lunes, septiembre 06, 2010

Shimano XTR for 2011


race group


August 23/10 19:49 pm - Shimano XTR for 2011


Posted by Editoress on 08/23/10


After spending much of the season writing about and taking photographs of riders using Shimano's new fifth-generation flagship offroad XTR group, I had the opportunity to try it myself during the press launch held for selected publications earlier this month. After flying into Reno, Nevada, Shimano's Devin Walton picked up a group of us for an hour's drive west into California's Tahoe region.



Photo gallery



The Lakes Basin area where we were based, near the town of Graeagle, is, in my opinion, due to become one of the next great mountain bike riding Meccas. Local mountain bike and hiking groups are working with the Parks department to create a staggering network of trails through the Sierra Nevada mountains. Downieville, home to the rapidly becoming famous Downieville Classic, is but one of the towns that welcomes mountain bikers. Put this on your To Ride list...



scenic



Shimano made the extremely bright decision of letting XTR speak for itself, rather than having us spend most of our time sitting in a conference room, watching slideshows and wishing we were riding... Two short sessions (one each day) were spent introducing us to the new group, and the rest of the time spent riding (except for the evening spent on a copy of the SS Minnow floating around Lake Tahoe having dinner, but that's another story...). We took two extende rides - the first a cross-country and very technical jaunt through the alpine terrain around Golden Lake outside of Graeagle, and the second on the 17 mile (28 kilometre) downhill that makes up the Downieville Classic route.

So, what has changed in XTR for the fifth generation? The answer is: pretty much everything.




For starters, there isn't just one XTR anymore, instead there is Race and Trail. The philosophy behind the split is that not only racers want XTR's extreme durability, shifting performance, etc. There are lots of multi-day racers, all day/all mountain riders and the like who also want top-line componentry. Even more, there are racers who want some rugged components to go along with the lighter weight stuff, and some bigger hit riders who want to mix in some light weight components.






As Shimano puts it, "Riding Everywhere, Riding Everything".

This has led to the development of a menu of XTR components for the Race and Trail side, which allows a rider to mix and match, and create their ideal set up. Want full on race with heavier duty braking? Check. Or maybe a trail bike that uses a 2x10? Check.

Overall, the new XTR can save anywhere from 50 grams (full Trail without wheels and pedals) up to an impressive 400 grams (full Race with wheels and pedals), depending upon the set up. Shimano was unable to provide prices, but promised that it would be no more expensive than previous groups. Availability is October (both aftermarket and on bikes).

My test group was fitted to a 2011 Norco Range, that the people at Norco graciously donated (see our Range review from the Norco 2011 launch here). The bike will be shipped to us for a long term review, so we can provide follow up remarks as different testers ride it under varying conditions (Graeagle offered only extreme dust...).
http://www.canadiancyclist.com/reviews.php?id=19668

Onto the specifics...

Drivetrain

The Trail version of XTR was designed for riding faster with control, while Race is more about efficiency and weight. Both versions use the newly introduced Dyna-Sys ten-speed drivetrain, first introduced on XT and SLX. Dyna-Sys stands for Dynamic Drivetrain System, and represents Shimano's latest efforts to improve drivetrain function and efficiency.DBL crank

It has been optimized for the Shadow style of derailleur, and is centered around wider range gearing at the rear and narrow range at the front. So, for example, Dyna-Sys uses a 32 front middle chainring with a 36 rear cog, to give you the same ratio of the more traditional 22 front / 26 rear. Shimano claims that one of the things this does is reduce chain tension and thus less energy is lost in the suspension when pedaling. A secondary benefit is that the shifts from the middle ring to the granny are smaller, and therefore there is less loss of cadence.

The standard set up is a triple (42/32/24), but a variety of double options are also available: 44/30, 42/30 and 40/28. A final option - mainly for Trail use, or 29ers - is the 38/26. Except for the latter (38/26), the doubles have a dedicated crank arm, so you can't switch back and forth between a double and a triple set up.

The ten speed cogsets are available in 11-34 and 11-36, and feature five titanium cogs, a three-piece spider body for mounting and tooth profile to optimize shifting performance.

The front derailleur is available in multiple mounting styles to fit almost any frame design (separate ones for double and triple), while the rear derailleur has been redesigned to make it more linear in shifting force (and less effort).

The shifters will work for either 2x10 or 3x10 (an easy adjustment), and riders can shift either one cog or grab a handful in one shift. The levers have also been designed for two-way release, so that they can be actuated by either finger or thumb - a cool touch. The levers also have anti-slip dimples.

chain



The final drivetrain change for Gen-5 of XTR is a dedicated chain (above); the HG-X. It is an asymmetrical design, with the outer plate optimized for front shifts and the inner for rear shifting, to take into account where the greatest shifting forces take place in each case. Shimano clearly stressed that it is NOT the same as the Dura ace chain, with completely a different plate design. It is a directional chain, and has been optimized for avoiding mud build up.

