Upgrading to Shimano XT 12-speed

Lester Perry | Tue 30th Jun 2020 01:21

With Shimano recently launching a number of new 12-speed groupsets, perhaps now is the time to start thinking about replacing parts... Upgrading bike components is often the most cost effective way to improve a bikes performance, rather than buying a whole new bike! Here's Lesters experience after upgrading his Trek Fuel EX to the new Shimano Deore XT 12-Speed groupset and wheelset.

Buying a new bike every season to keep up with the latest technology is out of most peoples reach, and with manufacturers generally updating frames each 3 years or so is there really much to gain by upgrading to the latest year model? Upgrading your existing bike will be easier on the wallet, and you could revamp your ride for a fraction of the price of a new one, leaving some dollars in your wallet for your next riding trip!

There are a myriad of reasons why you may want to upgrade your bike, outside of just giving it a refresh. Perhaps you’re still running older model 10 speed, perhaps you’re running multiple front chainrings and it’s time to just have one, perhaps your brakes have been damaged in a crash, or maybe your drive-train is so worn it’s beyond repair and makes more sense to buy a completely new one? Maybe you love your existing bike but want the latest groupset in order to lighten things up a bit, or simply one-up your riding buddies! Whatever the reason, upgrades are a great way to bring new life into your old rig.

Recently I undertook an upgrade on a current, but well used Trek Fuel EX. I decided to deviate from the standard spec’d, and somewhat tired SRAM GX, which has been in the market a few years, and update to the newly released Shimano Deore XT 8100 series 12 speed, including brakes and wheels.

Shimano Deore XT 4-Piston Brakes

Powerful brakes are great, but power is only as good as the modulation your brakes offer. Good modulation gives you accurate control of how the power is applied at the caliper. Most older brakes suffer from a lack of modulation and can have an “on” or “off” feel, too much “on” and you’ll break traction and won’t slow down. Too much “off” and you simply won’t slow down. Brakes with ample modulation let you temper the power just right, and slow down while maintaining control of your traction and speed. Brakes are often overlooked as an upgrade because many people consider a good brake to be one which simply locks up your wheel when applied, these days even the most basic of brakes can achieve this. An upgrade to a modern brake will give you both power and modulation, making a huge difference to your riding.

Having spent a lot of time on the previous generation of Shimano XT 2-piston brakes, I was a fan of them for their power and lack of maintenance required. While the power on offer was good, the modulation could have done with improvement and they had a very on/off feel. At times the “bite point” (the point in the lever stroke where you feel the brake pads hit the rotor) also tended to wander. Meaning, in some situations it could be hard to judge your braking points or even control traction, and the inconsistency played on your mind...

For the latest M8120 brakes, Shimano made a myriad of changes over the previous edition, so I was hoping for big things from the new 4 pot units, and needless to say they didn't disappoint. Consistency, modulation, and increased power - the new XT brakes tick all the boxes! Aside from the addition of the extra 2 pistons per caliper, the most visible change is a small “perch” on the brake lever that rests against the handlebar in order to give the lever more stiffness and aid the overall power and solid feel of the brake.

A fresh set of brakes is a cost effective upgrade that can make a huge difference to your overall riding experience, no need to put up with subpar braking any longer!

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Shimano Deore XT 12-Speed Drivetrain

With a whooping 51 tooth low gear available on the M8100 12 speed cassette it would be easy to consider the additional gear range this offers as the main feature or upgrade over the 46 tooth on previous XT series. While the extra range is welcome as you grind your way up a long climb, the most welcome advantage I've found is from the new Hyperglide + tooth profile. This essentially takes the technology that previously has helped you easily shift to lower (i.e. easier) gear smoothly, and applies it to upshifts (i.e. harder). This allows you to keep the power down as you bang through the gears as you pick up speed quicker, and provides more solid shifts as a result. While it doesn’t sound like anything groundbreaking, compared to previous Shimano drive trains and other brands offerings, Hyperglide + sets a new standard for shifting under power.

