Archives mensuelles : septembre 2008

Interbike, first sight


Interbike is the North America’s largest bicycle trade event and show takes place in Las Vegas during 3 days from the 24th to the 26th of September. With over 1,000 of the top brands and
nearly 23,000 attendees from over 60 countries, it is similar to the Eurobike in Europe.
Several manufacturers did keep secret some of their newest products and unveil them at this event.


Ritchey

The giant american manufacturer is updating its wheel range with the Superlogic Carbon Road wheelset, featuring exclusive rims, made with uni-directional, 100 % high-modulus carbon
reinforced with boron. Made by Lew Racing using proprietary DEX-LCM molding process, they combine very light weight, exceptional strength, while being compliant rims.
Hubs are alloy cold forged, made by Ritchey: WCS V3 and V4. Spokes are Aerolite from DT Swiss, 20 front radial, 24 two times crossed rear. The wheelset is claimed to be sub
1100g, at $US2800, including the WCS Ritchey quick releases.


Cervélo

Cervélo releases a newer version of the time trial/triathlon frame. The P4 is claimed to be the fastest ever made bicycle including the UCI legal and UCI illegal bikes. The fork is a custom
Cervélo design making easier the air flow transition with frame, the 570 ml water bottle is right above the bottom bracket and smoothly integrates the down tube, seat tube and bottom
bracket in a single aero form. The rear brake is integrated to the chainstays, thus lowering the air drag and being invisible, it is as powerful as a Dura-Ace caliper, yet being 30%
lighter.

Every single details can be read on Cervélo’s website, or on "http://www.bikeradar.com/news/article/interbike-cervelos-new-p4-storck-gets-stiffer-18706" target="_blank">BikeRadar.


Rotor


Photo ©: James Huang

Already unveiled at the Eurobike, Rotor had the new seatpost visible here too. The SP1 seems cleverly thought to save weight without sacrificing the important reliability. It has an
ovalised interior and smaller diameter as the seatpost exits the seat tube until the head. It weights only 178g in a 27.2 x 350mm size.

The Agilis crank arms can receive an additionnal Quarq-compatible spider to be aware of the power the rider delivers.


Photo ©: James Huang


Chris King

Chris King is well known for its legendary life durable components. This year is an important year for the american manufacturer. Chris King finally releases a new bottom bracket which is
specifically designed for Shimano-compatible external type crank/bottom bracket systems. It features a grease injection tool allowing the bearing to be purged of existing grease and debris
and new run through.
It is available in a wide array of colors.

Chris King also was busy with new hubs: Single Speed road versions, thru axle 10mm and 12mm MTB versions, two 15mm thru axle front options.


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Interbike, premier aperçu


L’Interbike est le plus grand salon nord américain. Il prend place à Las Vegas pendant trois jours: du 24 au 26 Septembre. Avec plus de 1000 marques et environ 23000 participants de plus de
60 pays, cet évenement est similaire à l’Eurobike en europe.
Plusieurs constructeurs ont gardé secret leur derniers composants et les présentent à ce salon.


Ritchey

Le constructeur américain met à jour sa gamme de roues avec les roues Superlogic Carbon Road bénéficiant de jantes exclusives, fabriquées à partir de carbone uni-directionnel, 100%
haut module, et renforcé de bore. Fabriquées par Lew racing à partir du procédé de moulage DEX-LCM, elles combinent un poids très faible avec une exceptionelle résistance, tout en
restant très docile.
Les moyeux sont fabriqués par Ritchey, forgés à froid: WCS V3 et V4. Les rayons sont des Aerolite de DT Swiss, 20 radiaux à l’avant, et 24 croisés à 2 à l’arrière. La paire de roues
est annoncée sous les 1100g, le tarif est de 2800$US, attaches rapides Ritchey WCS comprises.


Cervélo

Cervélo sort la nouvelle version de son cadre de triathlon/contre la montre. Le P4 est annoncé comme le vélo le plus aérodynamique jamais développé, ce qui comprend à la fois les vélos
homologués par l’UCI, et ceux non homologués. La fourche développée par Cervélo facilite la transition du flux d’air vers le cadre, le bidon de 570mm est placé juste au dessus du boîtier de
pédalier et s’adapte parfaitement au tube diagonal, au tube de selle et au boîtier de pédalier dans une forme aérodynamique. Le frein arrière est intégré au bases, ce qui permet de réduire
la traînée et de les rendre invisible, il est aussi puissant qu’un frein Dura-Ace, tout en étant 30% plus léger.

Tous les détails sont sur le  site Cervélo, ou sur "http://www.bikeradar.com/news/article/interbike-cervelos-new-p4-storck-gets-stiffer-18706" target="_blank">BikeRadar.


