KTM 350 EXC-F - Motorcycle Consumer News

KTM 350 EXC-F - Motorcycle Consumer News
Model Evaluation
“there’s no replacement for displacement,” and the KTM
makes good use of its 349.7cc to deliver fantastic grunt at low
rpm as well as snappy, high-revving power on top. Its
“enduro” cam profiles are designed to improve power across
the rev range, although they do sacrifice a small measure of
top-end power. But we sure didn’t miss it on the dyno, as
by Scott Rousseau our test unit delivered a stout 39.3 hp @ 11,750 rpm and 23.5
lb.-ft. of peak torque @ 7750 rpm, with over 20 lb.-ft. of torque
available from 6000–10,000 rpm.
The 350 EXC-F was downright surprising in our performance trials as well. Despite being delivered to us by KTM
with a 3-tooth larger rear sprocket to improve its off-road
tractability, the 350 EXC-F blitzed past our radar gun at a
very rapid 92.5 mph, 2.5 mph faster than one of our all-time
favorite mid-displacement dual-sporters, the Suzuki DRZ400S. Of course, the extra teeth also skewed the 350’s 0–60
and quarter-mile times, although it’s difficult to say by how
much because ace tester Danny Coe had a hard time keeping
the KTM’s knobby rear tire from going up in smoke while
attempting a clean launch. Our best numbers were: 0–60 in 5.4
sec., and 13.88 sec. @ 91.60 mph in the quarter mile.
After spending time on the 350 EXC-F, we certainly can’t
imagine needing more power, as it has plenty of hard-hitting
oomph from the moment you crack the throttle. Actuated by
a dual cable-operated 42mm throttle body, the 350’s Keihin
EFI delivers precise throttle response from idle to redline, and
you can lug the 350 like a diesel or spin it like a Ferrari in order
TM’S 350 SX-F is proof of a recurring concept in dirtbike
to meet the challenges of the terrain you’re traversing. By commanufacturing: that combining open-class power with the
parison, the KTM’s power delivery is far more aggressive than
chassis and handling of a 250 can yield impressive results.
that of the Husqvarna TE310 we tested in our April 2012 issue.
First conceived as a motocross engine that could deliver a comSome of the extra snap is no doubt because of the KTM’s larger
petitive, smaller-displacement open-class alternative to the
displacement, but the Husqvarna is, in our opinion, clearly the
brutishly powerful 450cc engines, it proved its value when Italy’s
more user-friendly mount for casual trail riders. The KTM feels
Antonio Cairoli rode a factory KTM 350 SX-F to consecutive
like it’s ready to compete in an AMA National Enduro or GNCC
World Motocross Championships in 2010 and 2011. There was
practically out of the crate. It may be smaller and lighter than
no question that KTM would release production versions of the
450 or a 500, but its power output demands the same respect.
350 for motocross and off-road racing, and it did in 2011, but
Our only real complaint is that the 350’s fuel injection is
for 2012 KTM has surprised dual-sport fans by introducing a
extremely lean during start-up, and attempting to fire it up can
dual-sport version, the 350 EXC-F. Score!
place extra wear and tear on the KTM’s electric starter unless
you pull the manual enrichment knob tucked behind the left-side
Engine & Transmission
portion of the 350’s low-slung 2.51-gal. fuel tank. Be warned, the
The EXC-F’s 349.7cc four-stroke motor weighs a feathery 62.8
knob is difficult to reach, and it’s almost impossible with a gloved
lbs. dry and shares roughly the same dimensions as its 250cc sibhand. Good thing that the 350 also has a manual kickstarter.
ling. Based on lightweight, sand-cast cases, it’s an efficient design
The 350’s six-speed transmission has nicely spaced ratios for
that incorporates a lot of multi-tasking, such as a counterbalancer
the most part, but just as you’d expect from a dirtbike with a
shaft that also acts as the water pump drive and jackshaft for its
license plate, first gear is very short and not of much use on the
dual overhead cam drive. The motor’s two Eaton oil pumps also
street. Shifting is delightfully smooth and effortless, though, and
share cooling and lubrication chores; the pressure pump lubriKTM’s newly developed hydraulic clutch probably deserves
cates the engine and clutch and also cools the ignition, while the
partial credit for that. Designed with a strong and light billet steel
suction pump draws oil from the crankcase and lubricates the
basket, it uses thinner steel discs and single preload-adjustable
transmission. The 350’s coolant is also partially routed through the
diaphragm spring instead of coil springs to save weight and reduce
frame to save space and reduce complexity.
