Bontrager Race X-lite versus Continental GP3000 tires
Bob Palermo
The original tires on my road bike were Bontrager Race X-lites 23mm. After
2500 miles, some of which was on the trainer, my rear tire was worn out. I
only had one flat on it and that was right at the very end of life. My LBS
recommended the Conti GP3000 as a replacement, so I got it. After a couple
of hundred miles, my impression is that it's a slower tire than the X-lite.
My ride average speeds seem to be about .5 mph slower. Has anyone else used
both these tires? If so, what are your observations?
After I bought the tire, I found out that the GP3000 has been replaced by
the GP4000. In fact my LBS had both, with the GP4000 about $5 more
expensive. They didn't even mention the GP4000 when we were looking at the
choices. I probably would have spent the extra $5 since the 4000 is supposed
to be faster and more durable.
Thanks,
Bob P.
Barnard Frederick
It's not the tire, it's the engine that is slower. You could put a
cheap $10 wire bead tire on your bike and it wouldn't affect your
average speed by anywhere near that much. The GP3000 was/is a high end
racing tire used and respected by thousands of riders the world over.
I'd be amazed if anyone could prove it was somehow slower than any other
tire.
Qui si parla Campagnolo
Doubt one is ''slower' than another. Differences in rolling resistence
is mostly teeny, lost in the noise. Remember that GP series of tires,
like lots of others at this high price point, are racing tires with the
associated sticky-ness, light weight and less durability. Perhaps a
more appropriate tire, that costs $15-$25 less would be a better idea.
>
> Bob P.
Bob Palermo
of an average speed difference that it couldn't be due to the tire. Also,
it's the same engine (me), with just a different tire. My times for various
courses have been quite consistent, actually improving, for quite some time.
After switching tires and doing the same courses, with the same percieved
effort levels, I noticed roughly the 0.5 mph slip.
But you might be right. Perhaps my skepticism about the tire is showing in
my performance.
Bob P
"Barnard Frederick" <loco...@spamcast.net> wrote in message
news:MPG.1f520fcba...@newsgroups.comcast.net...
Bob Palermo
I'm not too concerned about additional durability. If I can get 2500 miles
on a rear tire, I'm pretty happy. That's what I got on my X-lite. Won't a
cheaper tire be heavier and thus slower. The average speed for my rides is
in the 19-20 mph range, and I'm not out killing myself to do it. To me, it
wouldn't be worth the $30 or $40 a year savings (the difference in cost of 2
tires) ir it meant that I'd lose some performance.
Bob P.
"Qui si parla Campagnolo" <pe...@vecchios.com> wrote in message
news:1156079455.2...@74g2000cwt.googlegroups.com...
Barnard Frederick
> Really. 0.5 mph (half a mile per hour per hour) doesn't seem like that much
> of an average speed difference that it couldn't be due to the tire. Also,
> it's the same engine (me), with just a different tire. My times for various
> courses have been quite consistent, actually improving, for quite some time.
> After switching tires and doing the same courses, with the same percieved
> effort levels, I noticed roughly the 0.5 mph slip.
>
> But you might be right. Perhaps my skepticism about the tire is showing in
> my performance.
>
> Bob P
A 0.5 difference is very significant for me. That's about the
difference I saw going from my hot rod hybrid (mixture of mountain and
road racing components) which was recently stolen, and a high end road
bike (Giant OCR Comp 1). The new bike is 4 lbs. lighter and has a much
more aero position.
Really, the GP3000 is about as good as it gets for a high performance
tire. And there are many variables when you look at average speed, like
wind speed and direction, how often you are forced to stop, your own
motivation and energy level, etc. You use a computer, so are you sure
the tire diameter is the same? I wouldn't think that would make much
difference, but actual tire width varies even though they may have the
same nominal size. That's one reason computers allow you to put in a
custom size.
Marko
carl...@comcast.net
>GP3000 is very slow
>http://www.rouesartisanales.com/article-1503651.html
Dear Marko,
Here's the table for clinchers, including the gp3000, from that link:
http://ddata.over-blog.com/xxxyyy/0/02/72/10/clincher-specs.html
The easiest-rolling tires are listed first. The GP3000 appears near
the bottom with a rolling resistance of 0.0067.