Rotor


Photo ©: James Huang

Déjà présentées à l’Eurobike, la nouvelle tige de selle Rotor est visible icic aussi. La SP1 semble avoir été intelligemment  pensée pour gagner du poids sans sacrifier la
fiabilité très importante.
L’intérieur est ovalisé et le diamètre extérieur est réduit là où la tige quitte le cadre, jusqu’à la tête. Elle pèse seulement 178g en 27,2 x 350mm.

Les manivelles Agilis peuvent dorénavant recevoir une étoile compatible Quarq pour connaître la puissance développée par le coureur.


Photo ©: James Huang


Chris King

Réputé pour ses composants d’une durabilité légendaire, Chris King met finalement sur la marché un boîtier de pédalier externe, conçu pour les pédalier type Shimano. Les cuvettes
bénéficient d’un outil qui permet de « purger » le roulement de la graisse existante et des débris éventuels, puis d’injecter la graisse propre.
Les cuvettes sont disponibles dans un large spectre de couleurs

Chris King s’est aussi penché sur sa gamme de moyeux: une version Single Speed route pour les vélos « Fixie » à une seule vitesse, des moyeux VTT en axe de 10 et 12mm à l’arrière, et deux
types de 15mm à l’avant.


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Grand test de roues 2008 – Partie 3 – Rigidité

lateral_stiffness_2008_wheels_curve_rear

Tests de rigidité

Photo by Alessandro Trovati

Avec pas mal de retard, nous publions enfin la troisième partie du grand test de roues 2008: celle qui traite donc de leurs rigidités, notions aussi floues que compliquées. Continuer la lecture

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Eurobike: les vélos les plus spéciaux

L’Eurobike 2008 a été très bon. Depuis plusieurs années, la tendance était à alléger les composants, et améliorer l’ergonomie, sans sacrifier la fiabilité. Il semblerait que les limites
soient atteintes avec les standards actuels et les constructeurs ont évolué d’une manière diffèrente.
La nouvelle tendance est à rendre la tâche du cycliste plus facile (cf. le nouveau groupe Shimano électrique), et plus que tout, à rendre les vélos aussi jolis que possible. Beaucoup de
constructeurs proposent plus de couleurs, plus de pièces « à la carte », et c’est une très bonne chose.

Au travers des centaines de stands, seulement une poignée de vélos sortaient du lot et méritaient une attention particulière. De cette poignée de vélos, nous en avons sélectionné seulement
deux: le Parlee de Stefan Behrens, et le Pinarello Prince de Valverde

Le Parlee de Stefan Behrens, Carbon-Sports

Stefan Behrens a offert à son Parlee une nouvelle robe. Le vélo est très spécial, il est entièrement réalisé par un aérographe, le cadre bien sûr, mais toutes les petites
pièces sont aussi peintes dans un thème « à la Cippolini »: un système sanguin parcours les tubes et termine sa course sur les porte-patins!
La somme de travail nécessaire pour réaliser un tel travail est pharaonique, et Stefan n’a même pas été en mesure de nous donner une idée du temps passé par l’aérographe pour peindre ce
vélo.
Ce vélo est probablement celui qui a nécessité le plus de travail de toutes les machines du salon.
Voici les photos:

Le Pinarello Prince d’Alejandro Valverde

Le vélo de Valverde, champion hispanique sur route, était mis en avant sur le stand Pinarello. Il s’agit d’un Prince peint sur-mesure aux couleurs de l’espagne, sur lequel
l’accent a été mis sur les coloris: ensemble cintre/potence peint, freins peints, la signature d’Alejandro, des couleurs bien assorties, etc… Il s’agissait d’un des Pinarello les plus
jolis du stand.

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Eurobike, the most special bikes

Eurobike ’08 was really good. Since a few years, the trend was all about making lighter and lighter components, improving ergonomy, without sacrificing the reliability. It seems like the
limits have been reached with the current standards and the manufacturers needed to evoluate in a different manner.
The new trends are about making easier the cyclists’ tasks (i.e the new Shimano electric), and more than all, making the bicycles as beautiful as possible. A lot of manufacturers tend to
offer more colors, more custom components and that’s a very good thing.

From the hundreds booth, only a couple of bikes were over the pack and we thought they deserved a feature. From these couple of bikes, we only selected two: Stefan Behrens’ Parlee, and
Alejandro Valverde’s Pinarello Prince.

Carbon-Sports, Stefan Behrens’ Parlee

Stefan Behrens had his custom Parlee repainted. The bike is special in several ways, it is entirely airbrushed: the frame of course, but every single components are painted in
a blood system theme! The crankset actually is the hearth of the bike, the veins are running on each part of the bike and even end up on the brake pad holders!
The amount of work involved here is phenomenal and Stefan could even not say how many hours were necessary by the airbrusher to make the whole bike.
The bike is probably the one which required the most work.
Enjoy the pictures.

Alejandro’s Pinarello Prince

Spanish champion Valverde‘s bike was featured on Pinarello‘s stand. Custom painted Prince frame to the spanish colors, it also seemed to involve a high amount of work: painted
bar/stem combo, painted brakes, Alejandro’s signature, well matched colors, it was the nicest Pinarello of the booth.

