XT 8100 at a Glance
XT 8100 is as close to an all-new component ensemble as Shimano dares to release. Special ramps now ease the chain both down and up the 12-speed cassette. Assisted by a scientifically curated 12-speed chain, shifting speed is claimed to be over 30 percent faster.
The new Micro Spline freehub allows for a ten-tooth cog and the XT version provides a lightning fast (for Shimano) ten-degree engagement. Maximum gearing range from its 10 x 51-tooth spread is 510 percent and its shift levers can click off two gears in each direction with one push. In addition, the hollow aluminum cranks fit all popular widths and have direct-mount chainrings with steel teeth.
Hollowtech II Crankset
Steel Chainring:
The chainring teeth are tall and pointy, with profiles that stop short of the classic narrow-wide design, but still mirror the skip-tooth architecture. Shimano calls it “Dynamic Chain Engagement plus.” A lightweight aluminum spider is fixed to a plastic-encased steel sprocket withKey Features
Ride Report
Plastic film applied to the crank arm wards off scratches.
Pros
+
Proven performer+
More secure tooth profile+
Long-wearing chainringProven performerMore secure tooth profileLong-wearing chainring
Cons
-
Hard for me to get excited about the aesthetics.-
If you're a carbon fan - Shimano only makes aluminum cranks.Hard for me to get excited about the aesthetics.If you're a carbon fan - Shimano only makes aluminum cranks.
12-Speed Cassette
Key Features
Compare Shimano XT's 10-12-14-16-18-21-24-28-33-39-45-51 ratios to SRAM Eagle' s 10 x 50-tooth (500% range), which is 10-12-14-16-18-21-24-28-32-36-42-50. The limitations of 1/2-inch pitch chain dictate the first eight steps be the same. The remaining four reveal different thought processes. As explained to me by a secret development rider, Shimano's 18-percent jump from the 33 to a 39 was chosen to keep the first nine steps as close as possible, while segregating the three largest cogs (clustered in even, six-tooth jumps), specifically as climbing gears. SRAM's gearing, on the other hand, was intended for riders who prefer a more sequential gearing progression across the cassette. True or not, Eagle and XT cassettes have distinctly different personalities on trail.
Almost every tooth is modified for smooth shifts.
The numbers game:
Even number jumps do not calculate to even steps. The six-tooth step between Shimano's 45 and 51 cogs is actually aRide Report
Did I notice the ten percent lower gear? Not really, but it was nice not to run out of shifts at high speed and still have a stump-puller climbing gear. Shimano's switch to a ten-tooth top gear has been long in coming. In his First Look, Mike Kazimer preferred Shimano's six-tooth gear spacing at the larger end of the cassette, because the 45 to the 51 felt like a smaller step than SRAM. I found more instances where I was clunking back and forth, spanning that mid-cassette jump than I did wishing my largest cogs were closer. Not huge, but worth noting.
Seven largest cogs are fixed to an aluminum spider.
Pros
+
Best shifting cassette I've ridden+
Silent runningBest shifting cassette I've riddenSilent running
Cons
-
470 grams is a little clunky at this level470 grams is a little clunky at this level
Micro Spline Rear Hub
Key Features
Micro Spline freehub has a 10-degree engagement.
Pros
+
Smooth rolling and user rebuildable+
Very quiet freehub ratchet.Smooth rolling and user rebuildableVery quiet freehub ratchet.
Cons
-
No XT six-bolt brake rotor optionNo XT six-bolt brake rotor option
Rapidfire Plus Shift Lever
Key Features
Ride Report
Two-sided release lever.
Pros
+
Best feeling analog shifter Shimano has produced+
Consistent throw and intuitive feedback.Best feeling analog shifter Shimano has producedConsistent throw and intuitive feedback.
Cons
-
Why did we have to wait so long?Why did we have to wait so long?
Shadow Plus SGS Derailleur
Key Features:
Ride Report
Shimano's most recent improvement has been to tuck as many of the rear changer's vital parts out of harm's way as possible. What does protrude beyond the XT 12-speed derailleur's pivot knuckle is angled to ensure a glancing blow. Larger diameter 13-tooth jockey pulleys ride on sealed ball bearings inside a sturdy cage that is also designed to withstand a beating.This changer shares XTR's adjustable band type clutch and reduced cage tension in lower gears. The SGS model reviewed here handles the wide-range 10 x 51 cassette. A mid-cage option is available for customers who choose the close-ratio 10 x 45-tooth cassette.
Typically, you can set and forget a Shimano derailleur. Maybe you'll need to turn an adjustment barrel once to compensate for compressed housing, but that's it. So it was with my XT review. I needed one-half turn of the adjustment barrel three rides in and shifting has remained stable to date. My SRAM X01 Eagle bike is about the same age as the XT bike and it's already developed the usual free play at the upper pivot where the derailleur mounts to the hanger. I've been riding the heck out of both bikes this season and XT's pivot bushing is still like new.
Body designed to deflect impacts.
Pros
+
Sturdy and stable+
Tucked in design incurred minimal traumaSturdy and stableTucked in design incurred minimal trauma
Cons
-
Matte black finish top to bottom always looks dirtyMatte black finish top to bottom always looks dirty
Shimano XT vs. SRAM X01
SRAM's and Shimano's halo analog groups are Eagle XX1 and XTR. Their second-tier groups are Eagle X01 and XT 8100, so I'll throw them into the ring together. XT may be closer in price and weight to SRAM's GX group, but this fight is about how XT stacks up against X01.
Shifting performance of the two contenders is close, but Shimano has slightly better shift ergonomics. While both cassettes use ramps to guide the chain in each direction, Shimano's is the smoother and faster shifting of the pair.
