2019-05-01_Mountain_Bike_Rider

mbr

ratings

explained

The scores

on the doors

M AY 2 019 mbr 101

1-4 5-6

Something’s wrong. It’s rare, but sometimes

a product will have a design fl aw or some

other weakness that means we can’t

recommend it. Steer clear.

OK — one or two

faults but it has

potential.

7

Good —

worth

considering.

8

Very

good

— for the

money,

we’d buy it.

10

Simply

the best

— we couldn’t

fault it.

9

Excellent

— a slight

mod or two

and it might

be perfect.

W

hile SRAM has recently soared to new

heights with the pricing of its Eagle

AXS wireless drivetrain, last year

it swooped down to earth with the

value-orientated NX Eagle, and we’ve

been riding it ever since.

For £365 you get a shifter, cassette, chain,

DUB-compatible cranks, r-mech and a B-tension

tool. On top of that, to make it rideable, you have

to buy a cable and housing and a DUB bottom

bracket, but considering you can buy the drivetrain

online for considerably less than full price, it’s still

impressively aff ordable.

To put it into context, NX Eagle is £130 cheaper

than GX Eagle, with the biggest saving to be found

with the cassette. To do this, SRAM has reduced

the Eagle’s wingspan: instead of 10-50t, NX Eagle

is 11-50t. It’s still 12-speed, making it (almost) fully

compatible with all the other Eagle drivetrains, but

you sacrifi ce around 10 per cent at the top end of

the gearing. The reason for this is simple: NX Eagle

fi ts the older splined freehub

design instead of the unique XD

driver used by GX and upwards.

On the one hand this gives you a

wider choice of wheels and hubs,

and will make upgrading to Eagle

simpler and cheaper for some

people. On the other, if you choose

to upgrade from NX to one of the

more expensive Eagle drivetrains

further down the line, you will have to buy a new

freehub body, which will add to the cost.

Also in the name of aff ordability, the cassette uses

stamped steel sprockets, four of which are pinned

to an alloy carrier and eight of which are separate.

As such the PG-1230 cassette is a heavy lump of

metal. It weighs well over 600g – 166g more than

GX Eagle and 254g more than XO1 – all of which is

unsprung weight on a suspension bike. Along with a

rear derailleur that’s 60g heavier than GX, it means

you won’t be able to enjoy ultimate suspension

performance with NX Eagle, as the bike will feel less

sensitive than it would with a lighter set-up.

Elsewhere the shifter and derailleur use

more steel and plastic than aluminium, but the

construction and fi nishing are fi rst rate and only a

close inspection reveals any cost-cutting.

In addition to our sample drivetrain, we’ve racked

up the miles on many NX Eagle test bikes over the

last seven months, including plenty of e-bikes as it’s

the only SRAM Eagle drivetrain recommended for

that application. On the whole our experience has

been very positive, but we have had a few issues. So

fi rst the lows.

As we’ve already pointed out, that cassette is

hefty, which has some knock-on eff ects. Because

you can put so much torque through the 50t

sprocket, if you run it on a softer alloy freehub body

you may fi nd the cassette winds into the splines

and becomes diffi cult to remove.

The rear derailleur hangs really low, making

it particularly vulnerable to damage from rocks,

stumps and fl ying debris. Despite having the

redesigned lower pulley with raised shoulder, we’ve

broken and bent a few Eagle rear mechs now,

including our original NX sample. It’s hard to say

exactly what’s at fault here, but we believe the long

cage and wide knuckle do increase the chances of

damage. As a counterpoint, there are more Eagle

equipped bikes than ever before out there on the

trails, so incidences of failures will always increase

in line with overall use.

Now for the positives. Shifting is excellent. Yes,

it has a slightly heavier action than the top-end

drivetrains, but go for an easier gear under load

as the gradient steepens and NX

will shift accurately and quietly

without protest. Of course you

have to make sure everything is

set-up precisely — particularly the

B-tension adjustment — but it’s

no more sensitive than any other

Eagle drivetrain in that respect.

Equally, the slightly narrower gear

range didn’t bother us. We rarely

use the 10-tooth sprocket, so it was no great loss,

and if you do love hammering a big gear, you can

always run a bigger chainring.

Chain retention is also excellent and we haven’t

dropped a single chain that we can remember, even

without a guide. Also, wear has been minimal with

only a few sprockets showing glints of bare metal,

while the chain has barely stretched.

The crank (we were sent the wider, burlier

Descendant model that costs the same as NX

Eagle) is excellent — it’s stiff , light thanks to the

alloy axle, and also comes in 165mm lengths, which

is good news if you’re running a super low BB.

It’s easy to focus on the extra weight of NX Eagle

and lose sight of the big picture. Yes, there’s a

penalty to be paid for running that heavy cassette

on a suspension bike, but stand back and take in

the additional gear range, precise

shifting and aff ordable price

and it’s clear that NX Eagle is a

ground-breaking drivetrain that

will let you climb further and

longer than ever before.

Danny Milner

SRAM NX EAGLE DRIVETRAIN

£365

SPECIFICATION Weight: 1,957g • Includes: shifter, cassette, chain, cranks, r-mech, B-tension tool • Contact: sram.com

WEIGHTS AND PRICES

Cassette 614g £99

Rear mech 341g £106

Shifter (excluding

clamp)

112g £34

SRAM Descendant

crank 170mm, 32t

640g £104