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Edge Composites 1.24 [en]

The last fall, we featured the Edge Composites rims made in USA (see here). Since this article,
the company based in Ogden extended its rim range: the clincher rims are on the market since a few weeks, and the first flat section rims are being delivered.

« The finish is indeed raw, but keep in mind this is a performance product and we don’t want to paint them or anything that would add weight.« 

Here they are, built with Extralite SX and SR hubs, and 20/24 DT Aerolite spokes. The wheelset is only 861g on the scale, which is not really an argument because a lot of
lightweight and bad wheels are hitting the market nowadays. Knowing the sturdiness of the Edge rims we are testing since a couple of months, to enlarge the incoming range, the
result is much more interesting.
 
 
These 1.24 rims only weight 215g for a depth of 24mm and a width of 21mm, in a triangular section.
The Edge rims finish, serie 1, is very rough, Jake Pantone explains this: « The finish is indeed raw, but keep in mind this is a performance product and we don’t want to
paint them or anything that would add weight.
«  The rims have an unidirectionnal carbon finish, which reminds the newest generation Shimano rims.

The serie number 2 of the Edge rims is differently finished and is stiffer. It is composed of 3K carbon fibre and a clear coat is applied in surface to make it visually perfect.
On the other side, the rims of the serie number 2 are 50g heavier.

The Edge range is now composed of three models: 24mm, 38mm, 68mm. The two last are coming in 1 and 2 version, and in clincher version too.

The rims have no spoke tension limit thanks to the molded spokes holes. So we could easily put 1150N of spoke tension on the drive side of the rear wheel. Basically, this is not
exceptional, but considering the extremely low weight of the components, it is much more exciting.
The spoking is radial front and rear non drive side, it helps saving weight, and increasing the lateral stiffness.
 
Would it be a versatile sub900g wheeset ? We will not claim it. The flat rim do not offer the best aerodynamics, and it is also the weakest of the serie: a deep rim has more material
to flex and resist to the impacts.
Finally, a flat rim needs longer, flexier spokes, so the wheel is also flexier where the lateral load is applied. But the rim also moves less between the brake pads.

The Edge Composites rims descend from the Lew racing fabrications. Several manufacturers did benefit of this construction: Reynolds, Shimano, Easton to quote the most
important. Velonews published an article some months ago about the two american manufacturers. Lew Racing accused Edge of copying a part of the manufacturing process: "http://velonews.com/article/74786" target="_blank">read the article. The pursuits do not seem topical anymore but they reveal the technology the Edge rims beneficiate.

Well these 1.24 rims are under test. If the perform well, we will add them to the boutique.

 

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Edge Composites 1.24

Nous avions mis en avant les jantes Edge Composites fabriquées aux USA à l’automne dernier (voir
ICI
) . Depuis, la compagnie basée à Ogden a développé la gamme de jantes: les versions pneus sont sur le marché depuis plusieurs semaines, et les premières jantes plates viennent
d’être livrées.

« La finition est brute, mais il faut garder à l’esprit que c’est un produit axé performance et nous ne voulons ni les peindre, ni les vernir, ou
ajouter quoi que ce soit qui ajouterait du poids.
« 

Pour le plaisir des yeux, voici donc ces petites dernières, assemblées avec des moyeux Extralite SX et SR, et 20/24 rayons DT Aerolite. La paire affiche seulement 861g sur la
balance, ce n’est bien sûr pas un argument en soi, tant les roues légères et mauvaises fleurissent ces temps-ci. Mais connaissant la robustesse des jantes Edge que nous testons
depuis plusieurs mois en vue d’un élargissement de la gamme à venir, le résultat prend une envergure toute autre.

Ces jantes 1.24 ne pèsent que 215g pour 24mm de hauteur et 21mm de largeur, de section triangulaire.
La finition des jantes Edge, série 1 est hasardeuse, Jake Pantone explique ceci: « La finition est brute, mais il faut garder à l’esprit que c’est un produit axé
performance et nous ne voulons ni les peindre, ni les vernir, ou ajouter quoi que ce soit qui ajouterait du poids.
«   Ces jantes ont donc une finition « carbone
unidirectionnel » qui rappelle fortement les jantes Shimano dernière génération.

La série 2 des jantes Edge est plus axée finition et rigidité. Une couche de carbone 3K et de vernis est ajouté en surface afin d’obtenir un produit parfait visuellement. En revanche, les
jantes prennent un peu plus de 50g au passage.
La gamme Edge s’articule donc sur trois modèles: 24mm, 38mm, 68mm, dont les deux derniers sont déclinés en finition 1 et 2, et en version pneus.

Ces jantes n’ont aucune limite de tension, grâce au trous de jante moulés, plutôt que perçés comme chez la concurrence, donc nous avons pu sans problème, atteindre 1150N sur le côté roue
libre de la roue arrière. Intrinsèquement, ce n’est pas exceptionnel, mais rapporté aux poids des éléments, ces valeurs prennent une autre dimension.
Le rayonnage est radial à l’avant et à l’arrière côté opposé roue libre, gain de poids et de rigidité obligent.