clutch size—and clutch inertia. Its inner hub also features an
The 36.3mm titanium intake and 29.1mm steel exhaust valves
integrated damper. The end result is a linear feel complemented
in the 350’s cylinder head are actuated by lightweight 8mm cam
by an extremely light pull at the lever.
followers with a DLC (diamond-like carbon) coating to reduce
friction and help the motor achieve its 12,000-rpm maximum.
Of course, such stratospheric rpm is no surprise. The 350 has a
Chassis & Suspension
large 88.0mm bore and an ultra-short 57.5mm stroke, and KTM
The 350 EXC-F’s chassis is consistent with KTM’s “light
engineers focused heavily on shaving weight from the 350’s pismakes right” theme, although KTM continues to buck the aluton and crankshaft to allow the engine to rev quickly without
minum perimeter frame trend in off-road motorcycling, preferring
excessive vibration (although the crank webs are heavier to
a light yet simple chrome-moly steel mainframe and removable
smooth the 350’s power delivery).
subframe with thin-wall tubes for weight savings. KTM engiBut don’t get the wrong idea about the KTM’s rev potential. It
neers have fine-tuned the 350 EXC-F’s chassis, increasing its
isn’t some modern equivalent of a pipey 125cc two-stroke that
torsional rigidity by 30% while at the same time reducing its
will force you to fan the clutch and keep the revs above 10,000
longitudinal stiffness in an effort to make it track better through
rpm to maintain forward momentum. As the old adage goes,
off-road bumps. Its 26.5° rake and 4.29" tail are consistent with
KTM 350 EXC-F
DAVE SEARLE
Open-Class Dual-Sport, World-Class Fun!
K
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MOTORCYCLE CONSUMER NEWS
Brakes, Wheels & Tires
Reconciling the KTM’s braking performance practically
requires that we disregard our own testing numbers. Quite frankly,
60-0 braking distances requiring 162' are dismal for any lightweight motorcycle, but the blame rests solely on the KTM’s
aggressive off-road tires. Mounted on Giant-brand 1.60" x 21"
front and 2.15" x 18" rear rims connected to trick CNC-machined
hubs, Metzeler’s DOT-legal 6 Days Extreme tires are standard
equipment on the EXC-F (our test unit came with a Dunlop front
tire due to a shortage of replacement units), but their knobs offer
minimal contact with the pavement, limiting traction and feel.
Consequently, attempting fast stops on them was a futile exercise,
and the KTM’s excellent-feeling 260mm wave front rotor and
Brembo two-piston caliper only increased the difficulty by causing the fork to dive and transfer weight to the skinny 90/90-21
front tire, leaving the meatier 140/80-18 rear tire to do little more
than make skidmarks.
When ridden off-road, however, the front brake action is
superb, with plenty of power that is easily modulated without
fear of unexpectedly locking up the front wheel, but the rear
brake’s action is overly sensitive and
locks up way too easily for our tastes.
Ergonomics & Instruments
The 350 EXC-F is slim as a rail
through the middle, with a long, flat saddle that extends all the way to the fuel
filler, allowing the rider to slide forward
and weight the front end for maximum
grip in loose turns. Seat height is a tallish
37.0", but the KTM’s suspension will settle once the rider is aboard, and even our
short-legged testers had no trouble reaching the ground. Its fat, alloy handlebar is
well-placed, although some taller testers
may opt for a higher-bend for more comfort when standing over rough terrain,
and its footpeg placement is standard for
dirtbikes, with narrow, serrated pegs
that are designed for traction in muddy
conditions rather than comfort.
KTM’s digital speedometer packs a
comprehensive array of features in a
very small unit. In addition to standard
speedometer, odometer and tripmeter functions, it includes a standard clock and average speed function along with more competition-oriented attributes such as a lap timer, a mileage meter and
a stopwatch function for enduro competition. Becoming a power
user of all these features will require studying your owner’s
manual, because the instrument unit isn’t very intuitive.
