DON`T LET WEAK SUSPENSION RUIN YOUR RIDE

sUsPENsIoN
UPGrADEs
DON’T LET WEAK
SUSPENSION RUIN
YOUR RIDE.
HERE’S HOW TO MAKE
IT WORK FOR YOU.
WORDS: JusTin fiVella
John mcGuinness pancakes his
suspension en rouTe To anoTher lap
record around The isle of man.
PIC: pacemaker press
W
ith its nice lines and great motor, the Suzuki Gladius is quite
a good bike. It’s got all the right moves, save for feeble
suspension that’s so soft it not only wallows in the corners
but bottoms over freeway expansions. The stock suspenders and rear shock are such a letdown they overshadow the rest of the
stellar package.
But the Gladius isn’t alone; in fact, most modern motorcycles can use
a little help in the suspension department as well. We chose the Gladius
because it epitomizes this two-wheeled epidemic.
“Unless you’re talking about an expensive sportbike with top-drawer
parts, most bikes can use a few suspension upgrades—especially the
bargain bikes like the Gladius,” Erick Hilton of Race Tech suspension said.
When it comes to improving your suspension there are two methods;
the expensive route of replacing the forks and shock with aftermarket
SBKP-101000-TECH.indd 61
units and the more economical path of suZuki Gladius
upgrading the internals of your stock
pieces like we did on the forks of the
Gladius.
“No matter the type of riding you’re
doing, whether it’s strictly street, all
track or a mix of both, your stock
suspension can be tailored to your
riding style,” Hilton said. He also went on to explain that sportbikes
tend to start with better equipment and oftentimes just need the
internal pieces like the springs and valves upgraded. But on bargain
bikes, especially ones with cheap rear shocks, sometimes a switch to
a better unit is necessary since the stock hardware is too diminutive
for spirited riding.
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8/16/10 6:31:08 PM
Suspension Upgrades
Suspension 101
CARTRIDGE
T
Here’s a quick brush-up on how the various suspension components function
before we show you how they affected our Gladius test mule.
Forks
Damper-Rod
D
DAMPER ROD
COMPRESSION
STROKE
amper-rod forks (DRF) are most-commonly
found in traditional fork layouts, with the larger
lower legs and skinny upper ones. DRF are also
commonplace on older bikes and lower-cost examples like the Gladius, because they are cheaper to
manufacturer.
In essence, DRF regulate the speed of fork travel
by moving a damper rod with a piston through
the damping oil as the fork compresses. The drag
created by the oil passing through the holes in the
piston creates a rudimentary damping effect.
Since DRF only have one mechanism to deal with
both low-speed damping like brake dive, and highspeed damping like hitting an expansion joint on the
freeway, it can be difficult to excel at both.
Conversely, if the holes on the damping rod are
made big enough to cope with high-speed bumps,
they lose their low-speed compression capabilities
and tend to bottom under low-speed compression situations like braking. On the
flip side, if the holes are too small they work well for low-speed compression but
can’t flow oil fast enough for high-speed compression.
In essence, there’s no perfect set of DRF from the factory, but they can be vastly
improved with aftermarket pieces from Race Tech.
CARTRIDGE
FORK
COMPRESSION
STROKE
he second set of common forks
are called cartridge style and
they can come as a standard style
orientation or as an upside-down
unit that has the thicker, outer legs
at the top and the smaller, inner
legs near the bottom. This setup offers far more rigidity than conventional forks.
Cartridge style forks regulate fork
speed by using a damping piston
with bendable shims stacked up
against the face of the piston (like a
roll of quarters inside a toilet-paper
tube). When the oil flows through
the damping piston at slow speed,
the shims deflect (bend) and let
the oil flow around the edges for
good low-speed compression.
Yet when a high-speed bump is
encountered, the shims deflect even
more to achieve great high-speed
compression properties. Cartridgestyle forks give you soft low-speed
damping with great high-speed
action because they have linear
damping rates.
Shocks
Gas-Emulsion
U
nless you’re riding a bike from the old
days, your shock likely uses a combination of oil and nitrogen to dampen the
bumps. When dampers repetitively move
they create heat; when the two combine,
the oil begins to foam, which hinders the
shock’s ability to dampen the bumps. The
nitrogen helps prevent the damper oil from
foaming by regulating the oil pressure inside
the shock.