Serait-ce des roues passe-partout sous les 900g?  Nous n’irons pas si loin. La jante plate offre de piètres performances aérodynamiques, elle s’avère aussi la moins résistante de la
série: une jante haute a plus de possibilité de se déformer pour absorber l’impact. Pour finir, une jante plate réclame des rayons plus longs, plus aptes à fléchir, donc la roue s’avère
moins rigide, là où la charge est appliquée. Mais en parallèle, la jante bouge moins entre les patins.

Les jantes Edge Composites sont issue des fabrications Lew racing, dont plusieurs constructeurs ont bénéficié: Reynolds, Shimano, Easton pour ne citer que les plus importants.
Velonews a publié il y a quelques mois un article concernant ces deux fabricants américains, Lew Racing accusait Edge d’avoir copié tout ou une partie du procédé de fabrication:
lire l’article (en anglais, Velonews). Ces poursuites ne semblent plus être d’actualité, mais révèlent le niveau de
technologie dont bénéficient ces jantes.

Bref, ces jantes 1.24 sont en pleine phase de test, et s’ils s’avèrent concluants, les jantes trouveront place dans la boutique.

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Eurobike – 4 – miscellaneous


Look ZED

This is probably one of the most integrated component of the Eurobike. Look definitely pushed the enveloppe with its Zed crankset.
Basically, this component is composed of a single piece of carbon, and a couple of metallic parts. Both arms and the bottom bracket/axle are integrated. Thus, the installation is extremely
easy, we just need to pass one arm through the frame, then lock it with a threaded cup.
It is compatible with both the standard and compact transmissions, the Trilobe adjustement makes the three most usual arm length easy to set, i.e. 170mm – 172,5mm – 175mm
Looks claims it reaches new standards of stiffness, and stiffness to weight ratios.

Xentis

Xentis is releasing a new range of conventionnal wheels. They are based on DTSwiss hubs, and DT Aerolite spokes, and the rims are using a twill carbon weave.
Three rim depth are offered, the three both in clincher and tubular. 25mm, 42mm, 58mm respectively for 1699, 1799, 1899 euros the wheelsets. The weights of the tubular versions are 1050g,
1195g, 1395g, and the clincher versions are 1250g, 1335g, 1535g.
Some prototypes were exposed, they used Tune blue hubs, with a triplet rear pattern.

Deda

Deda Elementi has got some new components for 2009. The range of stems/bars/seatposts is really getting very big and more than all, more interesting than ever.

The Presa is the new full carbon bar. It features extremely short drops (128mm), short reach (77mm). Available in 42-44-46cm from outside to outside. The weight is about 209g. It
features the RHM Rapid Hand Movement concept of Deda, to improve the quick changes of handle position. The Presa is coming in an alloy version too: it is named the Fluida, which is
coming in white and black.
Second, the Nuova Sfida is an aluminium bar wrapped of carbon. It features the RHM too, so the shape is shallow: 75mm reach, 128mm drop. The weight is about 308g.
The Zero100 existed only as a stem, the corresponding handlebar is released: strong 7075T6 triple butted alloy. 40-42-44-46mmcm, drop 128mm, reach 75mm, weight 242g.
Finally, the Fast Black 2 is a time trial aerobar weighting 340g.

Stronglight

The Helion crankset was presented. Here are the real pictures of the crakset:
You can find more informations in the article we published some weeks ago: HERE.

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Eurobike – 2 – Lightweight – DT – Tune – Zipp – Sram

Eurobike, second part on the bike component we appreciate the most, i.e. the wheels.

Lightweight

First, Lightweight the famous wheel manufacturer, updates, or releases new components:
 - the ventoux wheels are generation 3, they receive the full carbon spokes coming with 30% more stiffness
 - the Standard generation 3 rear wheels are available with 24 rear spokes for the most extreme lateral stiffness. Lightweight wanted to beat Mavic with its CCU.
 - the clincher wheels are really available, pressure limit 8 bars, CarbonSports tested the brake track intensively at a well known university in Germany, and needed about 26 wheelsets
that failed to get the perfect reliability, and strength.
 - the rear derailleur is fully available from this Eurobike
 - NEW QUICK RELEASES made out of titanium/aluminium. They weight 32g and are limited to a very high rider weight: 120kg. Carbon-Sports is very confident in the design. 89 euros per
set.
 - Indivudual designs are available for the public. They cost from 250 euros per wheelset beside the normal price of the wheels, to much higher prices. It depends on the work involved
into the airbrush.
 - Last but not least, Carbon-Sports offers an outstanding replacement program: if you add 10% of the wheels cost, you have a « No question asked » replacement during 3 years old!
 
