With its ‘upside down’ layout, full-carbon upper legs and exposed stanchions, the RS1 has raised a lot of questions about its longevity. We’ve had this RS1 in action for almost 10 months now, so let's take a look back at how it has fared.
First up a quick
recap… It retails for $2,300 and you also need to buy the matching proprietary
hub, so it’s crazyexpensive. Still, I’ve seen a number of riders using them and
they come as standard spec on some $6,000 hardtails.
The design places the
largest part of the structure up near the crown; right where the leverage is
greatest. Instead of using a brace, the massive 27mm diameter axle of the Predictive
Steering hub serves to tie the lower legs together.
Initially we mounted
the fork to a carbon hardtail, replacing a RockShox Reba. The swap straight-out
transformed the ride. It felt more controlled and didn’t twang back and forth
when braking into rough corners. We were pretty stoked with the performance and
while it’s around 130g heavier than a SID World Cup XC fork, the added control
was appreciated whenever the trail turned rough.
The RS1 can be set to
offer 80, 100 or 120mm of travel, so next we tested it on a 120mm trail bike.
The fore-aft stiffness remained a highlight; it’s clearly more stable when
braking and it doesn’t feel like it wants to fold back underneath you.
When compared to a
good 120mm travel trail fork, the RS1 seems to suffer a bit more stiction. One
of the supposed benefits with an upside down design is the permanently lubricated
seals. However, if you push down on the bars and gradually increase load, the
fork resists movement until you reach a certain point, then it suddenly falls
into its travel. I tried a few other RS1s and they shared the same trait. An
oil bath and air piston service did improve things but still wasn’t the most supple
in this regard.
While this stiction
would generally be seen as a negative, it actually seemed to serve a purpose on
the RS1. It is pitched squarely at the XC racer and this initial resistance helps
to stabilise the fork when you’re out of the saddle and cranking – like a
simplistic form of platform damping.
RockShox uses their
‘token’ spacer system to tune the air volume within the fork. The stock setup
uses two spacers and this worked well in the 100mm travel mode. Once we bumped
it up to 120mm, we felt that an extra token was required to make it softer initially
whilst still offering enough bottom out resistance. Overall we’d say that the
RS1 air spring felt more natural in 100mm format.
BIG HIT BABY
With a little bit of
stiction, you would expect the bump-eating performance to be compromised. While
I’m sure it’d eat the bumps even better if it wasn’t sticky, the upside down
design offers a clear improvement when you’re pushing the bike hard and taking
mid-to-large sized hits. A traditional fork may feel smoother in the car park, but
they tend to bind when the fork is loaded up. Much of this comes from flex in
the skinnier upper legs; when they bend the bushings no longer slide freely. With
its short inner legs and massive upper assembly, the fork is better able to
move whilst you charge headlong into the bumps. It mightn’t be as pillowy as a dedicated
trail fork but it offers excellent control for what it is – a super-light fork
that pairs well with shorter travel XC bikes.
As for the fears of
stanchion damage; our fork copped its share of knocks on the dropouts but we
only noticed one little nick on the lower slider of the fork – it was the sort
of scratch that would buff out with some fine wet and dry. Perhaps we were
lucky but we certainly didn’t treat the fork with kid gloves. If you did damage
an RS1 lower, they can be replaced individually for $159 – by comparison a
regular crown and steerer assembly is a little over $500.
PRICE 2300$
