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یکشنبه 20 دی 1394 :: نویسنده : sajjad m

Tested: SRAM GX 1x11 Mountain Bike Drivetrain

1x takes one more step toward being a basic human right

JANUARY 6, 2016
SRAM GX Drivetrain
THE SRAM GX 1X DRIVETRAIN IS ALMOST IDENTICAL TO SRAM'S HIGHER-END X1 AND X01 GROUPS, PRIMARILY DIFFERING IN MATERIALS AND MANUFACTURING.
Photograph By Jonathan Pushnik

Although SRAM has steadily trickled down the technology from its top-of-the-line, XX1 one-by-eleven (1x11) mountain group since 2012, a 1x drivetrain—a single chainring with a wide-range cassette to provide a similar gear range to a 2x system—was still a premium offering unless you wanted to hack it with a conversion kit. But when SRAM released its GX group last spring, it slashed the minimum buy-in to $564, and as low as $3,500 for a complete bike with GX. And just like that, more of us could dream of one day owning a clean-looking bike with simpler shifting and more handlebar real estate.


GX is almost identical to SRAM's higher-end X1 and X01 groups, primarily differing in materials and manufacturing. The biggest saving: The X01 and XX1 10-42 cassettes are machined from a single piece of steel, while the GX version is held together by stainless steel pins. More affordable materials are also used in the crankset, crankarms, chain, and the derailleur—which otherwise share the same features as their X1/X01 counterparts. The weight penalty: 221 grams over the $1,335 X01 group.

    RELATED: Should You Get a 1x Drivetrain on Your Road Bike?

Tested on my Scott Contessa Genius 710, GX shifting felt clean and responded to the same light, quick touch as its premium counterparts. When the terrain really undulated and I was toggling gears often, the shifting was just slightly less refined compared with the X1/X01-equipped bike I'd also been recently riding. But GX was still accurate and reliable, and I could swiftly dump two to three gears when needed. Thederailleur is designed to keep the chain taut and quiet, and it does, and the chainring's alternating narrow and wide teeth prevent chain drop. GX is compatible with SRAM's higher-end 1x11 groups so you can save on replacement parts. And it's also available as a 2x with the 10-42 cassettefor a monstrous gear range.

I recently lent the GX bike to another editor. Afterward, I asked for her impression of the shifting. She shrugged, "It was good. I never would have thought about it if you hadn't asked." Changing gears on the trail should always be such a nonissue. And now it can be for more of us.

Price: $564, as tested
Weight: 1,831g






نوع مطلب : امروز در جهان - cycling in the world، قطعات دوچرخهbike parts، دانش ساخت دوچرخه، 
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Chris Froome was one tough customer at this year's Tour amid an onslaught of attacks both on and off the bike.

Maybe it was the vitriol coming from media and cycling fans, or maybe the wayward bottle that Vincenzo Nibali totally didn’t throw at him. More likely it was a combination of it all. Regardless, this was the year Chris Froome dropped the nice-guy routine.

After stage 6 of this year’s Tour de France, it was clear we were dealing with a different Froome. That’s when, after feeling that Nibali had flung a bidon at him, he rode to the Astana team bus, handed his bike to a staffer, and forced his way on to confront the Italian. Later in the race, when Froome got in Nibali’s face over what he felt was an unsportsmanlike attack in stage 19, Nibali told reporters, “I don’t deserve the words he said. They are too hard, and not right to say.”

Froome addressed his tougher demeanor during a Tour press conference. “I try to be as polite as possible,” he said. “But don’t take that for weakness. Don’t take that as you can push me around, or that you can get away with disrespecting me or my teammates. I will stand up for what I believe in.”

Froome had to stand up to more than just Nibali. For starters, there was what was widely accepted to be one of the most brutal Tour routes in recent memory. He had even suggested he might skip it, as he felt it was too heavy on climbs and too light on time trials. But instead, he deemphasized time trialing and doubled down on his climbing skills, which he unleashed with an attack on stage 10 to La Pierre-Saint-Martin that rendered fellow pre-race favorites like Nibali, Nairo Quintana, and Alberto Contador little more than collateral damage.

So dominant was his stage 10 ride, Froome’s Team Sky released his power data in hopes of silencing the critics. It didn’t work. From that point on, Froome became the focal point of countless people’s frustrations with pro cycling. “Experts” presented his power data as evidence of doping. The masses on Twitter found new ways to cram accusations into 140 characters. And roadside spectators in France went from annoying (shouting “doper” in Froome’s ear) to gross (spitting on him) to grosser (hurling urine at him).