Bontrager X-Lites weren't tested, but they'd be about 0.0050 if they
were in the middle of the pack.
Here's a calculator that allows changing the rr value:
http://w3.iac.net/~curta/bp/velocityN/velocity.html
For 200 watts and the default 0.0050 rr, it predicts 31.88 kmh.
Raising the rr to the gp3000's 0.0067 rr produces 31.02 kmh, a drop of
0.86 kmh or 0.534 mph.
While a half-mph speed drop change isn't likely to be obvious while
riding alone, it will certainly show up on timed runs over the same
daily course.
Cheers,
Carl Fogel
Barnard Frederick
> GP3000 is very slow
> http://www.rouesartisanales.com/article-1503651.html
I find this hard to believe, but maybe I'm wrong on this one. Looks
like the OP should get my favorite tire--the Michelin Pro Race.
Lou Holtman
> Marko says...
>
>
>>GP3000 is very slow
>>http://www.rouesartisanales.com/article-1503651.html
>
>
> I find this hard to believe, but maybe I'm wrong on this one.
No it was measured in various tests.
> Looks
> like the OP should get my favorite tire--the Michelin Pro Race.
Yep, it's a better tire IMO.
Lou
--
Posted by news://news.nb.nu
C Wright
MPG.1f5260bef...@newsgroups.comcast.net, "Barnard Frederick"
<loco...@spamcast.net> wrote:
These stats are very interesting, but I also view them with a little bit of
skepticism. The GP 3000 has more rolling resistance than the Ultra Gator
Skin? Is anyone aware of a similar test on the newer GP 4000? Also the
Bontrager Race X Lite was not tested so one can only speculate.
For the record, I have also ridden the Race X Lites and both the GP3000 and
the GP4000. My impression also was that the the GP3000 was slightly slower
than the Bontrager. I tended to chalk that up to differences in riding
conditions - but maybe the GP3000's are slightly slower! I also felt that
the GP3000's (and the 4000's) got a little faster after getting worn down a
bit.
Chuck
Bob Palermo
It's only the rear tire that has been replaced. My computer uses the front
tire. So, it's not an issue of the tire diameter. It's probably just my
skepticism about the change.
Slightly off topic : A while back, I calibrated my computer based on a fixed
course with mile markers. The calibration resulted in a value almost exactly
as that from the tire size table for my cateye.
"Barnard Frederick" <loco...@spamcast.net> wrote in message
news:MPG.1f524f66d...@newsgroups.comcast.net...
Qui si parla Campagnolo
Bob Palermo wrote:
> Hi. Why do you suggest a cheaper tire?
>
> I'm not too concerned about additional durability. If I can get 2500 miles
> on a rear tire, I'm pretty happy. That's what I got on my X-lite. Won't a
> cheaper tire be heavier and thus slower. The average speed for my rides is
> in the 19-20 mph range, and I'm not out killing myself to do it. To me, it
> wouldn't be worth the $30 or $40 a year savings (the difference in cost of 2
> tires) ir it meant that I'd lose some performance.
>
> Bob P.
Chepaer tires are a harder rubber and 'may' offer less rolling
resistence and less traction as well. Lighter isn't faster,
necessarily. I think i would look elsewhere as to why these tires
'feel' slower to the tune of .5mph...tires don't make that much
difference IMo-check the differences in rolling resistence, the number
differences are teeny/tiny.
carl...@comcast.net
Dear Chuck,
Why be skeptical? The test showing poor Conti performance was
conducted at the Contintental facilty:
"Testing was conducted at the Continental fascilities in Korbach -
Germany."
"The Coefficient of Rolling Resistance (Crr), was aquired by testing
all tires on a 120 cm (47.244") drum at 30 km/h (18.64 mph). Loading
was similated with a 44/56% balance of front and rear tire. Total bike
including rider weight was 85 kg (187.39 lbs)."
http://www.rouesartisanales.com/article-1503651.html
Note the picture of the equipment.