DAVE SEARLE
state-of-the-art dirtbike geometry. And it’s light, too, weighing a
scant 262.5 lbs. fully fueled.
The 350 delivers supreme off-road handling, with fantastic
stability in the dirt, and its 50/50 weight bias delivers a neutral
feel with excellent turning precision on- or off-road. The 350’s
fuel tank helps to lower its CofG and, despite a substantial 12.75"
of ground clearance, the 350 can rail bermed corners or slide
predictably in loose sand or on dry hard-pack.
Alas, the 350 is no fun on the freeway, where the chassis geometry conspires with its knobby tires and unbalanced wheels (with
heavy, off-road-style bead locks) to produce an annoying thump, thump, thump as
it rolls down the road, along with an
uncomfortable headshake at 65 mph while
the front end hunts every groove and ripple. We were able to tame the headshake
some by sliding our weight back on the
seat, which loads the rear suspension and
adds a touch more rake and trail to the
front, but we can’t imagine anyone wanting to ride in that position for long. Simply
put, the more time you can spend off-road
while aboard the 350 EXC-F, the happier
you’ll be. Too bad, because our test unit
knocked down impressive fuel mileage for
such a high-performance bike, delivering
an average of 54.7 mpg—6.6 mpg better
than the Husky TE310—for a calculated
range of 137.2 miles.
The 350’s suspension specs differ considerably from its motocross and closedcourse off-road-racing sisters. While they
get WP’s latest 48mm closed-cartridge
forks and CNC-machined billet triple
clamps, the 350 EXC-F’s 48mm fork retains an old-school, opencartridge design and is secured by a cast-aluminum triple clamp.
It isn’t a cost-cutting move, rather KTM’s US officials requested
the older components after testing showed that the open-cartridge
fork is more supple in the early part of its stroke and the cast
clamp allows more flex for improved comfort on the road and at
trail-riding speeds. Out back, the 350 uses KTM’s linkageless
Progressive Damping System (PDS), which places its WP shock
absorber in a more central location on a new, lighter, cast-aluminum swingarm to reduce shock absorber-induced forces
through the chassis. The fork and shock are fully adjustable, with
the shock offering additional high- and low-speed compression
and rebound damping adjustability.
Whether pounding down rough trails or rolling along the highway, the 350’s 11.8" of travel up front and 12.5" out back delivered nearly perfect comfort and control, allowing our test riders
to take chances off-road that heavier dual-sports and/or less
refined suspension systems wouldn’t tolerate. In fact, it’s hard to
decide which aspect of the 350 EXC-F we like better, the motor
or suspension. We’ll just have to say “both.”
Attention To Detail & Value
KTM was one of the first dirtbike OEMs to tout namebrand components such as Brembo brakes, Metzeler tires
and Dutch-made WP suspension on its motorcycles back in
the 1980s, and KTM even wound up purchasing the WP factory. Those high-quality parts are still on KTMs today, and
there are other thoughtful touches as well, such as the extra
instrument features, and the PDS system, which aids ground
clearance and durability because there’s no linkage hanging
down to catch rocks or roots when the rear suspension is
fully compressed.
On the other hand, like its German neighbors to the northwest,
BMW, KTM charges premium prices for its motorcycles. At
$9499, the 350 EXC-F is a whopping $1300 more than the
Husqvarna TE310, but is its overall performance superior
enough to justify its higher pricetag? The debate could rage on
for years.
Final Thoughts
If your dual-sport adventures are composed of equal parts dirt
and street, then the KTM 350 EXC-F may not be for you. It’s an
extremely hard-core dirtbike in a dual-sport disguise. We have no
doubt that it would be competitive at a National-level off-road
event right out of the box, and that’s why we love it.
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AUGUST 2012
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Model Evaluation
Left: The EXC-F’s motocross-derived, DOHC, fourvalve, four-stroke engine utilizes an 88.0mm bore
and ultra-short 57.5mm stroke with lightened internals for snappy power and high-revving capability,
but its “enduro” cams broaden the powerband
enough to improve the 350’s versatility.
