaper.


Tire Crr Speed*
Delta

Deda Tre Giro d'Italia 0.0038 23.08
Vittoria Open Corsa Evo CX 0.0039 23.05
0.03
Michelin Pro 2 Race 0.0042 22.96
0.12
Vittoria Diamante Pro Rain 0.0044 22.90
0.18
Michelin Megamium 2 0.0047 22.81
0.27
Pariba Revolution 0.0048 22.78
0.30
Michelin Carbon 0.0050 22.72
0.36
Panaracer Stradius Pro 0.0051 22.69
0.39
Schwalbe Stelvio Plus 0.0052 22.66
0.42
Schwalbe Stelvio Evolution Front 0.0056 22.54
0.54
Continental GP Force (rear) 0.0057 22.51
0.57
Hutchinson Fusion 0.0057 22.51
0.57
Schwalbe Stelvio Evolution Rear 0.0057 22.51
0.57
Continental Ultra GatorSkin 0.0058 22.48
0.60
Ritchey Pro Race Slick WCS 0.0058 22.48
0.60
Schwalbe Stelvio 0.0059 22.45
0.63
Specialized S-Works Mondo 0.0061 22.39
0.69
Continental GP 3000 0.0067 22.21
0.87
*Hutchinson Top Speed 0.0069 22.15
0.93
Continental GP Attack (front) 0.0073 22.04
1.04

Vredestein Fortezza Piste 700 x 23c 145 0.0041
Michelin Axial Supercomp 700 x 20c 110 0.0045
Conti Grand Prix 3000 Silica 700 x 23c 120 0.0055
Conti Grand Prix 3000 Silica 700 x 28c 125 0.0060
Michelin Tracer 700 x 25c 90 0.0061
Michelin Tracer 700 x 25c 100 0.0062
Michelin Axial PRO 700 x 20c 110 0.0062
Michelin Axial PRO 700 x 23c 110 0.0063
Conti Supersport Ultra 700 x 18c 135 0.0065
Michelin World Tour 700 x 28c 100 0.0065
Hutchinson HP 25 700 x 25c 110 0.0067
Conti Grand Prix foldable 700 x 23c 120 0.0067
Michelin World Tour 700 x 28c 85 0.0071
Hutchinson HP 20 700 x 20c 110 0.0085
Conti Top Touring 700 x 32c 70 0.0087


Vittoria Open Corsa Evo CX 27.1 W
Michelin Pro 2 Race 29.2 W
Michelin Carbon 34.7 W
Panaracer Stradius Pro 35.4 W
Hutchinson Fusion 39.6 W
Continental Ultra GatorSkin 40.3 W
Continental Grand Prix 3000 46.6 W

*
in MPH
185lb rider + bike
250W rider output
CdA = .32m^2 (racing crouch, normal road bike)
Transmission efficiency = 96%
The test also included a calculation that on a flat 40 km time trial, a
rider with a 300 W power output would finish 2 minutes and 18 seconds
faster with the Deda Tre tyres than with Hutchinson Top Speed.
w

41 wrote:
Look at the table below and realize that you are better off
with Michelin Carbon, or IRC Roadwinner or Triathlon, Avocet Road or
Duro (latter four not marked in these tables, but in other comparable
tables though). Michelin Dynamic is also probably better than
Ultrasport, for about the same price or cheaper.

I tend to agree. I'm a big fan of the IRC Road Winner. Just curiuos
where you got the Crr values in your list.

Art Harris