The rolling resistance tests tend to agree with each other:
This one from 2001 shows the GP3000 silca 700 x 25 120 psi at rr
0.0055, the GP3000 700 x 28 125 psi at rr 0.0060, and the GP folding
700 x 23 120psi at rr .0067:
http://www.airfreetires.com/TireData/
This one from 1998-2002 shows Grand Prix 25-559 (700x25) testing at
0.0063 to 0.0069 at 120 psi:
http://www.legslarry.beerdrinkers.co.uk/tech/JL.htm
Cheers,
Carl Fogel
carl...@comcast.net
<pe...@vecchios.com> wrote:
Dear Peter,
The speed calculators suggest that a "teeny" difference in rr produces
exactly the kind of 0.5 mph difference that Bob mentions:
http://groups.google.com/group/rec.bicycles.tech/msg/ef101cca2498cdc6
Cheers,
Carl Fogel
Qui si parla Campagnolo
Bob Palermo wrote:
> Hi. Why do you suggest a cheaper tire?
>
> I'm not too concerned about additional durability. If I can get 2500 miles
> on a rear tire, I'm pretty happy. That's what I got on my X-lite. Won't a
> cheaper tire be heavier and thus slower. The average speed for my rides is
> in the 19-20 mph range, and I'm not out killing myself to do it. To me, it
> wouldn't be worth the $30 or $40 a year savings (the difference in cost of 2
> tires) ir it meant that I'd lose some performance.
>
> Bob P.
I have a suggestion...trundle on down to your local Trek dealer and get
a pair of X-lites...
Antti Salonen
> It's not the tire, it's the engine that is slower. You could put a
> cheap $10 wire bead tire on your bike and it wouldn't affect your
> average speed by anywhere near that much. The GP3000 was/is a high end
> racing tire used and respected by thousands of riders the world over.
> I'd be amazed if anyone could prove it was somehow slower than any other
> tire.
There's no need for guesswork, as rolling resistance of different racing
tyres has been measured, for example last October by the German magazine
Tour. The differences between 23 mm racing tyres of similar weight were
bigger than many people would expect. Continentals tended to be close to
the bottom. The slowest tyre (Continental GP Attack) had almost twice
the rolling resistance of the fastest ones.
Actual speed difference depends on tyre pressure, load and wattage, but
with same parameters the difference between for example GP3000 and
Michelin Pro Race really can be 0.5 mph or even more. That's still close
to impossible to notice by the rider, because there are many other
variables and it is easily lost in the noise.
The numbers should be available at this URL, but right now it doesn't
seem to load for me:
http://www.rouesartisanales.com/article-1503651.html
-as
Bob Palermo
X-lites there but they recommended the GP3000 over the X-lites.
Bob P.
"Qui si parla Campagnolo" <pe...@vecchios.com> wrote in message
news:1156099328.3...@i3g2000cwc.googlegroups.com...
Bob Palermo
Thanks for the table and the calculations. Given that the average speed for
my rides are usually in the 19.x to 20.x mph range, the calculations are in
the ballpark. Of coures, they assume a lower rolling resistance for the
x-lites, which we don't really know right now.
The table makes me want to get the Michelin Pro2 Race.
<carl...@comcast.net> wrote in message
news:nj3he2hoj6rn5n693...@4ax.com...
carl...@comcast.net
<antti....@helsinki.if.invalid> wrote:
Dear Anti,
That's the one that other posts have mentioned:
http://www.rouesartisanales.com/article-1503651.html
It seems to be working now.
This is the link to the clincher results:
http://ddata.over-blog.com/xxxyyy/0/02/72/10/clincher-specs.html
Cheers,
Carl Fogel
Barnard Frederick
> There's no need for guesswork, as rolling resistance of different racing
> tyres has been measured, for example last October by the German magazine
> Tour. The differences between 23 mm racing tyres of similar weight were
> bigger than many people would expect. Continentals tended to be close to
> the bottom. The slowest tyre (Continental GP Attack) had almost twice
> the rolling resistance of the fastest ones.
>
> Actual speed difference depends on tyre pressure, load and wattage, but
> with same parameters the difference between for example GP3000 and
> Michelin Pro Race really can be 0.5 mph or even more. That's still close
> to impossible to notice by the rider, because there are many other
> variables and it is easily lost in the noise.