That covers all the tech aspects of the drivetrain, so what about actual use? XTR was already one of the best shifting systems on the market, in my opinion, so the enhancements in this area only improved upon an already strong system.

The anti-slip dimples are a very nice touch, and make a noticable difference. Shifting was consistently good, even under pressure on rocky inclines. I will agree that the Dyna-Sys shifting pattern is intuitively better - just make one shift front or back to get the next gear ratio. I found as riding went on, I was able to find the most appropriate gear for any situation more quickly than usual, even if the terrain changed suddenly. Shimano calls this VIVID Index, I just call it being confident that I can make shifts whenever I need them.

Brakes

Back at the Mountain Bike Nationals, I asked Geoff Kabush (Maxxis-Rocky Mountain) for his take on the new XTR, since he had just finished BC Bike Race and had won the Nationals on it. His greatest praise was directed at the brakes, and I would definitely agree.

XTR has been a fine braking system in the past, but no better or worse than a bunch of others. With the new XTR ICE Tech technology, Shimano has set a new standard for off road braking. Once again, there are Race and Trail versions, but I would have a hard time recommending anything but Trail - the marginal weight difference is vastly outweighed by the anti-fade capabilities of the more robust system.

The Race version has a 10% increase in power (from the previous generation), according to Shimano, while Trail is up 25%. Trail comes with servo-wave levers and Race does not (weight saving), Trail comes with finned, stainless steel-backed pads, while Race comes with a standard resin (again, weight saving).

Both come with the same forged brake caliper and oversized ceramic piston for heat dispersal, as well as a redesigned rotor that uses an aluminum core and stainless steel outer. Together, Shimano claims this allows the brakes to heat up a full third more than before without any brake fade. The ICE Tech finned pads improve heat resistance even further, and are said to be better in the mud and wet (we haven't had a chance to test this yet).

So, why would anyone use the composite pads? Well, besides the weight savings, Shimano says they don't have the same wear-in period, are less noisy and more responsive in the dry. Unfortunately, they also wear out considerably faster.

On long sections of descending on the Downieville course there was no noticable brake fade at all. Brake feel was very smooth and consistent no matter how tightly you hauled on the levers. Modulation remains exceptionally good.

Very, very impressive.

Wheels

As you would expect, there are considerable differences between Race and Trail wheelsets. Both are tubeless, with narrower rims and smaller gauge spokes on the Race version. The hubs use angular contact bearings, and Shimano says that each set of hubs and bearings is laser matched for smoothness and precision. The Race wheels come with Scandium rims and weigh in at 1480 grams for the pair. The Trail ones are 1670 grams with a quick release rear hub, and 30 grams more with a 12mm thru-axle. The front Trail is E-through compatible.

Pedals

One of the complaints about Shimano's competition pedals has been how little support they offer, because of the small footprint (no pun intended). Shimano has been listening, and has responded with two new versions, both of which provide more support. The old style SPDS offered 60.6 square millimetres of surface area, while the new Race are up to 226.9 sq. mm and the Trail a whopping 585 sq. mm.



pedal



Shimano did this by making a wider body on the same length spindle, as well as making the pedals lower profile. The Race version is similar in appearance to the older model, while Trail version comes with an aluminum body that extends out back and front for extra support. Both have mechanisms that Shimano claims are better at shedding mud (no on-bike experience with that yet). The Race weigh in a 310 grams/pair, approximately 90 grams more for Trail.

One note of caution - both Race and Trail (but especially Trail) are considerably lower profile than the previous editions and, coupled with the wider body, a number of us who were on non-Shimano shoes found that it was difficult to clip in if the cleat was recessed at all (ie, shoe lugs were built up on the sides of the shoe). Specialized shoes seemed to have a particular problem. Shimano engineers from Japan were busy muttering and scribbling notes when they saw this.

Pretty much everyone present wanted to stick with Trail pedals once they had tried them, and if you don't buy anything else from the XTR group, this would be one worthy upgrade.

Conclusions

XTR has always been reliable, durable and user-friendly. The new XTR shows that Shimano is not resting on their laurels, and is serious about maintaining their status as the best all around mountain biking group.

Our thanks to Shimano Canada for allowing us to participate in this session.
gallery
http://www.canadiancyclist.com/races10/XTR/index.htm

http://www.canadiancyclist.com/dailynews.php?id=19948

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