FOUR-STROKE 500CC MOTOCROSS SHOOTOUT

Pick up the May issue of DB and you’ll be treated to an in-depth comparison of the four-hottest four-stroke Mxer?s on earth. Here’s the short version:
Anyone with more dirt bike knowledge than Al Gore knows that Yamaha rewrote the book on four-stroke motocross bikes with its YZ400F and, now, world-champion YZ426F. The blue beast is so effective, right out of the crate, that the other Japanese companies have been shocked into complete silence. Picture an ostrich with its Shoei’d head sticking into a big berm. A shivering ostrich. Well, Europe isn’t afraid to meet this challenge head-on – after all, motocross started in the Old Country on four-stroke machinery, and thumpers have all but ruled the 500 MXGP?s in the ’90s.
Sweden and Italy, in particular, have fueled the four-stroke revolution. When Cagiva bought Husqvarna and offered the Swedish thumper engineers landscaping jobs, Husaberg was formed out of spite, and the Italian/Swedish rivalry was on. The Vertemati Brothers developed Husabergs in the GP?s then had a falling out with the Swedes and formed their own marque (which later was renamed VOR). Though it’s a long and twisted tale, the result of this corporate and nationalistic battle is not one, but three, new-generation, 500cc thumpers capable of hanging with the YZ426F. Those would be the lightened and refined Husaberg FC501, the all-new KTM 520SX and the VOR 503MX. These puppies can hang, but can they beat the YZF? Drop the gate!

HUSABERG WHEELIES
* High ignition setting is way fast
* Low setting good for waning laps
* Good high- and low-speed cornering
* Quality chain, rims, handlebars
* Good stabilty in whoops, ruts

HUSABERG FLAME-OUTS
* No low-end power, stalls easily
* Although easy starter, lever awkward
* Tank wide in front, hampers cornering
* Throttle hard to twist, controls heavy
* Too much compression braking

KTM 520SX TECH INSPECTION
* Automatic (and manual) decompression
* YZ-esque pumper FCR Keihin carburetor
* Four-speed, moto-only transmission
* Undamped clutch hydraulically controlled
* More narrow ergonomics than KTM 250SX
* WP inverted fork and PDS shock

KTM 520SX WHEELIES
* Mountain-leveling power and torque
* Light weight with very neutral handling
* Ridiculously easy to start, even in gear
* Thin ergonomics and light controls
* Linkageless shock provides great hook-up
* Perfect amount of compression braking

KTM 520SX FLAME-OUTS
* Not as responsive down low as YZF
* No hot-start system for falls/stalls
* We got it to headshake occasionally
* Suspension is soft for full-moto
* Demand greatly overpowers supply
* Needs a fifth gear for GPs/desert

YAMAHA YZ426F TECH INSPECTION
* Five-valve, DOHC short-stroke
* Highly-adjustable Kayaba suspension
* Aluminum, D-tube subframe saves a pound
* Larger clutch and stronger rod/crank
* Hot-start integral with FCR2 pumper carb
* Stronger frame, stretched ergonomics

YAMAHA YZ426F WHEELIES
* Snappy throttle response, great jetting
* Clutch feel, action and quick-adjust perch
* Handling and power dare you to go faster
* Strong brakes with excellent feel at levers
* Nothing lacking in total package, stock
* Plethora of GYT-R hop-ups and accessories

YAMAHA YZF FLAME-OUTS
* Clutch perch ‘hidden’ by protruding decompressor
* Chain and handlebars could be higher-grade pieces
* Although a revver, doesn’t pull on top like 500s
* Taller seat foam would improve ergonomics
* Heavy damping and overall weight noticeable

VOR TECH INSPECTION
* Long-rod, SOHC engine
* Gear-driven cam
* Bolt-together frame
* Magnesium cases
* Cassette gearbox
* Backward kickstarter
* Forged 3-piece swingarm

VOR WHEELIES
* Hydraulic clutch is excellent
* Unusual, but easy to start
* Big power is controllable
* High quality chain, bars & parts
* Optional height seats

VOR FLAME-OUTS
* Too much engine braking
* Harsh fork has lots of stiction
* No in-gear starting or hot-start
* Old-world ergos and handling
* Wide, boxy ergonomics package
* Leaks more oil than a Panhead Harley

RATINGS AND CONCLUSIONS

What we have here are two big thumpers that beg you to go faster every lap and two thumpers that dare you (with threats of bodily harm) to go faster. The Yamaha YZ426F and KTM 520SX are heads and shoulders above the Husaberg FC501 and VOR 503MX in every performance category and in price. For $7098, the Husaberg should have a higher degree of refinement, lower vibration and better carburetion and ergonomics. At $7750, the VOR 503 should have the best suspension ever to grace a dirt bike, in-gear starting, no vibration and its own trophy girl. Should have but doesn’t.
Even if the VOR cost the same as the Yamaha, it wouldn’t deliver the goods on the track. Few testers went slower on the Husaberg than they did the VOR, for fear of swapping into something immovable. As for the ‘Berg, we expect a $7098 dirt bike to at least keep running as we approach turns. You have to pull in the clutch and rev it to keep from stalling, when you should be thinking about lines, passing and such. If you buy a Husaberg or VOR, plan on even more for suspension revalving.
On the other hand, the YZF and KTM are well worth the money…and wait. We’re especially impressed with the KTM 520SX. Its power is perfect, and it’s wrapped in an effective, slim chassis with excellent suspension. It takes a bit more effort on really technical, supercross-infested tracks than the YZF, but its awesome engine makes it a playbike that pegs the fun meter. Only the four-speed transmission holds the 520SX back for GP and desert work. Also, availability is scarce, so you might not be able to find a 520SX until the 2001 production run. Unless we were full-on supercross guys, we’d take the KTM over the YZF, even with a $700 larger pricetag.
Hardcore moto-heads don’t want to wait, though. They want to win right now. Unless you’ve got an inside line to a KTM dealer or regional rep like Guy Cooper, you’ll probably end up on a YZ426F. That’s fine. You’ll be on a level playing field with the one or two 520SX pilots in your area…and the hordes of 426 riders.

OVERALL POWER
1. KTM 520SX
2. Yamaha YZ426F
3. VOR 503MX
4. Husaberg FC501

STARTING EASE
1. KTM 520SX
2. VOR 503MX
3. Yamaha YZ426F
4. Husaberg FC501

OVERALL ENGINE
1. KTM 520SX
2. Yamaha YZ426F
3. VOR 503MX
4. Husaberg FC501

FORK RATINGS
1. Yamaha YZ426F
2. KTM 520SX
3. VOR 503MX
4. Husaberg FC501

SHOCK RATINGS
1. Yamaha YZ426F
2. KTM 520SX
3. Husaberg FC501
4. VOR 503MX

OVERALL HANDLING
1. Yamaha YZ426F
2. KTM 520SX
3. Husaberg FC501
4. VOR 503MX

ERGONOMICS
1. Yamaha YZ426F
2. KTM 520SX
3. Husaberg FC501
4. VOR 503MX

CONTROL PACKAGE
1. KTM 520SX
2. Yamaha YZ426F
3. VOR 503MX
4. Husaberg FC501

WHERE TO GET IT:
Husaberg Motorcycles USA
1119 Milan Ave
Amherst OH 44001
(216) 244-6301

KTM Sportmotorcycle, USA
1119 Milan Ave
Amherst OH 44001
(216) 244-6301

Yamaha Motor Corp.
6555 Katella Ave.
Cypress, CA 90630
(714)761-7300

VOR MOTORI USA
8468 Loma Place
Upland, CA 91789
(909) 608-0082