KTM 640 LC4 Adventure R

KTM Adventure 640
Manufacturer	KTM
Also called	Adventure R640, Adventure R 640, 640 LC4 Adventure R, LC4 Adventure 640, 640 LC4 Adventure, 640 Adventure
Production	1999 - 00
Engine	Four stroke, single Cylinder. SOHC, 4 Valve per cylinder,
Compression ratio	11.0:1
Ignition	Contactless DC-CDI ignition with digital advanced system, KOKUSAN
Spark Plug	NGK DPR8 EA-9
Battery	12V 8Ah, maintenance free
Transmission	5 Speed, claw shifted
Frame	Central chrome-moly-steel frame
Suspension	Front: 50 mm WP upside-down forks Rear: WP monoshock
Brakes	Front: Single 300mm disc, 4piston floating caliper Rear: Single 220mm disc, 1 piston floating caliper
Front Tire	90/90 - 21 54S Enduro 3
Rear Tire	140/80 - 18 70R Enduro 3
Wheelbase	1510 mm / 59.4 in
Seat Height	945 mm / 37.2 in
Weight	154 kg / 340 lbs (dry),
Fuel Capacity	28 L / 7.4 US gal / 6.2 Imp gal
Manuals	Service Manual

Engine

The engine was a Liquid cooled cooled Four stroke, single Cylinder. SOHC, 4 Valve per cylinder,. The engine featured a 11.0:1 compression ratio.

Drive

Power was moderated via the Wet, multiplate.

Chassis

It came with a 90/90 - 21 54S Enduro 3 front tire and a 140/80 - 18 70R Enduro 3 rear tire. Stopping was achieved via Single 300mm disc, 4piston floating caliper in the front and a Single 220mm disc, 1 piston floating caliper in the rear. The front suspension was a 50 mm WP upside-down forks while the rear was equipped with a WP monoshock. The 640 LC4 Adventure R was fitted with a 28 L / 7.4 US gal / 6.2 Imp gal fuel tank. The bike weighed just 154 kg / 340 lbs. The wheelbase was 1510 mm / 59.4 in long.

Photos

Overview

KTM 640 LC4 Adventure

Inspired on the much bigger, Paris-Dakar winning motorcycle (KTM 990 Adventure), the 640 Dual Sport motorcycle presented by KTM retains only the good features such as versatility, agility, power and gets reed of the unnecessarily weight and size, resulting in an easy to ride all around motorcycle with plenty of power coming from the LC4 single-cylinder engine which proved successful on many KTM models (the Duke, SMC, LC4).

During the time I’ve ridden KTM’s 640 Adventure I saw a new face of motorcycling and I sure loved it. Attraction immediately came as I jumped onto its seat and fired up the four-stroke 625cc single-cylinder motor. The riding position

is perfect for medium sized persons, just like me, and the exhaust note is deep, making the rider well aware of where the rpm level is all the time.

Putting the bike into first gear doesn’t involve

any fatigue and the clutch feel is firm and precise. Having

ridden KTM bikes fitted with the same engine, I was now expecting a quick go coming from the single-cylinder, but I must say that throttle

response, although immediate, was tuned towards trail riding so it is a bit smoother and reassuring.

The engine is enough powerful

for almost anything that the off-road will require:

climbing steep hills, passing through

rivers, and spreading dirt. You name it and the 52 horses at 7000 rpm will deal with, problems excluded. It will also be the result of a torquey engine (55 Nm at 5500 rpm) which provides all of the tractable

power that gets you out of trouble and very often impresses

your buddies. I had no problems taking the 640 Adventure in deep mud and then wash it as I passed the river (my feet were already wet and the boots needed to be cleaned anyway,

so what better method?).

Also out on the trails I managed to get the front wheel off the ground by suddenly

twisting the throttle and it was quite a pleasure to do this as the terrain ahead presented

many step-like bumps. Impressive pull

saves the day!

But this type of exploitation

also requires good-performing suspensions and

the WP front and rear units are more than suitable for the job. I did not manage to reach the fork’s bottom end more than two times and that happened while landing

from an ambitious and optimistic

jump above a thick log.

The front brake played a trick on me (or I may have played a trick on the front brake) on wet grass surface,

determining the front wheel to slip and the rider to taste some muddy grass. It is more of a talent thing than efficiency

as you have to calculate how much to pull the lever, taking in consideration

the fork compression and the grip of the surface you’re on. I guess that this is why I’ve never seen an off-road rider

with no broken bones. On normal, street use, the performance Brembo brakes which

apply their pistons on two 300mm discs up front and a single 220mm disc at the rear prove very efficient

and confident-inspiring. I preferred using

both brakes because I didn’t wanted to taste the asphalt (I reckon that this ride report would have been published

pretty late). Even so, it is steady and confident under powerful braking.

I’ve taken the bike down the freeway and up to 80mph so I would get a feel of those harsh

vibrations that tend to make customers avoid it and I must say that evolution

has clearly said its word and even though

present through the handlebars and

footpegs, the vibration levels are acceptable and easy to live with. Would you preferred the engine’s grunt to fade away concomitant

to the rpm

increase? I don’t think so.

Conclusion A wonderful mix of power, versatility and

fun is what makes the 640 Adventure Traveller’s Edition a true blast each time you ride it. Prepared for the long run on and especially

off the road, the bike is a true representation of KTM’s dedication on

delivering the best performing and

one of the

most agile all-around motorcycles on

the market today.

Make Model	KTM 640 LC4 Adventure
Year	1999 - 00
Engine Type	Four stroke, single Cylinder. SOHC, 4 Valve per cylinder,
Displacement	624.6 cc / 38.1 cu in
Bore X Stroke	101 x 78 mm
Compression	11.0:1
Cooling System	Liquid cooled
Induction	Mikuni BST 40
Ignition	Contactless DC-CDI ignition with digital advanced system, KOKUSAN
Spark Plug	NGK DPR8 EA-9
Battery	12V 8Ah, maintenance free
Starting	Kick & electric
Max Power	35.7 kW / 49 hp @ 7500 rpm
Max Torque	52 Nm / 5.3 kgf-m / 38.4 lb-ft @ 5500 rpm
Clutch	Wet, multiplate
Transmission	5 Speed, claw shifted
Primary Drive Ratio	30:81
Gear Ratios	1st 14:35 / 2nd 15:24 / 3rd 18:21 / 4th 20:19 / 5th 22:18
Final Drive Ratio	16:40
Final Drive	Chain
Frame	Central chrome-moly-steel frame
Front Suspension	50 mm WP upside-down forks
Front Wheel Travel	300 mm / 11.8 in
Rear Suspension	WP monoshock
Rear Wheel Travel	320 mm / 12.6 in
Front Brakes	Single 300mm disc, 4piston floating caliper
Rear Brakes	Single 220mm disc, 1 piston floating caliper
Front Tire	90/90 - 21 54S Enduro 3
Rear Tire	140/80 - 18 70R Enduro 3
Steering Head Angle	62.5o
Wheelbase	1510 mm / 59.4 in
Ground Clearance	320 mm / 12.6 in
Seat Height	945 mm / 37.2 in
Dry Weight	154 kg / 340 lbs
Gvwr	380 kg / 839 lbs
Fuel Capacity	28 L / 7.4 US gal / 6.2 Imp gal
Fuel Reserve	3.8 L / 1.0 US gal / 0.8 Imp gal
Manual	blackbears.ru

External Links

• http://www.blackbears.ru/manual/files/KTM_400-660_LC4_'98-03_Repair_Manual.zip