>
> The numbers should be available at this URL, but right now it doesn't
> seem to load for me:
>
> http://www.rouesartisanales.com/article-1503651.html
>
> -as
See another part of this thread. Another interesting fact is that
tubulars faired worse on average than clinchers. If the calculator Carl
linked to was correct, I have to wonder why so many pros still use
tubulars. The weight savings if we assume a latex tube in the clincher
is pretty much nil.
carl...@comcast.net
Dear Barnard,
The pros still use tublars for a number of reasons.
For one thing, the tubular rim has no real flanges, so it's lighter
than the clincher rim. The overall weight savings may be bigger than
you'd think at first.
The pro can keep riding a flat tubular while waiting for his support
car to arrive, since the tubular is glued to the rim. A flat clincher
is much harder, if not impossible, to keep going.
(The pro has that support car and a mechanic to take care of the
drudgery of gluing all those tubulars. Ordinary riders carry spare a
whole spare tubular, killing any weight savings, and either plan on no
more than one flat or else borrowing a second spare tubular from their
riding companions.)
The much shallower rim profile of a tubular wheel reduces pinch flats,
so the pro can run lower tire pressures with less fear of flats.
The lower pressures (and the tubular squirming on soft glue as opposed
to track shellac) may increase rolling resistance, but the lower
pressure gives a more comfortable ride, which is prized in day and
week long races.
There are also claims that tubulars corner and "feel" better. The
lower pressures might well improve cornering traction a little.
Then there's tradition. Pros race on tubulars because tubulars really
were better for many years than the clunky clinchers that were
available. Clinchers improved, but it's hard to change.
So pros still tend to train on cheaper clinchers and save their
expensive tubulars for races. The comfort, cornering, and
flat-resistant advantages of tubulars may still outweigh the slight
speed advantages of clinchers.
Cheers,
Carl Fogel
Ron Ruff
Bob Palermo wrote:
> The table makes me want to get the Michelin Pro2 Race.
Or maybe the Michelin Carbon or Megamium (more durable tires) for the
rear...? Here is another table from last fall when this first came up.
The difference between tires is much greater than I would have
expected.
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
*
in MPH
185lb rider + bike
250W rider output
CdA = .32m^2 (racing crouch, normal road bike)
Transmission efficiency = 96%
Qui si parla Campagnolo
Bob Palermo wrote:
> My LBS is a Trek dealer. It's where I got my bike, a Trek 2300. They have
> X-lites there but they recommended the GP3000 over the X-lites.
>
> Bob P.
Why? better margin(hard to believe with any Bontrager/Trek product)? No
size in stock? Beef with Mr Burke and Bontrager?
Steve knight
I test tire speed by coasting down this hill that's right in front of
my house. every day check and average the speed. it works pretty well
if you start at the same speed and keep track of the wind and tire
pressure.
Bill Wright
rj_pa...@comcast.net says...
> Marko, Carl,
>
I have Continental GP4000's
Does anyone know how these rate for rolling resistence?
I'm pleased with them, have riden 2000 miles with them.
Bill Sornson
> I have Continental GP4000's
> Does anyone know how these rate for rolling resistence?
> I'm pleased with them, have riden 2000 miles with them.
If you're pleased with them, then what does it matter?
Perception trumps reality... BS
carl...@comcast.net
Dear Bill,
Here's a claim that the GP 4000 has 20% less rolling resistance than
the unimpressive GP 3000:
The claim probably comes from Continental and is just repeated by the
seller. Reducing the GP 3000's rr of 0.0067 would put the GP 4000
around 0.0054, which is much better.
One possible reason for the improvement is the use of a different
material:
http://www.roadcycling.com/news/article1395.shtml
Note, however, that the writer is using the seat of his pants to
produce an article best characterized by these phrases:
silky, very easy, solid, more than capable, great success, did not
even flinch (who ever saw a tire flinch?), smooth as glass, precise
and stable, great, confidently, very happy, smooth, very responsive,
ecstatic, definitely, perfectly, etc.
Cheers,
Carl Fogel
41
Barnard Frederick wrote:
> Marko says...
>
> > GP3000 is very slow
> > http://www.rouesartisanales.com/article-1503651.html
>
> I find this hard to believe
Why would you find it hard to believe? If you look at the construction,
the GP3000 has many energy-wasting features:
-relatively coarse casing material: 86 TPI instead of 127tpi as used in
fine tires
-two extra belts of this relatively coarse material
-relatively thick tread rubber (otherwise a good feature, for
durability).
