Shimano released a full suite of wireless mountain bike drivetrain components back in June.
Much has been written about the release of XTR, XT and Deore Di2, but how do they compare in the real world?
We‘ve had the key components of each family in the BikeRadar office, so we decided to see how much they weigh and what their key differences are.
Shimano MTB Di2 derailleur weights and key features
- XTR: 390g, £549.99 / $665
- XT: 450g, £429.99 / $670
- Deore: 497g, £374.99 / $435
- Battery and charger: £39.99 / £29.99, $55 / $45
Shimano offers the XTR M9200 and XT M8200-level derailleurs in four flavours, and the Deore M6200 derailleur in three.
All three families have two ebike-specific derailleurs, one for 12-speed Hyperglide+ drivetrains and one for 11-speed Linkdrive.
These derailleurs plug into your eMTB battery, leaving the inner parallelogram free of a battery.
The non-eMTB derailleurs have a battery held in the parallelogram. Both XTR and XT families offer two cage lengths – a longer SGS cage version for a 10-51t cassette, and an SG option, with its short cage built for the new 9-45t cassette.
The Deore Di2 derailleur has the longer SGS cage, with no SG option offered.
While materials and finishes differ, the most noticeable difference is the use of a carbon cage on XTR, alloy on XT and steel on Deore.
While the addition of the 9-45t cassette is an interesting option from Shimano, offering better ground clearance on enduro and mullet rigs, or lighter weight on XC bikes, I suspect most bike brands and riders will opt for the traditional 10-51t cassette option.
As such, the cheaper price of the Deore derailleur makes it the one I would likely pick.
The durability of Shimano's mechanical groupsets at this level has rarely caused me any issues; a steel cage is neither here nor there in performance terms, and the extra few grams aren’t going to bother me when my bike is covered in mud.
This would be my pick of the bunch if I were building a drivetrain with a 10-51t cassette.
Shimano MTB Di2 shifter weights and key features
- XTR: 98g, £184.99 / $220
- XT: 97g, £159.99 / $190
- Deore: 85g, £124.99 / $140
One shifter is offered at each level of drivetrain hierarchy.
The XTR shifter has the most features, although they’re in short supply.
Both lever paddles are mounted on a ball joint, enabling their exact orientation to be adjusted for personal preference.
The two paddles can be swapped around, too, and being slightly different sizes and shapes means there are even more fit options.
The XTR shifter has the option to mechanically limit the paddles to a single click. Turn a dial on the shifter body and you won’t be able to push through to the second shift.
This feature is aimed at riders of eMTBs, who may not want to smash through the gears while the drivetrain is under additional power.
The XT shifter shares the adjustable paddles, but lacks the ability to prevent a second click from occurring. The Deore shifter doesn’t have adjustable paddles.
I’m quite picky about my shifter-paddle placement, so the adjustability offered by XT and XTR is a bonus in my eyes. I’m not sure I’d need to stomach the extra cost of the XTR unit, and quite like a double-click on the shifter – it’s one of the reasons I prefer Shimano’s mechanical shifters over SRAM’s.
As such, the XT shifter would be my pick of the bunch.
Shimano MTB Di2 crankset weights and key features
- XTR (165mm / 30t): 584g, £249.99, £129.99 / $310, $150
- XT (170mm, 32t): 607g, £149.99, £64.99 / $190, $73
Shimano hasn’t updated Deore’s crankset; instead, the existing M6100-level components are carried over.
However, both XTR and XT have new cranksets on offer.
XTR is split into two – an XC version and another for enduro bikes.
The XTR XC cranks (M9200) have a lightweight spindle to save weight, and a narrower Q-factor (170mm). They’re offered in 165 to 175mm lengths and chainrings range from 30t to 38t.
The Enduro cranks have a stiffer spindle and a 176mm Q-factor, in lengths from 160-175mm. Chainrings range from 28-36t.
At the XT level, there’s only one flavour of crankset. It comes in lengths from 160-175mm, with a 176mm Q-factor and chainrings from 28 to 36 teeth.
The blanked-off portion of each of the chainrings is clocked to be stiffer at points where they’re more likely to hit rocks and logs, when the cranks are level.
I’m going to go out on a limb here and say that I’d pick the XTR cranks.
Yes, they’re more expensive, and I’m not too bothered about weight differences.
However, aesthetically, I think they’re the best-looking cranks on the market. And so the heart wins out over the head.
For what it’s worth, I’d go for the Enduro cranks in a 165mm length with a 30t chainring.
Shimano MTB Di2 cassette weights and key features
- XTR (9-45t): 329g, £399.99 / $500
- XT (10-51t): 464g, £149.99 / $195
Once again, Deore users will look back to the M6100-level components for their 10-51t cassettes.
XT and XTR customers have the option of two cassettes. There are the 10-51t versions and a new 9-45t cassette in both families.
The key difference comes from the use of titanium sprockets in the XTR cassette, along with alloy and steel. The XT cassette mixes alloy and steel sprockets.
The 9-45t cassette is there for riders who want to increase ground clearance (by using a smaller chainring and the SHS short-cage derailleur), while maintaining a 500% gear range.
The 9-45t cassette requires its own tool to fit it to a Microspline freehub body, because there’s no space for a regular cassette lockring.
While most people will opt for the 10-51t cassette, I think the smaller 9-45t option is compelling for enduro riders who’re worried about banging their derailleur on rocks, especially on mullet-wheeled bikes.
While 9t sprockets aren’t as smooth or efficient as 10t sprockets (their efficiency increases with size because there’s less rotation in the chain’s rollers), my experience is that the highest gear is used far less than others. If it is your most-used sprocket, you might want to consider increasing the size of your chainring.