The feeble rear shock on the Gladius is better
suited to a mountain bike than a sport cycle!
62
Remote
Reservoir
W
hen stepping up to
a remote reservoir shock it not only
increases the amount
of oil used in the shock,
but it also allows the
manufacturer to run a
separate bladder for
the nitrogen inside the
reservoir. The increased
oil capacity and larger
remote nitrogen bladder
work together for better
cooling properties and
increased stabilization of
the oil pressure.
SSB ★ OCTOBER 2010
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8/16/10 6:31:10 PM
SuSpenSion upgradeS
suspension 101
A DIFFERENT
ROUTE
Fork UPGrADEs
DampER-ROD
M
any bikes have DRF and can benefit from an upgrade. Our Gladius
got Race Tech HP fork springs. Not only are the HP springs made
to tighter tolerances, but they’re wound for whatever rider weight/riding style you select–in our case we jumped to stiffer springs.
Along with the springs we added Race Tech’s Gold Valve Cartridge
Emulators. These bits are tunable valves that sit between the damping
rod and the spring to control the compression damping, essentially
acting like cartridge forks.
The emulator works like a cartridge style fork in that it lets oil pass
through a small hole for good low-speed damping. When the oil flow
increases for high-speed damping, the shim opens and lets the oil
quickly pass through.
In addition to adding nearly independent high and low speed damping adjustability, Emulators turn progressive DRF damping characteristics into linear damping curves. This means that the damping rates
won’t increase with fork speed, one of the weak points to DRF.
Lastly, fork-oil weight can be adjusted to help tune rebound damping
since oil weight has the most effect on the rebound action of a fork.
CaRTRiDGE FORKS
C
artridge forks can also be upgraded with better oil and springs.
To take it one step further, Race Tech also offers high-performance Gold Valves to tune both your compression and rebound
damping. When it comes to complete adjustability, nothing beats
a cartridge fork, and you can take your stock sportbike forks to
race-spec levels.
The small race Tech sTicker means biGGer and
beTTer ThinGs are happeninG inside The forks,
Which TranslaTes inTo a more sTable, easy To
conTrol moTorcycle.
64
SSB ★ OCTOBER 2010
SBKP-101000-TECH.indd 64
shock UPGrADEs
L
While the Race Tech fork
upgrades are a great,
cost-effective addition to
the front of the Gladius,
out back you have yet another affordable alternative—a GSX-R600/750
shock. Without much
modification you can
add a late model GSX-R
shock to handle the rear
suspension duties.
ike forks, you can also upgrade the
oil, spring and valves on your stock
shock. By upgrading the hardware on
your shock you can cut the compromises in search of the perfect blend of
adjustability. But in some cases, like
the Gladius, the stock hardware just
isn’t up to the task. Not only is the
stock shock completely overpowered,
but it offers nothing more than preload
adjustability.
Race Tech ditched the factory crap in BUYER’S BOX
favor of its G3-S shock. This beauty is
RACE TECH SUSPENSION
the crown jewel of the Race Tech line
racetech.com
and is fully customizable. “You can get
a G3-S custom fit to whatever type of (951) 279-6655
riding you’re doing and it’s independently adjustable, too,” Hilton said.
“ALL NEW” GLADIUs?
A
back-to-back comparison on the stock and Race
Tech-prepped Gladius reveals two distinctly different bikes. Where the stocker was harsh and hardly
composed at speed, the Race Tech example is far more
sporting; taut over bumps but composed at speed.
Post suspension upgrades, the Suzuki no longer dives
heavily under braking and absorbs freeway expansions.
It now has a firm feel like a proper sportbike.
Moving toward the aft side of the Gladius, the G3-S
shock also did wonders as it transformed the bike from a
wallower into a more composed and confident sportster.
Damping action is on the stiff side, but the payoff is great
suspension action at speed and commendable ride quality on the daily commute.
While the price of admission for the Race Tech overhaul
might seem a little steep, considering the fact it transformed this little hauler into a corner carver, it’s easily
worth the money. If you can’t fork over the money in one
lump, start with the fork upgrades, then look at the base
G3-S shock and later add the remote reservoir. In a year
or two you’ll have the streetbike you’ve always wanted—
one that’s fast in the corners and supple on the street.
8/16/10 6:31:12 PM