Note that Conti says 430tpi or some such, but they are counting all
five layers: divide by 5 to get the figure everyone else uses.
No surprise it's slow.
The fastest tires are the least durable, no doubt about that. But there
are much better and more intelligent compromises. Some of the best seem
to be the Michelin Carbon/Krylium and the Avocet Carbon 12 series; as
well as the corresponding IRC tires, like the IRC Triathlon. These are
way less expensive. Note that these all have carbon tread rubber, for
best durability and traction, unlike silica tread rubber which can give
unfortunate results in the wet and is not as durable anyway.
As you can see, the differences between fine tires are relatively small
and hard to notice. That's why pros are still majority (not all, by any
means) still using tubulars. They won't be proven wrong just by feel.
Why are any pros still using Conti tires? If you can fool them with
those, you can fool them with tubulars too, the fine ones of which are
considerably better than the Conti clinchers, which some racers do use.
41
Bob Palermo wrote:
> Hi,
>
> The original tires on my road bike were Bontrager Race X-lites 23mm. After
> 2500 miles, some of which was on the trainer, my rear tire was worn out. I
> only had one flat on it and that was right at the very end of life. My LBS
> recommended the Conti GP3000 as a replacement, so I got it. After a couple
> of hundred miles, my impression is that it's a slower tire than the X-lite.
> My ride average speeds seem to be about .5 mph slower. Has anyone else used
>
> After I bought the tire, I found out that the GP3000 has been replaced by
> the GP4000. In fact my LBS had both, with the GP4000 about $5 more
> expensive. They didn't even mention the GP4000 when we were looking at the
> choices. I probably would have spent the extra $5 since the 4000 is supposed
> to be faster and more durable.
Try Avocet Road (25mm) or Criterium (23mm). These have 127tpi casings
unlike the Conti at 86tpi, and don't have the energy wasting extra two
belts. Tread thickness on the Road is 1.5mm of carbon rubber, Criterium
1.25mm. IRC Triathlon is similar to one or both of these, but nowadays
only available with kevlar puncture belt, which must suck some energy.
These tires are all better designed and way cheaper than the Contis.
For most purposes and people, 25mm is a better bet for a fast tire than
23. More durable, more comfortable ride.
{
Antti Salonen
> These stats are very interesting, but I also view them with a little bit of
> skepticism. The GP 3000 has more rolling resistance than the Ultra Gator
> Skin?
I don't see any reason why the GP 3000 should be any faster than the
Ultra GatorSkin. They are both of similar weight and construction. The
GP 3000 was never a top-class racing tyre, having a relatively stiff and
thick canvas.
> Is anyone aware of a similar test on the newer GP 4000?
There's a comparison between GP 3000 and GP 4000 on the Continantal web
page:
http://www.conti-tyres.co.uk/conticycle/ti%20grand%20prix%204000.shtml
The rolling resistance numbers would indicate that the GP 4000 would be
somewhere in the midpack in test results already mentioned in this
thread. The tyre pressure in the tests was different, but the test
setup probably comparable because the mentioned tests were performed at
Continental.
Like the GP 3000, GP 4000 seems to be a very puncture resistant,
long-lasting and reliable tyre. It's probably somewhat faster but still
not top-class. I'm convinced that it is a great choice for training,
but I'd definitely use something else for racing.
-as
Antti Salonen
> Try Avocet Road (25mm) or Criterium (23mm). These have 127tpi casings
> unlike the Conti at 86tpi, and don't have the energy wasting extra two
> belts. Tread thickness on the Road is 1.5mm of carbon rubber, Criterium
> 1.25mm. IRC Triathlon is similar to one or both of these, but nowadays
> only available with kevlar puncture belt, which must suck some energy.
> These tires are all better designed and way cheaper than the Contis.
I guess it must depend on where you live, because I've bought my
GP4000's for 23 euros a piece from mail order. I've also tried Avocets,
but because they are almost impossible to find in Europe they end up
being much more expensive. They are definitely nice tyres, but I also
experienced more than their share of punctures with them, especially
compared to Continentals.