Stefan, CEO of Carbon-Sports worked on an amazing project, based onto airbrush, have a look at it:

DT Swiss

DT updates its spoke and hub line. Most of the new stuffs are for MTB, but the road range is concerned too. First the Aerolite spokes are available in white, as well as the 240s hubs.

Tune

We believed Tune pushed the enveloppe quite much with the Mag130 weighting only 137g. It looks like it is not the only thing, the Mag110 was presented as a prototype too! The rear hub is
112g, sacry, right?
The Mag130 is for sale, and will be available the next summer. It costs 949 euros, equipped of full ceramic bearings.
Well, the white hubs are available too, a new seatpost was presented, as well as new super light skewers and quick releases, based on a carbon axle, bonded aluminium threads, carbon
levers.

THM

Thm definitely has good ideas. The new aero Scapula has a brake integrated. It seems pretty powerful and we are confident into this.

Zipp

Zipp improves its rear wheel with a Mavic like spoking: radial on the drive side, and crossed on the other side. The 255 rims have now there nipples external.
Every wheels receive this upgrade, being Zipp, Flaspoint or Sram.
Several very special looking wheels were presented too.
A new aero crankset, the Vuma Aero was visible too, it is claimed to be reaching new standards of stiffness, while being faster than any competitor.
A new lighter and aero stem was unveiled too. It features inversed bolts, and a dimpled cap.

SRAM

The merge with Zipp allowed SRAM to make wheels. They are pretty similar to Flashpoint Zipp wheels but with different hubs.

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Eurobike – 3 – it continues

X1000

The french company, making the newest full carbon monocoque wheels equips the belgian brand of the legendary champion Yohan Museeuw.
Some of the specifications: 3K carbon fibre, paired spoking, asymetric rear rim, curved rims, oversized full carbon hubs, excellent finish.

American Classic

The american manufacturer improves the rotor of all its hubs, they receive an extra riveted part on 4 splines to block the cassette perfectly in place.
More than all, what changes at AmC this year are the new designs: a coloured spoke is used on each wheel to find the valve hole quicker, and new decals are featured.
Finally, the Magnesium rims won’t be available before a few months because of the difficulties the sub-contractors meets to get the raw material.

Mavic

Beside the CCSLR, the new R-SYS premium, and a full range of comptuter, clothes, and a few more upgrades, Mavic releases new pedals based on a delta style cleat.
Three models are unveiled with titanium and steel axles.
The Race SL Ti features a titanium axle, carbon reinforced plates, a large cleat/pedal contact. it weights 110g per pedal.
The Race is a bit heavier with 130g per pedal, it comes with standard steel axle and composite plate. The Avenir is a step heavier and cheaper too, 145g per pedal.
The cleats are coming in two versions: 0° of float, and 7°.

Powertaps Cosmic Carbone’s are available too. They are quite heavy, the spoking is regular, and is crossed with no contact. Two versions are offered for clincher and tubulars.


Powertap

Saris releases a newer version of the SL powertap. It is upgraded with ceramic bearings and is named Powertap SLC.
10g are saved on this rear hub.

  

Time

Although we already revealed the RXR Ulteam two days ago, we couldn’t resist taking some more shots of this amazing bike.

Canyon

Canyon still produces the F10 featured in the 2007 Eurobike. However, the german company pushes the enveloppe with the Ultimate CF SLX. This new frame is based on the F10 design, but every
single detail is pushed one step further. Lighter/stiffer and more comfortable. We are preparing a complete article about this very special frame, and all the details coming with it.

Beside this road frame, Canyon worked on the newest aero frame which is said to a step faster than the previous version.
 

Tune

We forgot those beauties yesterday. Tune has got lighter than ever quick releases.
19g the set. They feature a carbon axle, carbon levers, and bonded aluminium threads.

  

 

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Eurobike 2008 – 1 – First pictures

Good evening from Friedrichshaefen.
We are happy to unveil the very first pictures of the 2008 Eurobike fair trade.

You will be able to find below the first spied shots of a few manufacturers whose new products definitely interested us.

German Carbon Group

A quick shot at German Carbon Group to present a gorgeous bike, we have found sexy with white/black colors.
Have a look at the newest Scapula aero fork and the fantastic white Clavicula.

Canyon

The newest Ultimate CF SLX, claimed to be lighter and stiffer through several important improvements was equipped with a Record 11s. groupset and Lightweight Generation 3 wheels:

The new time-trial frame was a pure beauty to see, it looks extremely fast, is very thin viewed from the front, which should translate into very high speed.

Storck

Storck is developping a 1755g groupset, which seems to be based on the Micro-Shift taiwanese and cheap groupset. The modifications look dramatic and we hope to see this new system very soon
on the market.
The PowerArms is available for standard and compact transmissions, the touches of blue are pretty on the differents components. The brakes reminds us some weightweenies well known
stuffs…
Finally, the chainrings are made in collaboration with Token.

