STI ROCTANE XD
; A few months back we brought you
a sneak peek of the new Roctane radial tire from STI. That was a massive
piece of rubber at 30 inches tall. It was
so big, we had to make modifications
to the fenders on our RZR just to get
them to fit without a lift kit. Well, STI
does offer the Roctane in some more
down-to-earth sizing, and recently we
were able to spend some serious tor-ture-test time with them.
On this go-around, we chose to test
28x10-14s on all four corners of our RZR
XP Jagged X. This machine comes
stock with 26x12 Maxxis Bighorns. Cars
like this RZR 4, Wildcat 4 and soon-to-be-released Maverick 4 do well in most
wide-open situations but fall short in
others. With such a long wheelbase,
these machines get high-centered
more than a two-seater does. So to
improve upon the already-great
Jagged X car, new, taller tires would
hopefully be a solution.
The Roctane is sort of a cross
between an ITP Blackwater and a
Maxxis Bighorn. It has an eight-ply
rating, deep lugs that wrap around to
the sidewall and is non-directional.
This pattern is available in a size
range from 25 inches all the way up to
32 inches for 12- and 14-inch rims. A
massive rim guard helps keep the tire
An eight-ply radial that is almost bulletproof
By the staff of Dirt Wheels
on and keeps rocks from damaging
your wheels. Weight is average for
this size tire, at right under 30 pounds.
The STI brand is actually owned by
huge tire distributor MTA, so you
know your dealer either stocks them
or can get them in a matter of hours.
Companies like PureOffRoad.com list
this size Roctane for $150 each.
The sizing we chose worked out
perfect. We mounted the new meats
on a set of STI HD1 machined wheels.
The 28s do not rub under normal trail
conditions. We only had them rub on
the right front once when we dropped
off a steep rock ledge with the steer-
ing wheel slightly turned. With the
help of power steering, the wider front
tires didn’t hinder any movement. In
fact, they helped the front of the car
grip the ground and turn much better
than with the stock tires.
On hardpacked conditions, the
tires were smooth and provided
plenty of traction for stopping or
acceleration. They didn’t wander or
hunt. In the sand, it was more of the
same. Floatation was good, and the
tires stayed exactly where we pointed them. And out of the sand, we
pointed them right at the sharpest
stuff we could find. Bounce was minimal, and feedback through the
steering wheel was consistent. On
the smoother, rocky trails, the tires
absolutely gripped like glue. We
could air down from 15 to 5 psi and
claw up and over anything. After a
100-mile test, we didn’t even have a
hint of a puncture and could hardly
see wear marks.
The STI Roctane is a great all-around tire from a growing company.
We expect to see a tire like the
Roctane make its way onto some new
machines as standard equipment in
the near future—they are that good.
Check out more of what they have to
offer at www.stitireandwheel.com. ;
Roctane has aggressive
lugs that wrap around to
the sidewall. Although
the STI HD1 wheel doesn’t do it any justice, the
Roctane does have a
thick rim guard that will
help protect lesser
wheels and most beadlock rings.
The first fix we’ve made
to the Jagged X RZR is
to make it taller. The 28-
inch STI Roctane tires
keep it from getting
high-center on slow,
rocky trails. Traction is
great in loose and
sandy conditions too.