-as
41
Antti Salonen wrote:
> 41 <KingGe...@yahoo.fr> wrote:
>
> > Try Avocet Road (25mm) or Criterium (23mm). These have 127tpi casings
> > unlike the Conti at 86tpi, and don't have the energy wasting extra two
> > belts. Tread thickness on the Road is 1.5mm of carbon rubber, Criterium
> > 1.25mm. IRC Triathlon is similar to one or both of these, but nowadays
> > only available with kevlar puncture belt, which must suck some energy.
> > These tires are all better designed and way cheaper than the Contis.
>
> I guess it must depend on where you live, because I've bought my
> GP4000's for 23 euros a piece from mail order. I've also tried Avocets,
> but because they are almost impossible to find in Europe they end up
> experienced more than their share of punctures with them, especially
> compared to Continentals.
Yes, as you can see from <http://tinyurl.com/jcbjm> or
<http://tinyurl.com/zy47l> (Nashbar and Sheldon respectively), high-end
Continental tires tend to be extremely expensive in North America, i.e.
about twice the price of the Avocets. In turn, you can get the IRC
version of the Avocets for about half that price. As far as I can tell
the IRC are close but not quite exactly the same, with some confusion
over the sizing. The rubber on the Avocets may also be a little harder.
Unfortunately, the IRC versions are now all only available with energy
sucking, money-wasting, kevlar belt.
Conti tires have that five-layer carcass, relatively thick nylon (86tpi
vs 127tpi), plus relatively thick tread rubber, so they should be
relatively puncture resistant (and relatively slower). I have a folding
Ultra 2000 to use as a spare, and it seems a reasonable tire: the 57tpi
casing is not so much worse than the 66tpi of my Avocet Duro Plus,
while the tread rubber of the Conti is thicker at the middle, but does
not wrap nearly as far up the sidewalls. Also, unlike most other
brands, Avocet rubber gets thicker as the tire size goes up. I imagine
those using the Criterium or Time Trial (1.25mm and 1.0mm thick
respectively) would find them a little thin compared to Conti rubber,
and this is why they are faster. But the rubber is harder and so wears
better. The thickness of the Road model is 1.5 mm, and I expect
therefore the Duro to be 1.75mm and the Duro Plus to be 2.0mm. These
latter three are definitely very durable tires. The Michelin Carbon,
with 127tpi casing but strangely an extra fourth bead to bead layer,
and very thick (comparable to Conti), hard, carbon tread rubber, was
found in all these tests to have low rolling resistance, excellent
wear, and very good puncture resistance. The tread rubber does not wrap
up as far up the sidewalls as the Avocets, and they too are about twice
the price, and the size only goes up to 25mm. But I really like those
brown Conti sidewalls, to the extent they are still available.
I imagine almost everyone on this newsgroup would be perfectly well
served by cheap Michelin Dynamics in whatever size.
a
Antti Salonen
> I imagine
> those using the Criterium or Time Trial (1.25mm and 1.0mm thick
> respectively) would find them a little thin compared to Conti rubber,
> and this is why they are faster. But the rubber is harder and so wears
> better.
For what it's worth, I wore two new Avocet Criteriums down to the canvas
in about 3000 km as a rear tyre. I'm barely 70 kg WITH the bike and all
equipment so that's kind of dissappointing. As a comparison a
Continental Grand Prix 4-Season lasted 7000 km. Both tyres are 23 mm
wide and about 220 grams.
What comes to puncture resistance I had several flats with Avocets
especially in wet conditions and when the rubber was already thin. I've
had a flat or two with Continentals over about 20 thousand km, but the
incidence rate is about five times less than with Avocets. It could be
just terrible luck, but it really smells like something statistically
significant.
I guess this is when somebody will jump up yelling that flats are all
about rider skill.
-as
41
Antti Salonen wrote:
> 41 <KingGe...@yahoo.fr> wrote:
>
> > I imagine
> > those using the Criterium or Time Trial (1.25mm and 1.0mm thick
> > respectively) would find them a little thin compared to Conti rubber,
> > and this is why they are faster. But the rubber is harder and so wears
> > better.
>
> For what it's worth, I wore two new Avocet Criteriums down to the canvas
> in about 3000 km as a rear tyre. I'm barely 70 kg WITH the bike and all
> equipment so that's kind of dissappointing. As a comparison a
> Continental Grand Prix 4-Season lasted 7000 km. Both tyres are 23 mm
> wide and about 220 grams.