Beside the groupset, Storck has several components available, such as the handlebars, stems, and seatpost. The touches of blue are visible either on the logos, stickers, either on the
bolts.
They are made by Syntace, and the prices are quite similar: 249 euros the bars, 129 euros the stem, and 149 euros the carbon seatpost.

Of course we had a look at the very beautiful time trial carbon frame. The shapes are so extreme, the blue anodized Zipp hubs were so bling bling, that we didn’t resist to take pictures and
show you the here:

Time

The french manufacturer certainly has one of the most beautiful road frame of the market. The white RXR Ulteam, unveiled this summer, is even nicer with a white paint:

 
 

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Lew Racing Convexo Convex [en]


Convexo Convex. This barbaric name self explains the physical phenomenon Paul Lew, forerunner in bicycle wheels world, relied on for his newest invention. This time-trial disc wheel differs
from the others by its shape, which converges on the rear, and features the swirl lip generator reducing the crosswind sensivity.
The tests performed in a windtunnel, proved this double convex disc wheel to optimize the aerodynamic of the rider plus bike system: it reduces the drag, so the power needed to ride at a
given speed.

Convexo Convex

In theory

This wheel pushes the limit of the disc design to a new standard. Where the flat sided disc wheels create a lot of turbulences, a lens shaped disc wheel, by its curved shape on the non
drive side, reduces the drag by making easier the perturbated air flow.
Nevertheless, according to the manufacturer, this construction sees its limits: the wheel behaves as an aircraft wing because its curved shape on a side, and flat shape on the other creates
a pressure difference on each side, meaning extra drag.

« For a minimal drag, the perturbated air flow must converge behind the rider« , Paul Lew told us.

This is here this wheel differs from the others, the Convexo Convex is curved on both sides. This special shape helps the air flow, perturbated by the presence of the rider and its bike, to
stick the wheel and leave the system clearly. Obviously the speed, the bike shape, and the rider position significantly modify these drawings.

On the right, the flat sided ovoïd rim disc wheel, such as a Zipp Sub9, has the airflow perturbated behind it because of the flat flanges.

On the left, the airflow of the Convexo Convex wheel converges and leaves the system as a clear flow, synonym of low drag, so better aerodynamic properties.

In practise

The tests performed at Mooresville, North Carolina, USA, recorded thousands datas. The wheels claimed to be the fastest of the market were tested on the bench.
The drags are recorded for the wheels only, and more interesting, for the wheels installed on the bike, including a rider. The position of the rider is kept thanks to several markers.

The results are summarized in the table below:

Wheels only Drag (g), yaw 10° (error +/- 0,5%)
Zipp 404 front 157
Lew Pro VT1 front 177
Zipp Sub9 75
Lew Convexo Convex 115

Regarding the wheels only, Zipp is indeed the fastest: 12% less drag for the front wheel, and 53% less drag for the rear wheel! The difference is significant and corroborates the datas
claimed by Zipp, constantly improving the aerodynamics on its wheels.
Yet, testing a wheel alone is not really accurate to predict the results of a complete system rider/bike. Lew Racing thus pushed the tests further to know what happens with a world class
rider and its Cervelo P3C.
The results are very different, and sometimes advantage the Lew configuration, sometimes the Zipp:

Configuration Bike + racer + wheels Drag (g), yaw 10°, (error +/- 0,5%), average of 2 run Drag (g), yaw 20°, (error +/- 0,5%), average of two runs
1 Zipp 404 front / Zipp Sub9 rear 1820 1594
2 Zipp 404 front / Lew Convexo Convex rear 1767 1665
3 Lew Pro VT1 front / Lew Convexo Convex rear 1811 1586

A few points are important here: with a yaw angle of 10°, the Zipp404/Zipp Sub9 configuration is as fast as the Lew Pro VT-1/Convexo Convex, taking into account the measure errors.
When comparing the configuration 1 and 2, only the rear wheels change. The fastest configuration is the one mixing the 404 front, and the Convexo Convex rear. The fastest rear wheel at 10°
is the Lew.

At yaw 20°, the configurations « full » Zipp or « full » Lew are as fast, when taking into account the errors. Weirdly the fastest configuration at 10° is the slowest at 20°.
At this angle, the configuration 1 is faster than the number 2. So the Zipp Sub 9 is faster than the Convexo Convex. However, the configuration 3, which is the « full » Lew, is as fast as the
« full » Zipp configuration!
It shows how difficult it is to predict the aerodynamics of a system. It also means testing a wheel only is not the best idea for a complete system…

Only Zipp wheels, among the current fastest wheels have face the Lew in this test.
The results can be downloaded here.

What’s on the scale?

Of course, as every products coming from the Lew factories, the components are extremely light. The carbon and boron wheel, lens shape, is 780g. As comparizon, the Lightweight Disc, flat
sided, is 800g, the Zipp Sub9, flat sided with ovoid rim, are 1000g, the Corima flat sided are 1060g, and finally, the Mavic Comete flat sided/lens shape is 1285g.

