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Used to be that if you wanted to buy Shimano’s best cross-country race components, you’d just look for the XTR label. Not anymore—not exactly, anyway. For 2011, Shimano has expanded the XTR name to cover a family of top-end components that allow buyers to choose between ubber-light Race components and the more robust but still light Trail parts, all with 10-speed cassettes that let riders choose between 3×10 or 2×10 setups.

They all work together, too, so buyers can mix and match to create their perfect bike. A rider who frequents rough terrain but doesn’t do a lot of sustained descents might opt for a Race setup but with XTR Trail wheels. A 180lb racer might choose to put bigger Trail brakes on an otherwise all-Race bike. And even with the move to 10-speed cassettes—the centerpiece technology, called Dyna-Sys, of Shimano’s new mountain groups—XTR saves 200 grams over the older version in the Race configuration and, more startling, 50 grams in the beefier Trail setup.

The correct XTR choice for most riders will be the Trail configuration. To launch the group, Shimano invited several journalists to Graeagle, California, near Lake Tahoe, for two days of heavy trail riding that included sustained climbs and a run down the 5,000-foot Downieville Classic downhill course. Where better to test the real-world versatility of Shimano’s new 10-speed cassette and completely redesigned hydraulic brakes?

Drivetrain

My first impressions are that, as I’ve already noted with SRAM’s 10-speed cassettes, the addition of an extra cog on the cassette isn’t just a marketing ploy. For SRAM, it has meant a rethinking of cranksets and front derailleurs and a big push for two-chainring systems. For Shimano, it means wider gear ranges and, thus, fewer front shifts, with three-chainring setups.

The 36-tooth big cog on my XTR test cassette probably resulted in at least a third fewer front shifts than I would make with a 3×9. On steeper pitches where I would normally want to drop into the small chainring, the 36 was just easy enough to let me stay in the middle chainring. Fewer front shifts means fewer distractions and fewer dropped or broken chains.

Also, since most mountain biking happens in the middle chainring, rear suspensions are often designed to work best in this chain position. So, theoretically, the middle is where you get the best suspension performance. Though 2×10 setups can be lighter, narrower, and mechanically simpler, they lose that natural position up front and thus require more frequent front shifts. Dyna-Sys breathes new life into the middle chainring of a triple. However, the triple is still plagued by cross-chaining issues that the milder chainlines of a true double avoid.

When front shifting is needed, Shimano remains best in class. The two-piece, Hollowtech chainrings are remarkably stiff. And the wider rear gearing has enabled Shimano to reduce the jumps between front chainrings (42, 32, and 24 teeth on the triple), which only adds to the precision and also results in a more progressive gearing changes with front shifts.

Rear shifting, which was already solid in old-generation XTR, is markedly better. Shifts are more precise and responsive, even under power. Shimano says this is due to the redesigned rear derailleur, which requires less cable tension, and also to the directional, 10-speed-specific chain. The four plates in each link in the new chains each have a different design that lets them interact with the shift ramps and pins on the cogs in different ways. The overall result is the best-shifting XTR group ever.

The shifters, too, are redesigned, with longer levers and dimpled surfaces for better control and grip. Fans of Shimano’s two-way shift levers and multiple-shift throws will be happy to know that both have carried over into the new group.

Brakes

Shimano also completely redesigned the XTR brakes, which will offer XC Race and Trail options. Our Trail brakes had much better top-end bite than previous XTR brakes (Shimano claims the Trail brakes are 40 percent more powerful, while the Race brakes offer a 10 percent boost, relative to old-gen XTR).

Innovations include a lever-pivot that increases the leverage ratio for more bite at the end of the stroke, “Ice Tech” cooling fins on the brake pads to dissipate heat (brilliant), and three-layer rotors that have an aluminum core for further heat dissipation. The Race brakes wont have the variable-rate levers (called Servo Wave) or the Ice Tech pads, though the latter will be an after-market option.

Pedals

The much beloved XTR pedals also get a redesign for 2011—two redesigns, actually, as they, too, will now be available in a Race or Trail option. The former looks much like existing XTR pedals. The new iteration, however, drops 50 grams, down to 310 grams per pair, yet nearly quadruples the amount of platform that makes contact with the shoe for noticeably improved stability.

The Trail version adds alloy extensions on the front and back of a slightly more robust main body for a nearly ten-fold increase in platform area over the old XTR pedals but just a 38-gram weight increase.

Wheels

Here, too, Shimano goes with two options. The Race wheels have scandium rims and 19mm inner and 23.3mm outer rim widths. The popular 15QR skewer setup will be an option up front, for those seeking stiffer and more precise steering. but rear hubs will be 9mm only. Claimed weight is 1,480 grams per pair.

The XTR Trail wheels take the same scandium construction but boost rim width to 21mm inner and 26.4 outer to accommodate wider tires and offer bigger contact patches. 15QR front hubs will be standard, while the rear hubs will offer the option of more robust 12mm rear axle. Claimed weights will be a relatively hefty 1,679 grams pair pair with a traditional rear hub and 1,700 with the 12mm rear.

Both the Race and Trail components should be in stores in October, both on complete bikes and as after-market parts. Shimano couldn't give us pricing yet, except to say it would be in line with current XTR prices.

—John Bradley