According to Conti and Avocet spec, in Kevlar bead for both, the
GP4-season in 23 is 220g, the Avocet Criterium is 200g. The Criterium
with wire bead is 235g.
Were these the blackwall made in Korea Criteriums, or the tanwall made
in Japan ones? And what year of production? According to Jobst, at
least for some production runs of the made in Korea ones, they reversed
the thicknesses of the two tread layers, i.e. making the hard durable
rubber outer layer thin, and the soft sticky non-durable inner layer
thick. I don't know if current production still has the same defect,
and I presume he doesn't either, since he bought what he has in a big
batch, as I understand it. At your wear rate, the road model at 1.5mm
would give roughly 3600km of wear, while I believe Jobst reports
something like 4-6000km as typical (for the original Japanese
production).
> What comes to puncture resistance I had several flats with Avocets
> especially in wet conditions and when the rubber was already thin.
Of course, these are the worst conditions for any tire. Would you say
the objects that penetrated were at least about 3-4mm thick? If so, I
believe they would have penetrated the Contis as well. I don't know
their thickness, but I imagine the total carcass+tread at the thickest
point, the very centre, to be no greater than 3-4mm. For the
Criteriums, say .6mm+1.25MM = 1.85mm? For the Contis, it should be
about 1.5mm+ I don't know, 2.5mm, to account for the fact that you got
about twice the mileage from them. As you can see, this explains why
the Contis are so relatively slow. But note that the thickness of Conti
tread rubber drops off very fast as you go away from the centre, unlike
Avocets. Is most of your riding in a straight line?
>I've
> had a flat or two with Continentals over about 20 thousand km, but the
> incidence rate is about five times less than with Avocets. It could be
> just terrible luck, but it really smells like something statistically
> significant.
>
> I guess this is when somebody will jump up yelling that flats are all
> about rider skill.
Well, at the centre, by my guesstimate they are about twice as thick as
the Avocet Criteriums. However, the sidewalls are much more exposed. If
you rode gravelly trails and dirt roads with the Contis, you might not
have quite the same luck. The Avocets seem to be designed to mimic the
old Clement tubulars, the ones designed for the old unpaved, twisty
roads of the Giro and the Tour and the Vuelta.
The Criterium is not the ideal Avocet tire. I think the Road, the Duro,
and the Duro Plus are where the series really shines.
±
Antti Salonen
> According to Conti and Avocet spec, in Kevlar bead for both, the
> GP4-season in 23 is 220g, the Avocet Criterium is 200g. The Criterium
> with wire bead is 235g.
>
> Were these the blackwall made in Korea Criteriums, or the tanwall made
> in Japan ones? And what year of production?
They were actually both about 220 g - I'm actually one of those sad
types who weigh bike parts. The Avocet model was Criterium SL (kevlar
bead), black side wall, bought last year from Harris Cyclery.
> But note that the thickness of Conti
> tread rubber drops off very fast as you go away from the centre, unlike
> Avocets. Is most of your riding in a straight line?
I guess it is, but whose really isn't? I've done my riding in the Alpine
passes, and even there you're within a few degrees from vertical 99 % of
the time.
> Well, at the centre, by my guesstimate they are about twice as thick as
> the Avocet Criteriums. However, the sidewalls are much more exposed. If
> you rode gravelly trails and dirt roads with the Contis, you might not
> have quite the same luck. The Avocets seem to be designed to mimic the
> old Clement tubulars, the ones designed for the old unpaved, twisty
> roads of the Giro and the Tour and the Vuelta.
That is why I think the GP 4-Season and also the Ultra GatorSkin are
both very good tyres for dirt roads or otherwise adverse conditions.
They have what Continental calls "Duraskin" sidewalls, and I haven't
heard of anybody having problems with them. If you look at the
lightweight 23 mm tyres on the market, I think they are definitely
among the most dependable.
> The Criterium is not the ideal Avocet tire. I think the Road, the Duro,
> and the Duro Plus are where the series really shines.
Could be. I put a pair of Duro K's on my girlfriend's bike, and
they've been fine and reliable. Avocets are nice tyres, if they're
available to you at a reasonable price.