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Lew Racing Convexo Convex


Convexo Convex. Un nom barbare qui explique à lui seul le phénomène physique sur lequel s’est appuyé Paul Lew, précurseur dans le monde de la roue, pour sa dernière invention. Cette roue de
contre-la-montre diffère des autres par sa forme, qui converge en sortie, et reprend le concept mis en place sur la jante Pro VT-1, à savoir le petit épaulement qui réduit la sensibilité de
la roue aux vents latéraux. Les tests effectués en soufflerie, ont montré que cette roue lenticulaire permet d’optimiser l’aérodynamisme de l’ensemble coureur plus machine: réduction de la
traînée, donc la puissance à fournir pour une vitesse donnée.

Convexo Convex



En théorie

Cette roue pleine met donc en avant le concept de la roue lenticulaire poussé à l’extrême. Là où une roue paraculaire est parfaitement plane et crée beaucoup de turbulences, une roue
lenticulaire, de par sa forme bombée d’un côté, réduit la traînée en facilitant l’écoulement du flux d’air, déjà perturbé, derrière le coureur. Cependant, d’après le constructeur, cette
construction voit ses limites apparaître assez rapidement: la roue agit comme une aile d’avion car la forme bombée d’un côté et plane de l’autre crée une diffèrence de pression de chaque
côté, synonyme de traînée supplémentaire.

« Pour une traînée minimale, le flux d’air perturbé par le coureur doit converger en sortie » nous confie Paul Lew.

C’est à ce niveau que cette roue fait la diffèrence avec d’autres, la Convexo Convex est bombée des deux côtés. La forme spécifique de la roue permet au flux d’air perturbé par la présence
du coureur et du vélo, de venir « recoller » à la roue en sortie. Le croquis théorique sur la droite met en évidence le phénomène. Il est évident que la vitesse, le type de vélo et la
position du coureur modifient singulièrement ces croquis.

Sur la droite, la roue paraculaire avec jante ovoïde, type Zipp Sub9, voit le flux d’air perturbé en sortie à cause du flasque plat.

Sur la gauche, le flux d’air de la roue Convexo Convex converge et sort en un flux unique synonyme de faible traînée, donc d’un meilleur aérodynamisme.

En pratique

Sur les tests mis en place à Mooresville, en Caroline du Nord, USA, une multitude de valeurs sont enregistrées. Plusieurs roues, celles censées être les plus rapides à l’heure actuelle,
sont passées sur le banc.
Les traînées sont enregistrées pour les roues seules, et, plus intéressant, pour les roues installées sur le vélo, coureur positionné. La position du coureur est conservée grâce à plusieurs
marqueurs.

Nous vous résumons donc les résultats les plus intéressants concernant les roues seules dans le tableau ci-dessous:

Roues seules Traînée (g), angle 10° (erreur +/- 0,5%)
Zipp 404 avant 157
Lew Pro VT1 avant 177
Zipp Sub9 75
Lew Convexo Convex 115

En ce qui concerne les roues seules, Zipp est bien le plus rapide: 12% de traînée en moins sur la roue avant, et 53% sur la roue arrière! La diffèrence est assez significative et corrobore
les données annoncées par Zipp, toujours à la pointe de la dernière astuce lui permettant de rendre ses composants un peu plus économes en énergie.
Cependant, ne tester qu’une roue seule n’est pas suffisamment précis pour pouvoir prédire les résultats sur un système complet coureur/vélo. Lew Racing a donc poussé les tests un peu plus
loin en vérifiant les résultats avec un coureur de niveau mondial sur son Cervélo P3C.
Les résultats sont totalement diffèrents, et avantagent tantôt la configuration Lew, tantôt à la Zipp:

Configuration Vélo + coureur + roues Traînée (g), angle 10°, (erreur +/- 0,5%), moyenne de deux essais Traînée (g), angle 20°, (erreur +/- 0,5%), moyenne de deux essais
1 Zipp 404 avant / Zipp Sub9 arrière 1820 1594
2 Zipp 404 avant / Lew Convexo Convex arrière 1767 1665
3 Lew Pro VT1 avant / Lew Convexo Convex arrière 1811 1586

Plusieurs points sont importants sur ce tableau: sur un angle d’attaque du vent de 10°, la configurations basée sur du Zipp404/Zipp Sub9 fait jeu égal avec la configuration Lew Pro
VT-1/Convexo Convex, aux erreurs de mesure près.
Si l’on compare les configuration 1 et 2, seules les roues arrière changent. La configuration la plus rapide étant celle mixant la 404 à l’avant, et la Convexo Convex à l’arrière, la roue
pleine la plus rapide est donc la Lew, à 10°.