Right: While the EXC-F’s 48mm fork features “oldschool” open cartridge technology, its performance is
excellent, with 11.8” of suspension travel. Damping is
on the firm side, but it’s comfortable for all but the
most casual trail riding, and it works fine on the street.
Above: A long, flat seat allows the rider plenty of fore
and aft movement in off-road terrain but it’s no couch.
Right: The EXC-F’s 2.51-gal. gastank places much of
the fuel down low on the left side, lowering CofG.
Above left: The alloy handlebar offers plenty of leverage and a roomy cockpit feel, but taller riders may
opt for a higher bend for more comfort when standing.
Below Left: The EXC-F’s compact instrumentation
packs several neat functions, including a lap timer
and an enduro-worthy stopwatch/mileage meter.
Right: Connected to a lightweight cast-aluminum
swingarm, the EXC-F’s fully adjustable WP PDS
shock is simple yet effective, offering 12.5" of travel.
TESTERS’ LOG
I absolutely adore the KTM 350 EXC-F, but I’m also mature
enough to realize its limitations. Just a few short...well, 10...years
ago, I would’ve marveled at its engine, which has ample power to
tackle the most extreme off-road terrain, and I would’ve been so
stoked by its light, slim chassis feel, precise handling and bumptaming suspension that I could forgive any of its shortcomings.
But when I finished testing the KTM, I was flat exhausted and
my nerves were frayed. It wasn’t that it’s too powerful or unforgiving for extended off-road jaunts—its motor is snappy but
controllable, its suspension delivers an excellent ride, and its
ergos are more comfy than some off-roaders we’ve tested lately.
No, the exhaustion came not from riding the EXC-F in the dirt,
it came from riding it to the dirt. On the street its aggresssive
knobby tires lacked feel, and on the freeway they hunted every rain
groove and rut, making for a white-knuckle ride.
The EXC-F is an awesome off-road bike, but make no mistake
about it, this isn’t your dad’s old Honda XL350.
—Scott Rousseau
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MOTORCYCLE CONSUMER NEWS
I was blown away by the Husqvarna TE-310 we tested back in
April, and from what I’d read, the KTM 350 EXC-F was supposed
to be even better. But I can’t say that’s what I found.
The KTM’s vibration level was much greater than the Husky’s,
and just holding on to its buzzing handlebars was immediately
tiring. And the bars felt too low from a standing position.
Also, despite very similar specs, the KTM’s handling didn’t
strike me as precise and controllable as the 310’s, and its suspension didn’t feel as plush by comparison. Plus, I found the
KTM’s rear brake very hard to modulate—always sliding the tire.
On the other hand, the 350’s fuel injection response was perfect and more controllable than I would have imagined, and while
it has a lot more power than the TE310 (a whopping 39.3 vs
27.7hp), its more aggressive delivery makes it less “dufferfriendly.” Lastly, its lack of tire balancing (see page 48) makes
the 350 EXC-F a handful on the freeway.
Too hard-core for its street-legal role, the EXC-F is an expert’s
enduro bike in my book.
—Dave Searle
2012 KTM 350 EXC-F
SPECIFICATIONS AND PERFORMANCE DATA
ENGINE
PERFORMANCE
Type: Liquid-cooled four-stroke single
Valvetrain: .... DOHC, 4 valves per cyl.,
shim under finger follower valve adj.
Displacement: ........................349.7cc
Bore/stroke: ................88.0 x 57.5mm
Comp. ratio: ............................12.3:1
Fueling: ....Keihin EFI w/42mm throttle
body
Exhaust: ................................1-into-1
Measured top speed ......92.5 mph
0–1/4 mile ..................13.88 sec.
@ 91.60 mph
0–60 mph ....................5.40 sec.
0–100 mph ....................8.01 sec
60–0 mph ........................162.9'
Power to Weight Ratio ........1:6.68
Speed @ 65 mph indicated......63.5
DRIVE TRAIN
MC RATING SYSTEM
Transmission:........................6-speed
Final drive: ................................Chain
RPM @ 65 mph/rev limiter: ..n/a/12,000
EXCELLENT
VERY GOOD
GOOD
FAIR
POOR
ERGONOMICS TEMPLATE
DIMENSIONS
33.4"
D
N/A
50.25"
N/A
37.0"
N/A
E
52.5"
16.0"
SUSPENSION
N/A
A
B
C
47.25"
Wheelbase: ................................58.9"
Rake/trail:..........................26.5°/4.29"
Ground clearance: ....................12.75"
Seat height: ................................37.0"
GVWR: ..................................739 lbs.