He withstood it all and won. So go ahead and make fun of his form on the bike, just don’t do it to his face. As Froome showed us this year, he’s one tough dude.

Honorable mention: Fabian Cancellara

If Chris Froome has the figurative backbone of the year, Fabian Cancellara has the actual one. His summertime return from a broken back was derailed when he went over the handlebars at the Tour — while wearing yellow — and broke his back. One broken back in a lifetime would convince most of us to take it easy. A second one would have us taking up quilting. But Spartacus was back racing at the Vuelta, before a virus put an end to his season. Here’s hoping he finds a way in his final pro season to make all the pain worthwhile.


Read more at http://velonews.competitor.com/2016/01/news/road/2015-velo-awards-chris-froomes-got-backbone_391626#owuuXomoB1BIvua4.99




نوع مطلب : امروز در جهان - cycling in the world، 
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نوع مطلب : افتخاراتmakibike production، امروز در جهان - cycling in the world، دانش ساخت دوچرخه، 
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سه شنبه 15 دی 1394 :: نویسنده : sajjad m

Germany Opens Bicycle-Only Autobahn

The route will eventually include more than 60 miles of bike highway, and could take 50,000 cars off the streets each day

5
German Bicycle Autobahn
THE NEW PATH SHOULD TAKE AS MANY AS 50,000 CARS OFF THE ROAD EACH DAY, ANALYSTS PREDICT. 
Photograph By PATRIK STOLLARZ/AFP/Getty Images

It's every cyclist's dream: no red lights, no trucks, just a clear, smooth lane to zoom down with the wind in your face. Welcome to Germany's first bicycle Autobahn. Fans hail the smooth new velo routes as the answer to urban traffic jams and air pollution, and a way to safely get nine-to-fivers outdoors.

As a glimpse of a greener urban transport future, Germany has just opened the first three-mile stretch of a bicycle highway that is set to span over 60 miles. It will connect 10 western cities including Duisburg, Bochum, and Hamm and four universities, running largely along disused railroad tracks in the crumbling Ruhr industrial region. Almost two million people live within 1.2 miles of the route and will be able to use sections for their daily commutes, said Martin Toennes of regional development group RVR.


Aided by booming demand for electric bikes, which take the sting out of uphill sections, the new track should take 50,000 cars off the roads every day, an RVR study predicts.

The idea, pioneered in the Netherlands and Denmark, is gaining traction elsewhere in Germany too. The banking centre of Frankfurt is planning a 18-mile path south to Darmstadt, the Bavarian capital of Munich is plotting a 9-mile route into its northern suburbs, and Nuremberg has launched a feasibility study into a track linking it with four cities. In the capital Berlin, the city administration in early December gave the green light to a feasibility study on connecting the city centre with the leafy southwestern suburb of Zehlendorf.

The new velo routes are a luxury upgrade from the aging single-lane bike paths common in many German cities, where tree roots below can create irregular speed bumps and a mellow cycling lane can suddenly end or, more alarmingly, merge into a bus lane. The new type of bike routes are around 13 feet wide, have overtaking lanes and usually cross roads via overpasses and underpasses. The paths are lit and cleared of snow in winter.

Like most infrastructure projects, the bicycle Autobahn is facing headwinds, however, especially when it comes to financing. In Germany, the situation is complicated because while the federal government generally builds and maintains motor-, rail-, and waterways, cycling infrastructure is the responsibility of local authorities. For the Ruhr region's initial five-kilometre rapid track, the cost was shared, with the European Union funding half, North Rhine-Westphalia state coughing up 30 percent, and the RVR investing 20 percent. Toennes said talks are ongoing to rustle up 180 million euros ($196 million) for the entire 60-mile route, with the state government, run by center-left Social Democrats and the Greens party, planning legislation to take the burden off municipalities. "Without (state) support, the project would have no chance," said Toennes, pointing to the financial difficulties many local governments would have in paying for maintenance, lighting and snow clearance.

In Berlin, a heavily indebted city-state, the conservative CDU party has proposed a private financing model based in part on advertising along the route. "The bike highways are new in Germany," said Birgit Kastrup, in charge of the Munich project. "We must find a new concept for funding them."

The German Bicycle Club ADFC argues that, since about 10 percent of trips in the country are now done by bicycle, cycling infrastructure should get at least 10 percent of federal transport funding. "Building highways in cities is a life-threatening recipe from the 1960s," said its manager Burkhard Stork. "No one wants more cars in cities."





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