Starting with the basic drivetrain (crankset, 32-tooth chainring, chain, rear-derailleur, and cassette), X01 comes out swinging, with an average weight that is
Eagle X01 sits just under XX1, the top dog in SRAM's cable-actuated range.
Pinkbike's Take:
Many joke that XT is the poor man's XTR, but in this case, that statement could be amended to "smart man's XTR." XT 8100 components are not inexpensive, but their performance is so close to XTR that emotion may be the only motivation to buy Shimano's premier group. Part for part, you'll spend around $1,000 USD more to ride XTR, (or SRAM XX1) and your bike will weigh about a half-pound less.
I emphasize cost versus performance in this review, because I believe that the design and function of the modern trail bike has stabilized. This presents an opportunity for bike and component makers to strip off the excess of their halo products, and to distill the price of pro-level performance to a more attainable figure. The concept is picking up momentum. Shimano XT 8100 is exactly what the sport needs more of.
Deore XT is destined to live under the shadow of Shimano’s over-the-top XTR trust-fund baby. Don’t shed any tears, though, because XT may be the more stable and trustworthy member of the family. XTR’s creators occasionally overreach in their quest to out-perform their last opus. When they return to craft the next XT components, the engineers address those issues. As a result, XT can perform as well (sometimes better) as its haloed brother.PB showed you Shimano’s 12-speed XT 8100 back in May, 2019 when it was first released. We were duly impressed with its performance and promised a long-term review to see if we could sus out any chinks in its armor. This is it.The brakes are new as well, copying XTR’s stiffer mid-clamp lever perches, while the brake rotors share XTR’s cool running stainless steel/aluminum sandwich technology and feather-light aluminum spiders. Two- and four-piston calipers are sold, and feature cooling fins on their newly-formulated brake pads. We reviewed those earlier this year. The focus of this review is on the XT 12-speed drivetrain.tamper-proof screws. Reportedly, the small weight penalty of those steel teeth saves half the cost of an XTR chainring – and they last longer too.I am not sure why the plastic on the spider is necessary. My guess is that it’s a cosmetic treatment to hide the hardware at the four spider attachment points. Okay, but it looks a little cheap. Ending on a higher note, Shimano applies clear protective “helicopter tape” to the outer surfaces of the crankarms, which should keep your shoes from scuffing off the anodized coating. So far, they're looking fine.Bottom line? One-by drivetrains have eliminated the need for bike makers to serialize chainrings and cranksets, so this is one of the first components they'll switch to save a few bucks. Shimano's Hollowtech II crankset design, however, has proven itself in all forms of competition. Add the more secure tooth profile and expected longevity of its hybrid steel chainring and it could prove to be a performance value in the long run.The first two cogs are aluminum, riveted to a lightweight spider, along with five steel cogs. In Shimano tradition, the remaining steel cogs slide on individually. The XT vs XTR penalty is nearly 100 grams, with XT's 10x51 option weighing in at 470 vs 367 grams. Weigh the MSRPs, though, ($160 vs $380 USD) and that 100 grams should be no imposition.Even number jumps do not calculate to even steps. The six-tooth step between Shimano's 45 and 51 cogs is actually a smaller percentage than the six-tooth step from the 33 to the 39 cog. Increasing the number of teeth between shifts to larger cogs helps to keep the delta between gears at the same percentage. Counterintuitive, perhaps, but that's why wide-range cassettes have parabolic curves.Shimano rises to the top on shifting performance. SRAM has also included ramps to ease the chain down to the smaller cogs, but XT is next level. Full power climbing shifts occasionally will emit a grunt from the cassette, but for the most part, the cassette runs quietly. Pop off a couple of up-shifts while powering over the top of a rolling climb and you'll feel nothing but a smooth transition to a faster gear. XTR introduced Hyperglide + shifting, but XT seems to run even more quietly, and that improved as the cogs wore in.Shimano does an incredible volume of real-world testing, so I assume there's a sizeable number of riders out there who will disagree with me. I would rather ride a cassette with more sequential steps. That said, I wasn't bothered enough to remove it for another option. Superlative shifting handily trumps a minor mid-cassette dead spot.Enough wheel makers have been granted use of Micro Spline to assuage customer fears of being trapped into purchasing Shimano hubs and wheels for life. The up side is that the new spline design will take massive amounts of torque when constructed from aluminum - so, lighter and stronger, and no more galled freehub splines.Shifting firmness feels similar to SRAM's Eagle XX1 or X01 triggers, but with better ergonomics at the touch points. Shimano fans will be happy to know that the release lever can still be operated by thumb or forefinger action.One indicator of a stable rear derailleur is how well it can handle adversity, like brush winding into the pulleys, or leaf litter clogging the cassette. Few disturbances can ruin a mountain biker's flow faster than a chain randomly skipping over a tiny stick lodged in between cassette cogs or a jockey pulley. Autumn in Southern California guarantees those moments, so it came as a pleasant surprise that the XT cassette and derailleur shrugged off the barrage of dry brush and prairie grass leaning into the singletracks. A couple of chain skips, then silence, and my precious flow would resume. I could count on it. That's not how it normally goes.almost 250 grams lighter. Shimano takes the first hit in the crankset (620g vs 483g) boom, and then another punch in the 12-speed cassette (470g vs 357g). Ouch! But, the weight advantage of SRAM's carbon cranks and one-piece CNC-machined Powerdome cassette can't hold up to Shimano's MSRP - a $650 USD blow to the head from XT. Ba-boom! X01 wobbles back towards XT, swinging wildly for 650 bucks worth of tangible performance, but can't quite connect. The decision goes to XT.
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