A 20°, les configurations « full » Zipp ou « full » Lew font jeu égal, aux erreurs de mesure près. Etrangement la configuration la plus rapide à 10° s’avère être la plus mauvaise à 20°.
Sous cet angle de 20°, la configuration 1 est plus rapide que la 2, donc la Zipp Sub9 est plus rapide que la Convexo Convex. Cependant, la configuration 3, basée sur une Lew Pro VT1 à
l’avant, est aussi rapide que la configuration basée entièrement sur du Zipp!
Preuve qu’en aérodynamisme les règles sont difficilement prédictibles, et preuve aussi que tester une roue seule s’avère être une mauvaise idée par rapport au système complet…

Seules les roues Zipp, parmies les plus aérodynamiques à l’heure actuelle, ont fait face aux Lew dans ce test.
Les résultats complets sont consultables via ce PDF.

Et la balance?

Evidemment, comme tous les produits sortant des usines Lew, les pièces sont extrêmement légères. La roue, de carbone et de bore vêtue, lenticulaire, atteint les 780g. A titre de
comparaison, les Lightweight Disc paraculaire pèsent 800g, les Zipp Sub9 paraculaire à jante ovoïde affichent 1000g sur la balance, les Corima paraculaires 1060g, et pour finir, les Mavic
Comete paraculaires/lenticulaires 1285g.

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Extralite UltraRear SX – Tune 2009 [en]

Extralite 2009

Extralite released the front SX hub some months ago. The italian company is now unveiling the rear version. Straight pull spokes and J bent spokes will be required to build this
lighter than ever rear hub.
As stock components, Extralite offers a hubset weighting in only 183g, 49g the front, and 134 the rear, which is the weight of a very light rear hub, such as the Tune Mag180 (185g) or DT190
Ceramic (192g).
Before building Extralite hubs, we wondered how it was possible to make so light aluminium hubs: the stock Extralite SR is 155g, without losing resistance, nor reliability…

It was obvious after disassembling an SR hub. First, the diameter of the axles of these super light rear hubs is multishaped: between 15 and 17mm. Second, the bearings are pretty big: 6803
and 6804, which is very rare on stock wheels. Third, the hub shell to rotor junction is running through two « plastic » discs, sliding onto each other, which is pretty similar to what Mavic
uses. Last but not least, the play setting is done by hand with the micro-tuner, a knurled plastic bolt. So light, easy and efficient!
The Extralite rear hubs are, from our point of view, extremely well designed.

However, although being ultra light and reliable, they will obviously remain less durable than most heavier competitor hubs. There are at least two causes:
- the two plastic discs sliding onto each other should, in theory, wear faster than a complete bearing. At Tune, this junction is realized by a double bearing, based on a 6802/6902
whose internal race is similar.
On a high end DTSwiss, this junction features two extremely resistant « ratchets », and two springs pushing them against each other.
- Then, the Extralite rotors only have 2 engagement pawls, which are quite thin, to transfer the torque to the hub shell. As comparizon, Tune uses 3, PMP too. Regarding the biggest
wheel manufacturers, Campagnolo equips its freewheels with 3 pawls, Mavic only two, but those are quite wide.

Regarding the design, the Extralite UltraRear SX requires straight pull spokes on the drive side, and standard J bent spokes on the non drive side. Why? Extralite claims a better stiffness
and reactivity. We will keep in mind removing the axle is not required anymore to lace the radial spokes of the non drive side.
The geometry is optimized for Shimano: the right side end nut is shorter than the Campagnolo one, and allows wider bracing angles, thus a stiffness gain.

From a weight point of view, this hub is claimed to be between 134 and 136g depending on the drilling. We are waiting for the first model to test and eventually offer them in the boutique
if we are satisfied.

Extralite range

Front hub Rear hub
Model UltraFront SX UltraFront SL UltraFront SP UltraRear SR UltraRear SP UltraRear SX
Material AL7075TX & GRD5 Titanium AL7075TX & GRD5 Titanium AL7075TX & GRD5 Titanium AL7075TX & GRD5 Titanium AL7075TX & GRD5 Titanium AL7075TX & GRD5 Titanium
Spoking J-bent spokes Straight pull spokes Straight pull spokes J-bent spokes Straight pull spokes Straight pull spokes/J-bent spokes
Bearings 2×6801 2×6803 2×6801 2×6803/6804 2×6803/6804 2×6803/6903
Axle 14mm 17mm 14mm 20/17mm 20/17mm 17mm
Weight 49g 62g 49g 155g 150g 134g
Price 149 euros 149 euros 149 euros 349 euros 389 euros 399 euros


Tune 2009

Some informations about Tune 2009 were unveiled on our fellow member Light-bikes.de website. The main news concern the MTB hubs with the X12 system allowing very easy wheels installations/
A new color will be added to the already very wide color range at Tune: red/blue/black/silver/pink/orange/green!
The Mag140 which was under development since two years old is finally added to the catalog. It will keep the shape of the Mag150, current high end rear hub, but with a couple of
upgrades to save a few grams.
A new prototype is under development. It is also based on the Mag150 design, but it pushes further the limits. 137g …
We invit you to have a look at the german website for more information.



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