In Europe, if you want a nice smooth tyre with carbon black rubber, for
example Michelin Krylion (previously called Carbon) is a great deal.
According to the rolling resistance tests it's pretty fast, and it has
a reputation of great mileage and reliability. Besides, being less than
25 euros a piece in mail order, what's not to like?
-as
41
Antti Salonen wrote:
> 41 <KingGe...@yahoo.fr> wrote:
>
> > According to Conti and Avocet spec, in Kevlar bead for both, the
> > GP4-season in 23 is 220g, the Avocet Criterium is 200g. The Criterium
> > with wire bead is 235g.
> >
> > Were these the blackwall made in Korea Criteriums, or the tanwall made
> > in Japan ones? And what year of production?
>
> They were actually both about 220 g - I'm actually one of those sad
> types who weigh bike parts. The Avocet model was Criterium SL (kevlar
> bead), black side wall, bought last year from Harris Cyclery.
At a guess then, that would mean they rolled off the production line
2-3 years ago. It's interesting that the weight wasn't spec though. I
wonder what the significance is.
> > But note that the thickness of Conti
> > tread rubber drops off very fast as you go away from the centre, unlike
> > Avocets. Is most of your riding in a straight line?
>
> I guess it is, but whose really isn't? I've done my riding in the Alpine
> passes, and even there you're within a few degrees from vertical 99 % of
> the time.
I suppose, unless you are doing much hill climbing while standing. And
hill climbing is where the rear will get the most wear.
> That is why I think the GP 4-Season and also the Ultra GatorSkin are
> both very good tyres for dirt roads or otherwise adverse conditions.
> They have what Continental calls "Duraskin" sidewalls, and I haven't
> heard of anybody having problems with them. If you look at the
> lightweight 23 mm tyres on the market, I think they are definitely
> among the most dependable.
Comparing Conti, Michelin, and Avocet, here you have three different
strategies for sidewall durability:
Conti: 86tpi nylon + an open weave mesh reinforcement, something like
the rip-stops of old rip-stop nylon.
Michelin: 127tpi nylon + an additional bead to bead layer. This doubles
sidewall thickness, and so presumably doubles sidewall toughness and
strength to roughly the equivalent of 63tpi, but increases the
thickness of the under tread layer by only 33%.
Avocet: 127tpi, rayon I believe, with a much more wraparound layer of
thin hard rubber.
Of the three, the Avocet and the Michelin strategies make the most
sense to me, the Conti the least. The old rip-stop nylon was not
particularly effective, and it stopped a rip, instead of preventing its
initiation. The 86tpi + two extra belts under the tread gives great
thickness under the tread, but not as much strength on the sides. So, I
would expect better puncture resistance but less sidewall resistance.
However, Conti is the only one still available in brown sidewalls (at
least some models). A big selling point for me. It seems to me that the
Ultra 2000, with thick carbon rubber and 57tpi sidewalls, is a more
sensible tire than the much more expensive UG or 4-season. However, I
believe they have now discontinued it, of course.
> > The Criterium is not the ideal Avocet tire. I think the R oad, the Duro,
> > and the Duro Plus are where the series really shines.
>
> Could be. I put a pair of Duro K's on my girlfriend's bike, and
> they've been fine and reliable. Avocets are nice tyres, if they're
> available to you at a reasonable price.
The total thickness under tread of the Duro would be roughly 1.15+1.75
=2.9mm, whereas the Criterium would be 1.85mm as previously calculated.
That's close to 60% thicker.
> In Europe, if you want a nice smooth tyre with carbon black rubber, for
> example Michelin Krylion (previously called Carbon) is a great deal.
> According to the rolling resistance tests it's pretty fast, and it has
> a reputation of great mileage an d reliability. Besides, being less than
> 25 euros a piece in mail order, what's not to like?
...how about being $50 apiece mail order in the US? I see sometimes
they are on sale for about $30. They seem good tires but I don't like
the colours (where is my tan or brown?), and then again they only go up
to 25c. I would also rather have the rubber wrap higher up the
sidewalls.
Have you tried Michelin Dynamic? If they had 66tpi casings instead of
33 they'd be close to ideal. But probably even at 33, no one is able to
tell the difference. Too bad they never test them in the mags, they
being too cheap.