Tech feature: SRAM unveils Force and Rival road components, April 6,
2006
SRAM jumps in with both boots
Rivals to feel the Force as road newcomer unveils two new groups?
Component maker SRAM has carved itself a sizable niche of the mountain
bike market by offering a viable alternative to dominant player Shimano.
Last year the Chicago-based company announced that it would add road parts
to its line-up in 2006, and at Sea Otter it has unveiled finished versions
of two road groups: Force at pro level and Rival for less lavish budgets.
James Huang takes a test ride.
SRAM’s new top-end Force
road component group
|
SRAM has officially unveiled details of its highly anticipated road component
packages, to be released around mid-year. Two complete groups will be
offered: Force is intended to be a pro-level kit to compete with Shimano's
Dura-Ace and Campagnolo's Record while Rival will offer consumers a more
economical alternative that will be similarly priced to Shimano's Ultegra
but - SRAM says - with a 200g weight advantage. Each group will include
its own set of shifters, front and rear derailleurs, crankset, brakes,
cassette, and chain but will retain full cross-compatibility with each
other.
Shifters
Force and Rival share a wealth of new technology, the most important
of which is SRAM's DoubleTap method of shifting. Up until now, integrated
road brake/shift levers have typically incorporated two separate levers
in order to actuate shifts in both directions. DoubleTap, however, enables
riders to initiate both upshifts and downshifts with a single dedicated
lever as
we described in an earlier article.
Ergonomics was a key factor
|
|
During prototype testing,
Ben Jacques-Maynes
|
|
The Force rear derailleur
|
|
Force marks SRAM’s first
|
|
The new road cassette
|
|
SRAM’s dual-pivot Force brakeset
|
|
Our Force test group
|
|
The mid-level Rival shifters
|
|
As with the shifters, the
Rival rear derailleur
|
|
Both of SRAM’s new road front
derailleurs
|
|
Rival marks the first use
of hollow forging
|
|
Rival’s cold-forged dual-pivot
brake arms
|
|
A single swing of the lever can
shift one smaller cog at a time or up to three larger ones. Shifter throws
are impressively short, and both shifters utilize fully internally routed
cables for a tidy appearance. The Force shifters will feature a carbon
fiber main lever with a magnesium secondary for a total weight of just
305g per pair. The Rival shifters will use aluminum for both the brake
and shift levers for a slightly heavier weight of 335g.
Derailleurs
As expected, SRAM has carried over some of the features of its MTB rear
derailleurs to the road versions. The new derailleurs use what SRAM calls
Exact Actuation cable pull ratio. This requires more cable movement than
competing systems in order to actuate a shift, but not as much as on SRAM's
mountain systems, resulting in a more robust setup that should be more
tolerant of cable friction or slight misadjustment. While this bodes well
for long-term and all-weather performance, it does, however, mean that
SRAM's new rear derailleurs will not be compatible with either Shimano
or Campagnolo levers. The top level Force rear changer will include a
carbon fiber pulley cage and magnesium inner parallelogram plate that
reduces the weight to only 174g. Rival will use a more conventional aluminum
pulley cage and inner link but still will only tip the scales at just
190g. Both rear derailleurs will handle up to a 27-teeth rear cog.
SRAM has wisely designed the new Force and Rival front derailleurs to
be fully compatible with either standard or compact chainrings, the latter
of which is becoming increasingly common. A proprietary cable pull ratio
is also used here as well (again, signaling a lack of compatibility with
existing components) and both front derailleurs will be available in braze-on
style with additional clamps required for band-type mounting. Both Force
and Rival front derailleurs use a steel cage and aluminum construction
for weights of 88g in braze-on version, and 102-103g for the clamp version.
Cranksets
Both Force and Rival cranksets will wear the SRAM brand name rather than
SRAM's chainset brand Truvatuiv, to give a common identity to all the
the new road components. The Force crankset features a new one-piece integrated
carbon fiber crankarm and spider while Rival will see SRAM's first hollow
forged aluminum crankset. Both will use the proven GXP external bearing
bottom bracket from Truvativ. No triple chainring versions will be available
initially, but both Force and Rival will be offered in a standard ring
configuration (53/39T) as well as two compact varieties (50/36T and 50/34T).
The Force crankset with bottom bracket will weigh in at 780g while Rival
will, as you might expect, come in a little heavier at 820g.
Cassettes and chains
SRAM will debut a wholly new style of cassette for the road groups rather
than carry over its previously ubiquitous PowerGlide shift gates and ramps.
Rather than simply shave down or shape teeth, the new OpenGlide technology
removes complete teeth from smaller cogs in order to speed up shifts,
particularly under load. Intuition would suggest that this would result
in premature cog wear, but these smaller cogs typically don't experience
much torque unlike larger cogs which generally undergo much higher load
(that is, unless your nickname includes the word 'Jet' or 'Super'). For
now, SRAM will only be introducing one cassette for both groups, OG-1070.
This cassette will include an aluminum carrier for the largest three cogs
and an aluminum lockring, and will be available in 11-26T, 12-26T, and
11-23T flavors. The 11-23T version will weigh 220g.
