Shimano 12 Speed SLX, XT, XTR Drivetrain, Cassettes, Freehub, Installation


Hey everyone, welcome to my channel! Apparently it took Shimano 4 years
to design their 12 speed drivetrains, and today we don’t just have the XTR
introduced in 2018, we have the XT, and the mid tier SLX, so why don’t we take a closer look at the cassette, which is at the heart of the new redesign. The three group sets provide two cassette options: one, that’s called a Rhythm Step, the 10-45 tooth, and the second one, 10-51t, which is the wide range. For our discussion today I’m gonna use the XTR 10-51t, and the XT 10-51t. SLX is very very similar to this, and I’m gonna mention those differences. In order to provide us with the 10 tooth cog, Shimano had to redesign the
freehub body we’ve been using for a while, and they introduced what’s called the
MICRO SPLINE. With the old design we had a lock ring,
tightening up this 11 tooth cog which was the smallest you could fit. And you can see how that sits right at the end of the freehub body itself. With the MICRO SPLINE design,
you still have a lock ring. The XTR cassette has 4 loose cogs, then you have Titanium, the next 5, and
aluminum, the last 3. All of these being installed on this aluminum spider, with the Hollow Beam construction. Similar to that XT and SLX use 5 loose cogs. And that is followed by another 5 steel cogs , and the two aluminum that are on
the aluminum spider, using the same Hollow Beam construction over here. The only difference between this and the SLX is the fact that SLX has an steel cog here,
on the 45 tooth cog. XTR uses what’s called a low spacer. It slides onto the freehub body first, before the cassette, and it prevents creaking. SLX and XT cassettes have that already applied, in the form of a sticker,
you see that shiny surface over here. Shimano had to use 3 aluminum cogs,
then Titanium cogs on the XTR to come close to the SRAM Eagle weights. This is 369 grams, which is still about
10 grams heavier than the XX1. XT uses 2 aluminum cogs, and no Titanium. The weight comes up to 470 grams, which is about 20 grams more than the Eagle GX that only uses one aluminium cog. Finally, SLX that only uses one aluminium cog, will come up to 534 grams. One of issues with the original Shimano design is that when made out of aluminum, these freehub bodies would get damaged
by the loose cogs in the cassettes. It can get so bad that you would have to
file them down in order to reuse them. When SRAM introduced the XD driver in
2013, they solved that issue and also that allow them to install a 10 tooth cog. We already know that MICRO SPLINE allows Shimano to install a 10 tooth cog, but what about the gouging issue? This was used for about 2 months with that XTR cassette, about 500 miles, and you can see how the loose cogs started to bite
into the micro splines. So I think Shimano probably solved the issue to an acceptable level, but they didn’t completely clear the gouging issue
of the freehub body. Also, the installation of these cassettes is a bit more complicated than before. First, you have to worry about this low spacer but only
in the case of the XTR, Slide in the carrier, followed by the 18 tooth cog in case of the XT and SLX. XTR, that’s only using 4 loose cogs, it’s gonna use the 16 tooth, followed by this really thin spacer. XT and SLX are going to use a thick spacer over here, the 16t cog, and then the same thin spacer that XTR uses, and finally, the last 3 steel cogs
are installed without any more spacers, and they seem to be almost
identical between the three cassettes. To install these right, Shimano provides
these alignment marks, you see the little dots on the 10t, 12t, and 14t cogs. The 14 tooth is going to slide on to the spline, that is followed by the 12 tooth cog, properly lined up with the little dot. You’re gonna see that the 12 tooth cog is acting like a cap for the MICRO SPLINE freefub. That means that the 10 tooth cog has nowhere to go but to attach to the 12 tooth cog. Put them one on top of the other, and now you can use the lock ring
and tighten this up to 40 Nm. But that’s just for the XTR, XT and SLX only have the dot on the
10t, you see it here, and the 12 tooth cog. By not having it on the 14t, I found myself
struggling to find the right position of this 12 tooth cog which is the actual cap. Pay attention to this one tooth, that is very similar to the one on the 14 tooth,
like a shift ramp. If you line them up, that’s the right position and then use the dot for your 10t cog. If you follow my channel, you know that I’ve been using that XTR shifter, with an XTR rear derailleur, this is the long cage, together with an SRAM Eagle 10-50t GX cassette. Why don’t we install the Shimano
cassette and chain, and see how it goes. The 12 speed chain it’s a critical
component of the HYPERGLIDE+ system. It has specially designed plates, for better
chain retention and smoother shifting. It is a directional chain, as you see over here, you have nothing written on the plate
on the non-drive side, and you have Shimano written here
on the plates on the drive side. And for installation, you’re gonna have this quick link, that is not reusable by the way, Then, as per Shimano, measure big-to-big, plus one, two, three, four, is going to be five in the case of this hardtail. they recommend four or five plus the quick link. Then cut your chain, just be careful because some of the chain tools that you might have, like this expensive Park Tool, won’t be compatible with 12 speed chains from Shimano. Then route the chain through the derailleur, and remember that the quick
link is directional, the arrow on this outer plate should be pointing towards the derailleur. With the exception of the chainring I have a full Shimano 12 speed drivetrain. The beauty of it is that
they’re all interchangeable, XTR, XT, SLX. One last adjustment to pay attention to is the B-gap, or the distance between
the top jockey wheel and the cassette. Instead of a tool, they have a
line right there on the derailleur cage, to make this super easy. And if you had
issues with your 11 speed Shimano drive trains, the 12 speed doesn’t have any issue
backpedaling on the biggest cog. The original Hyperglide
took care of the smoother shifting into the larger cogs. HYPERGLIDE+ of the 12 speed it’s supposed to help when shifting into harder gears or smaller cogs. Let’s take a look! Not too bad, actually pretty smooth. And a bit faster now. And here’s the same chain, XT chain, with
an XT brand new cassette. Might be a bit smoother I think… This works perfectly fine… So what do you guys think? I believe the improvements are
incremental from what we’ve known I also remember hearing the product
manager from Shimano talking about HYPERGLIDE+ making a difference under power, so I obviously have to do a bit more testing on this, to prove that the
new technology really makes a difference Add to that an interesting derailleur
design, that looks bent and twisted, I have a video about that on my channel, and I think Shimano gave us three groupsets that are solid, and we’re gonna see a lot of this in the 2020 bikes coming out soon. What about you guys
sticking with me all this time? Do you plan to buy a MICRO SPLINE freehub and put it on your existing bike? Are you going to buy any of the Shimano groupsets? Do you plan to buy a new bike with Shimano already installed on it? I’d love to hear from you in the comments below. If you found this useful, don’t forget to Like, Subscribe, keep an eye on social media and until next time, hope to see you folks on the trails. Cheers guys, Cheers!