While Hyperglide + is a jewel in XT’s crown, it’s only as good as the shifter, chain and of course, the derailleur that enables it to do its job. I think the old adage of “If you don’t notice it’s there, it’s doing its job well” applies here. The shifter itself does its job faultlessly, while downshifting the “thumb” lever feels positive and sturdy, and during upshifts the “release” (operated by forefinger or thumb) is snappy. And, like the previous series, one of my favourite features of high end Shimano shifters is the ability to shift through multiple gears higher in one motion. The other welcome change is the lever feels lighter than the 11 speed version, much less force is now needed to change down to an easier gear.

Integrated I-Spec shifter/lever mount makes for a clean appearance

Shimano Deore XT Wheelset

Buckled wheels, worn out hubs, overweight or old technology - there are numerous reasons you may want to upgrade your wheels. Consider the type of riding you’re doing and find an applicable wheel. If you're strictly riding mellow trails and not searching out jumps then having a downhill rated wheelset will only slow you down as it adds unnecessary weight to your bike. On the other hand, if you’re seeking out jumps and hammering downhill runs, a light weight cross-country wheelset won’t be up to the task. Wheels come in all shapes, sizes, and materials. Each of these factors can entirely change the way your bike feels so it’s important to consider your options carefully.

The latest XT Trail wheelset changes things up slightly from the previous, stretching its alloy rim bed out to 30mm internally, putting them smack in the middle of modern rim widths - just right.

Setting up the XT wheelset was an absolute cinch. The wheels come taped for tubeless, and tubeless valve pre-installed so all I had to do was add tyres and sealant. The tyres beaded up with minimal effort, and although I used a “Charger” style pump, a regular track pump would do the trick easily I'm sure.

Like the front hub, the rear rolls on tried and true cup-and-cone style bearings, doing it’s thing faultlessly. This rear hub differs significantly from the old one however. Hub flanges are now wider apart, meaning a stiffer, stronger wheel. There's other magic happening here too - Shimano launched its new ‘Micro-Spline’ freehub alongside their 12 speed drivetrains. With 12 gears, and a 10 tooth small cog, the “old” Shimano HG freehub was no longer fit for purpose (too short, and too ‘fat’) so it was time to rewrite the rules. The new Micro-spline freehub body is smaller overall to fit the 12 speed cassette. The drive rings inside the freehub are made out of aluminum, not steel as on most hubs, contributing to the hub's overall light weight. Initially it was difficult to find Micro-spline compatible hubs and the market kicked up a bit of noise about having to adopt yet another ‘standard’. Almost a year since launch however, Micro-spline is now easy to find as either an upgrade to an older hub body, complete new hub, or aboard an OEM wheel on a new bike. This technology now trickles down through most Shimano MTB offerings (XTR, XT, SLX & DEORE) meaning Micro-spline, and its accompanying 12 speeds are here to stay!

Shimano Deore XT Cranks

Upgrading your crankset probably won’t give you a noticeable advantage over your previous one, however changing your crankset may be worthwhile, or even necessary depending on what other component’s you’re swapping out or upgrading. Stiff, lightweight and good looking, what more could you ask of a crankset? The XT 8100 crank ticks all the boxes, and using Shimano's tried and true fixing system, fitting them couldn't be simpler.

An updated crank shape and a protective tape on the crank arms protects against scuffing.

One issue many people (myself included) had with the previous XT cranks was how easily the coloured coating rubbed off them. The shape of the arms lent themselves to being rubbed by your shoes while pedalling. This time around we see a revised crank shape and the addition of a protective tape on the crank arms - problem solved!

Without a chainring though, cranks are useless, the 8100 series chainring shakes things up from previous years, this time using a direct mount to the crank rather than a more traditional (and heavier) spider style set up where the chainring bolts to the crank spider. The chainring itself features a steel outer ring that's attached to a lightweight inner alloy “spider” portion, keeping things lightweight but hard wearing. Having been impressed with how sturdy and hard wearing the previous XT chainring was, this one looks to continue the trend.

While Shimano initially rolled out 12 speed in their flagship XTR and XT ranges, this technology now features right across their MTB range, meaning there’s a 12 speed groupset for every budget.

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