- In early 2016, SRAM launched the Eagle Groupset.
The 1 by 12 drivetrain that promised
to kill the front mech.
Now here is the GX Eagle.
It gives the same options
a much more wallet friendly price.
So, let's take a look.
(inspirational music)
So let's take a little look back in history first.
5 years ago, SRAM launched XX1,
the complete one by drive train.
This time last year, they launched Eagle
with that wide range cassette.
12 speed, as well, that's upping the game--
so it's a 10 all the way up to a 50--
giving you that 500% gear range.
Now this is GX Eagle, and it's aimed at that price point,
much more around the middle of the market,
the workhorse drivetrain where most
of us actually buy our bikes.
SRAM had to re-engineer everything to make
this 1 by 12 system possible last year--
so from the chain to the chainring,
the rear mech, and obviously that cassette.
They actually find that they had made
their most durable drivetrain ever.
So let's take a look at some of those changes
starting with the chainring.
So this is the X-Sync 2 chainring.
It's a narrow wide, so it gives you
that chain retention we've now come to love.
But also if you take a look at these teeth
they're really hooked, and that profile
really leads to this chainring being
quieter and more durable.
It just means that actually two of these teeth
are driving at any moment, so the load is spread
on that chainring so obviously that reduces the wear,
makes it quieter and therefore last longer.
So the chainring is available in a 30, a 32, and a 34
tooth variety and in two different offsets,
so 49, which is standard, and a 52 for boost bikes.
And they're produced by being stamped
and then CNC machined to get those tooth profiles,
which makes them much cheaper to build than the XX1
or XO1 Eagle equivalents but using the same technology.
Now, to the chain.
It's worth noting that SRAM engineered this drivetrain
as a complete drivetrain so everything works together.
For example, the chain really needs
to work really well with this cassette.
You got such a wide range, the chain lines move around
so much that whilst there are aftermarket things
like chainrings; they're just not gonna work quite as well
as this system does all together.
So the actual links to these chains called flow links,
and they're pressed 30 times, so pressed moved then pressed,
to get really chamfered edge, so like say,
those bigger chain lines,
you still get that really smooth shifting.
So SRAM have managed to keep the price down
on this chain by using solid pin
and this chrome plating compared
to the higher price chains which have that really fancy
ti-nitride coating and hollow pins.
Now let's take a look at the rear mech or derailleur.
So, the GX Eagle rear mech is actually the same build,
same length, as a higher price point ones,
the XO1 and the XX1.
It's just made more affordable
using more affordable material--
so a lower spec alloy, there's non-ceramic
bearings in here, and actually the time
that it takes to build this rear mech is less
so therefore, again, makes it cheaper.
You still have a roller bearing clutch in there,
a big 14tooth lower jockey wheel
to accommodate that wide range cassette
and also keep that pedaling smooth.
Another cool feature about Eagle
is it's all cross-compatible,
so if it's got Eagle on it, it'll work.
For example, you could upgrade
the rear mech to an XX1, or the chain,
or the cassette, and it will all work together.
Next, let's take a look at probably the most important part
of this whole drivetrain, the cassette.
So this really is the key piece of this drivetrain--
this 10-50,12 speed cassette.
We actually saw Nino Schurter win the Cape Epic
on a one by 12 Eagle system,
which a few years ago would have been unheard of.
So SRAM realised they needed that big 500% range
to make this cassette and the system
accessible to almost all riders.
But as well as that, they really spent a lot of time
thinking about the steps between the gears.
So the largest jump is 20% and that's from this 42
all the way up to that 50 to give you that lowest gear.
But on average there are less than
80% jump between gears.
The cassette is also the most complex piece to make.
The XX1 cassette, for example,
is actually milled out of one piece,
whereas the GX Eagle has individually
stamped sprockets that are then joined together
with stainless steel rivets on to an alloy backplate.
So the last two pieces of the puzzle--
we've got the GX Eagle cranks.
These are aluminium available in 165, 170, 175 mil lengths,
and also in the Descendant and Stylo ranges.
The shifter again is 1 by 12, obviously.
It's compatible with a MatchMaker system,
and also gives that adjustability, 10 mil left or right.
You got an aluminium trigger, so it's nice and durable,
in the case of crashes, and the cost
is kept down, on the shifter by using a bushing
in there rather than a bearing.
So let's take a look at just how affordable
the GX Eagle is.
Well let's take a look at a few parts to begin with.
The rear mech comes in £95.
Compare that to XO1, which is £185.
The cassette is £170.
Compare that to an XX1, which is £353.
For the overall drivetrain, an XO1 comes in at £987.
the GX Eagle, £425.
So, less than half the price,
but what is the payoff?
While a little bit of weight,
this is only 14% heavier.
(rock music)
So there is the first look at the SRAM GX Eagle drivetrain.
It's really cool to see all the thought that's
gone into really making it one full complete drivetrain.
And I've got to say that 50 tooth sprocket does make it
nice and easy to wind up even the steepest climbs.
If you want to see more videos from GMBN,
then click on the logo here to subscribe
if you haven't done already.
And click down there for how to fit a chain
and up there for our first look at a Rockshox Pike.
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