An Even Dozen: Shimano Deore

Shimano has completed the overhaul of their MTB groups. Their XTR, Deore XT, SLX and Deore groups have all been upgraded to 12-speeds, use Microspline freehubs and employ a 10-51 cassette for all 1x applications. While trickle-down economics may be a fiction, trickle-down technology at Shimano is very much a thing and the Deore group is a remarkable achievement in terms of taking the core technologies from XTR and putting them on low heat for the reduction sauce.

What matters
Deore is, if anything, a study in Shimano’s priorities. And what are those priorities? Well judging from what I’m riding, I’d say the three biggest, in no particular order are: 12 speeds, 1x, and Ice Tech brakes. These are just priorities, like making sure a meal has a protein source. The caveats and exceptions abound, like the fact that they do still offer 2x in every group except Deore, which underscores my point. They offer a 10-45 narrow-range cassette to pair with that front derailleur with the other groups. Pardon me while I giggle at how thoroughly our world has changed that we now refer to a 10-45 cassette as “narrow.”

While I continue to like front derailleurs and smaller steps between cogs, this Deore group has proven that in mountain biking the front derailleur is no longer necessary. My group features a 32-tooth chainring paired with the 10-51 cassette and I did a climb recently that normally reduces me to my lowest gear on another bike (34×46); using the 32×45 gave me a lower gear and left one more gear as a bailout. The day before, on a fast stretch of road on my way back to my car I never spun out the 32×10.

The group clearly has enough range thanks to the 10-51 cassette, but there remains the risk that the steps are too big between cogs. I can report that isn’t the case because the Deore group lacks one technology that was not deemed crucial to trickle down from upper-end groups: Multi-Release. This is the design feature in shifters that allows a rider to upshift up to two cogs at a time by depressing the upshift lever with the thumb (pulling it with the index finger results in single steps alone). Because the terrain is exceedingly changeable most places I ride, I found myself missing the Multi-Release feature. If I still want to upshift two cogs at a time after finishing a steep climb, it’s safe to conclude the jumps are not too big. That said, I might feel differently if I lived someplace where the grades are rarely ever steeper than 8 percent.

Stop now
I can’t recall many sets of disc brakes that didn’t stop well from the very first mile. On my opening ride on the Deore, the metallic brake pads seemed indifferent to velocity and momentum, that is, my velocity and my momentum. I’ll admit that I held some concern initially, given how I barrel into descents. Shimano does have a history of giving their higher-end groups more powerful brakes than their more budget-oriented groups.

Break-in didn’t take long, but the braking power changed significantly between the first mile and the fifth mile, by which time the braking power had increased so much I no longer had the feeling that I needed to brake early in order to control the bike. That break-in period is important to note; don’t let a test ride on this group fool you.

Are the brakes as powerful as a set of Deore XT? I think there might be a bit less braking power overall, but I think most riders will quickly get a feel for pulling a bit harder on the lever.

One other detail worth noting is that, unlike with some more value-oriented groups from SRAM, reach is adjustable on the Deore brake levers; changes require an Allen key, rather than a quick turn of a knob. Free stroke isn’t adjustable on this lever, but they did shorten the stroke for faster brake engagement.

The brakes I’ve been riding are two-piston; Shimano does offer a four-piston version of the brake as well.

What a drag
Unless someone has actually played with clutch tension on a rear derailleur they are unlikely to have a sense of just how much drag a 1x drivetrain can suffer. I find it irksome that in road riding people will discuss the merit and value of a lube that offers a 2-4 watt decrease in drag, while with mountain bikes next to no one ever mentions that a poorly tuned 1x drivetrain could rob a rider of a solid 20 watts and perhaps more.

Compared the the 11-speed 1x Deore XT group I’ve been riding for two years on a couple of different bikes, this Deore group is so much smoother I can’t help but wonder what Shimano learned in the intervening years.

Budget first
The group I’m riding is designated M6100. In addition to this, Shimano also offers an M5100 Deore, which features an 11-speed drivetrain as well as M4100, which uses a 10-speed drivetrain and cuts the cost by an additional 40 percent. I look at that M4100 group and I think bikes for kids.

Survival rate
My big question with this group, with all more price-conscious groups is just how well they survive. The bearings tend not to be as well shielded and the materials used in the brake and shifter levers wear out faster than in the pricier groups; ratchet teeth wear out sooner and pivots, like those for the brake levers, can develop play.

The degree to which this happens and the rate at which it happens depend on a few things in no particular order:

  • Rider weight
  • Rider ability
  • Ride frequency
  • Bike maintenance
  • Riding conditions

Of these, my experience is that rider weight, riding conditions and bike maintenance are the most crucial. The heavier the rider, the quicker things will wear out, period. Riding conditions and bike maintenance are closely related, but it’s possible to live in a place with relatively nice conditions but if the bike is cleaned with a power washer, that’s just as bad as riding in bad conditions and never cleaning the bike.

I’m going to continue to ride this group until I begin to see deterioration, at which point, I plan to follow up with a report on what problems I’m seeing.

Hidden purchase
I know a great many active people who have hidden gear purchases from spouses. The bigger the ticket (and the bigger the item) the harder it is to hide, which is to say my friend who bought a hang glider was outed inside of a month. The barn was big, but not that big.

Were I to advise a rider on how to hide their capital investment from a significant other (not something I’m actually volunteering for), the Deore group would be my advice. The complete group with the more expensive four-piston brakes goes for $597.93. I got TMJ when I read that price. I was expecting a figure that included a comma. That the cassette goes for $91.99 and the chain for $23.99 makes me wonder if I’m not in a time warp. I would advise shop owners to order these by the dozen.

Final thought: An alternative to splurging on XTR is just to order a new Deore group annually.


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