While Shimano just released some revised budget mountain bike groups that stick with status quo regarding 10 & 9 speed gearing options, they also are dripping out some more updates that apply to a wider range of mountain bike builds. At the highest level that starts out with a long needed update bringing Boost spacing to their XT wheels for both 27.5″ & 29er formats. The also have quietly debuted a new wide range SLX cassette that should make 11 speed Shimano fans happy, whether for 1x or 2x drivetrains. Then there is a newly designed version of the e-thru axles that significantly reduced their profile for improved clearances, and lastly a couple of non-series cranks that bring their non-standard 4-bolt 94mm BCD to a more affordable pricepoint…
XT wheels
The wheel update is pretty straight forward. Shimano has four basic XT wheelsets – XC M8000 with 23.9 external/20mm internal & Trail M8020 with 27.9mm external/24mm internal rims, available in both 27.5″ & 29″ diameters. All four now get Boost hub spacing in their thru-axle variants. The extra 10mm up front and 6mm out back means wider hub flange spacing and thus improved stiffness at both ends.
SLX cassette
In terms of 11 speed drivetrains, bringing the wide range 11-46 cassette that had been unique to M8000 XT down to the SLX level should mean both a lower replacement cost for XT drivetrians, as well as more affordable entry into single ring setups. The SLX rear derailleur had already been rated for a max 46T cog when used as a 1x, but Shimano says its max for a 2x is a 42T cog due to its cage length being able to deal with a max range of 41 teeth total. Most modern doubles have 10 tooth spread, falling out of range by four teeth for a 2x setup, but at the SLX level the new CS-M7000 cassette might just be affordable enough to experiment whether it will work on your bike.
Shimano hasn’t given us pricing to see how big of a drop will be though. We also don’t have a claimed weight, but from its look it may be identical to the XT. It shares the same cog layout with that big last step (11-13-15-17-19-21-24-28-32-37-46), and the spec sheet labels it the same steel cogs with the biggest being aluminum. The only difference we see is a steel SLX lock ring vs. the alloy one on XT.
E-thru axle
The updates to what Shimano calls their e-thru axles amounts mostly to a lower profile lever layout. The have dropped the large tool free position adjustment dial (blue above) in favor of an adjusting nut on the axle that you set with a standard 10mm hex wrench. In the process they dropped a whole 10mm off the overall width of the lever mechanism. Since you really only need to set the position of the lever the first time you install a wheel in the bike, wrench adjustment seems a good trade-off.
The update also had Shimano redesign the final position of the closed internal cam lever. Now it closes flush with the face of the dropout, instead of before when it came 6mm further in. That means more room around frame members and more importantly the rear brake. A side benefit of it all is reduced weight, available both for regular and Boost spacing.
Non-series bits
While the Deore redesign earlier this week stuck with 10 speed, Shimano sees a lot of OEMs looking to might their more affordable cranks with higher end drivetrains. At the same time a lot of customers buying aftermarket kit might want to balance price and performance. So Shimano has a couple more new cranksets in their non-series line-up that hit at the Deore level. Both use Shimano’s asymmetric 96/64 4-arm BCD and go with 36/26 gearing. The MT600 (top) is a 2×11 setup available for standard or Boost spacing, and the MT500 (lower) is destined for a 2×10 and sticks with a standard 48.8mm chainline.
Also in non-series news is a Deore-level double-sided XC pedal (PD-ED500) and a set of hydraulic disc brakes (BR-MT500) that are essentially rebranded Deore M6000 stoppers, all of which should be available by May 2017.