SRAM has also updated its chains for Force and Rival, and the new PC-1090R,
PC-1090, and PC-1070 chains will all feature SRAM's new PowerLock connecting
pin as well as hollow pins in an ultra-narrow 5.9mm width that should
be compatible with all currently available 10 speed drivetrains. Chain
weights should come in around 265g (for 114 links).
Brakes
SRAM chose to use cold-forged aluminum construction for the Force and
Rival brakes for its appealing combination of light weight and durability.
Both brakes feature a stiff, triangulated geometry and strong return springs
provide a snappy lever feel. Cartridge-style pads with angular adjustability
will be used on both groups. The Force version will use titanium for the
pivot bolts and hardware for a weight of 279g per pair while the stainless
steel bits on Rival will add a marginal amount of mass, bringing the total
to 295g for the set.
Out on the road
The weather was looking particularly dicey during our short stay in Carmel,
but somehow SRAM managed to open up a perfectly timed window of clear
and sunny weather for a three hour long test ride of the new Force group
along the Pacific coast.
SRAM directed an enormous amount of energy towards perfecting the shifter's
ergonomics during the group's development, and the results of that effort
are plainly obvious. True right-hand and left-hand specific asymmetric
'fighter pilot' hood shapes immediately fit noticeably better in my hands
than current offerings, and the outward cant of the brake levers fell
naturally at my fingertips. In addition, the pivot axis of the shift paddles
themselves is tilted by 15° to more closely approximate your fingers'
natural movement and the paddle is equally accessible from either the
hoods or the drops.
Acclimating to the DoubleTap style of shifting was more of a mental exercise
than anything as the new shifters represent a wholly new method of changing
gears. Not only am I used to having two shift levers, each of which moves
the derailleur in just a single direction, but the DoubleTap shifting
produces TWO clicks for just a single downshift (one to disengage the
upshift pawl, and another to actually wind the cable spool). Moreover,
the use of the single paddle combines the movements of both STI and Ergopower.
Regardless, adaptation to the new style was fairly quick, provided I
remained conscious of how the shifters were supposed to work. I certainly
did mis-shift a handful of times during the first couple of hours on my
Eddy Merckx test bike, but working the new DoubleTap shifters became quite
natural by around hour three. Racers, however, will want to put more time
on them prior to use in competition to ensure that they can use them properly
in the heat of battle.
Like SRAM's off-road shifters, the Force shifters provided a reassuring
amount of audible and tactile feedback when changing gears. Shifts were
impressively fast, solid and precise. It is difficult to say if SRAM's
new OpenGlide cassette cog profiling actually sped up shifts in the affected
gears, but the bike did shift well under full load.
The front shifting worked quite well, also, but is a bit quirky. Unlike
the other systems out on the market, SRAM's DoubleTap shifter has no trim
position for the large chainring. The derailleur cage position can, however,
be trimmed when in the small ring, but SRAM engineers say the cage profile
does not require there to be two positions for the large ring. Admittedly,
there was no rubbing in the 'big-big' combination, but this was arguably
the biggest hurdle to cross in terms of adaptation.
As for the other components, it is impossible for me to comment on the
stiffness of the crankset as I was riding the Merckx for the first time
and had no frame of reference. SRAM claims the new crank is stiffer than
their previous top road crank offering, and I'll just have to take their
word on it.
Although the rain mostly held off during our ride, there was more than
enough water either standing in or flowing across the road to adequately
test the wet weather performance of SRAM's new pad compound. As predicted,
the pads did seem to compromise just a bit of dry weather grip, but wet
weather performance was surprisingly good. Overall power and modulation
were both impressive, and the rigid brake caliper arms produced a solid
feel at the lever.
Quirks
SRAM's new Force group was not without its minor quibbles. The reach
to the levers was short enough to accommodate most small hands out there,
but the brake lever itself could possibly stand to be just a hair longer
for easier access from the drops. The short reach also didn't leave much
room behind the levers for other fingers when braking while resting on
the hoods, but it wasn't an unreasonably tight space and I never actually
pinched my fingers. More importantly, downshifts that are attempted if
you are already in the largest cog out back can inadvertently result in
an UPSHIFT depending on setup. Due to how the shifter internals function,
a short push of the lever first disengages the cable spool, but since
there is not a lower gear to which to shift in that situation, there is
no choice but to release the lever and upshift one gear. This is largely
another mental hurdle to overcome (and it can apparently be alleviated
with careful setup), but it's one thing to consider as you're entering
the red zone during a hard climb.
All in all, though, SRAM has done an extraordinary job of developing
a wholly new pair of road drivetrains from scratch. While not quite perfect
yet, it's amazingly close in both function and finish, plus there are
still a handful of refinements that are yet to be integrated into the
final production. At the very least, though, the components are polished
enough for both the Kodakgallery.com/Sierra Nevada teams and Team Orbea
to race on the complete kits this weekend at the Sea Otter Classic, many
of whose riders will be using the groups for nearly the first time. We'll
reserve final judgment on SRAM's efforts for our full production test
kit, but for now, things are looking good.
|