Wet weight: ........................262.5 lbs.
Carrying capacity: ..............476.5 lbs.
Horizontal (nose
to) A: Passenger
seat (middle). B:
Rider seat (middle).
C: Handgrip (center).
D: Passenger footpeg (center). E: Rider
footpeg (center).
Vertical (ground
to) F: Handlebar
(center). G: Rider
footpeg (top). H:
Rider seat (lowest
point). I : Passenger
peg (top).
J: Passenger seat
(middle).
:::::
––––– Open Dual-Sport –––––
:::::
Engine
:::::
:::::
Transmission
:::::
::::;
Suspension
:::::
:::;.
Brakes
:::::
::::;
Handling
:::::
::::;
Ergonomics
:::::
::::;
Riding Impression
:::::
Instruments/Controls :::::
:::::
:::::
Attention to Detail
:::::
:::..
Value
:::::
SAE CORRECTED REAR-WHEEL HORSEPOWER
SAE CORRECTED REAR-WHEEL TORQUE, LB. FT.
Front: .WP 48mm male slider forks w/
adjustable preload, comp. and reb.
F
GH I J
damping, 11.8" travel
::::;
OVERALL RATING
:::::
Rear: ..WP monoshock, w/adjustable
MISCELLANEOUS
preload and 2-stage adjustable
DYNAMOMETER DATA
comp. damping and reb.
:::::
Instruments: ......Digital speedometer, Low end
•
damping,12.5" travel
odometer, dual tripmeters, clock, Mid-range :::::
39.32 hp
BRAKES
trip computer functions, enduro Top end
:::::
mileage meter
Front: ....Single 260mm rotor, Brembo
KTM’s high-winding 350
•
two-piston floating caliper Indicators: .... t/s, low fuel, EFI/trouble
EXC-F motor makes good
on its promise to deliver
Rear: ..............................220mm disc,
light, high beam
23.56 lb.-ft.
big power in a small
Brembo single-piston floating caliper MSRP: ......................................$9499
package. With cam proRoutine service interval:........1200 mi.
files that broaden its
TIRES & WHEELS
Valve adj. interval: ................2400 mi.
powerband, it belts out
plenty of low-end grunt
Front: ........90/90-21 M/C 54R Dunlop Warranty:............1 year, 12,000 miles
and enough top-end power
D908F on 1.60" x 21" wheel Colors: ................Orange/Black/White
for all-out competition.
RPM, THOUSANDS
Rear:..140/80-18 M/C 70M Metzeler 6
Days Extreme on 2.15" x 18" wheel
TEST NOTES
STANDARD MAINTENANCE
ELECTRICS
Time
Parts
Labor
PICKS
Item
Battery: ................................12V, 5Ah
: Amazing, open-class power from just 350cc
Oil & Filter ................0.5 ..........$31.90+9.06 ..40.00
Ignition: ..............................Electronic
: Handles like a true off-road racer in the dirt
Air Filter....................0.3 ..........$31.49 ..........$24.00
Alternator Output:......................168W
Valve Adjust..............1.5 ..........$22.79 ........$120.00
: Suspension works well on the dirt and the street
Headlight: ..........................35W/35W
Battery Access ..........0.5 ............MF ..............$40.00
PANS
Final Drive ................1.0 ................................$80.00
FUEL
R/R Rear Whl. ..........0.5 ................................$40.00
: A dirtbike with license plates, it’s barely streetable
Tank capacity: ......................2.51 gal.
Change Plugs ..........0.25 ..........$14.99 ..........$20.00
: Brakes lack power and feel for short pavement stops
Fuel grade: ..........................91 octane
Synch EFI..................1.0 ................................$80.00
: Unbalanced wheels and knobbies are sketchy on the road
High/low/avg. mpg: ......55.7/53.6/54.7
Totals
5.55
$110.23
$444.00
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AUGUST 2012
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