Dick Wilk has been around the block; his reputation as a suspension and motor guru is built on solid results and a couple of decades of practice. We’ve been race testing his modified machines (mainly KTMs) at off-road venues since the early ’90s. His most recent project involved a new Husqvarna FC450, and since Dick raced Huskys in the late ’70s, he had an inner fire to take the potent motocross machine and turn it into a dual-purpose machine: a motocrosser and an off-road weapon. And while this do-it-all modification was a run-of-the-mill project in the early ’90s, today’s off-road machines and motocrossers really are a juxtaposition of design, ideals and intent. All of the current 450 motocross machines are mean, stiff and fairly violent. There are few riders, other than top GNCC talent and National Hare and Hound pilots, who can manage the power, get the suspension to work in their arena and then fit the bike with the necessary goods to handle the long, hard world of off-road.
Dick’s goal was to be able to ride the machine off-road in the hills on Saturday, and then with a few tweaks and bolt-ons take it to the track and be competitive on Sunday. Using the same bike in two worlds would require a very broad base to the suspension settings, with the ability to alter the damping to suit the alternate universes. In terms of power, Dick had to maintain the good side of the Husky’s muscle and then be able to tone it down and work in the tighter singletrack world. Noise, tractability and output would have to be adjustable in order to handle the two segments.
FIRST, THE MOTOR
In stock form, it’s a beast that is well-appointed for moto; for off-road, it’s too much and too violent. The Husky has a switchable mode at the bars to change from max moto to controlled acceleration. For off-road, the smoother of the maps is crucial. Dick then attempted to smooth the flow of power with the addition of a Quad Flow torque wing. This device stifles turbulence at smaller throttle openings, getting rid of the jerkiness normally associated with fuel-injected butterfly-type throttle bodies. In addition, an 8-ounce Stealthy flywheel weight was added to help the chug factor and hopefully eliminate the flame-out tendencies of the MX-based engine.
The biggest change came with the installation of a Rekluse Core EXP clutch. This system offers both a manual clutch feel and a full-time auto clutch. The newest Rekluse has an externally adjustable slave located in the clutch master cylinder, allowing you to dial in the amount of gap between the pressure plate and the expandable EXP disc. The gap allows the clutch to spin freely until the desired rpm is reached for the EXP disc to engage. With the external adjustment, you can actually help dial in engine braking, engagement and clutch-lever feel.
Because the machine was attempting to bridge the world between moto and off-road, it needed an adjustable exhaust system that would work in both worlds. The FMF Megabomb header was fit for two reasons: improved bottom-to-mid power and a lower exhaust note due to the staggering of exhaust waves as they exit. Connecting the FMF 4.1 rear system allowed several options for off-road, such as a spark arrestor and quiet core system. This piece is removable—although it’s a total pain!—and without the spark-arrestor insert, the noise factor goes up dramatically! It’s too nasty for off-road, but makes really strong and broad gains for moto. Dick then installed a Twin Air screen-less air-filter cage, and this was mated to a vented airbox inlet that helped open up airflow—a necessity on the Husky.
THE CHASSIS, SUSPENSION AND DOODADS
Since the object of this project was to have one bike that could be converted from moto to off-road in minimal time, it meant we’d need two tanks, two sets of wheels and a host of other parts to facilitate the conversion. The hardest part of the equation was coming up with suspension settings that could be adjusted to work great at both disciplines.
In stock form, Dick felt that the FC suspension was harsh, even for moto. The fork is the biggest complaint, and adding to the problem are ineffective adjusters that are conveniently located but only make high-speed compression changes. So, trying to dial them in for slower speeds, rougher circuits or big mongo jumps is an exercise in futility. According to Dick, when you re-valve them softer to get rid of the harshness, they blow through the stroke and bottom. Serious measures were required.
So, Dick left the stock high-speed fork compression adjuster and added a low-speed adjuster that doubled the range of adjustability. This allowed the use of the fairly stiff valving that MX requires—without the associated harshness (since you now have the ability to dial it in). Instead of relying on insanely high oil levels to prevent clanking at full stroke, a bottoming control device was added to increase resistance in the last 2 inches of the stroke. Again, these two items not only made the forks better for moto, but they also made them adjustable enough to work properly in the off-road world. For ugly enduro-type sections, we ran the adjusters full soft with great results. The next day, a pro-level MX tester had no issues with the fork action with the adjusters set at full stiff. Naturally, all suspension setup is a compromise, but this is some of the best that we’ve used that had to deal with two entirely unique dirt bike platforms.
Out back, the stock shock does a good job for most moto circuits. Because Dick’s Racing was looking for something capable of doing double duty, the shock was re-valved to be plusher initially for off-road and stiffer as it traveled through the stroke. In addition, a stiffer spring and aluminum adjuster were added to hold up the rear end for our target rider weight of 220 pounds.
For the off-road face of the machine, the stock 21/19 wheels were replaced with some rather stunning blue/yellow 21/18 wheels made by Rad Manufacturing. Tires were Dunlop AT81s with heavy-duty tubes and EBC discs. A Dirt Tricks chain and sprockets with 13/48 gearing were chosen for both versatility and durability. Flexx bars (and handguards) were utilized for their excellent shock-absorbing qualities, an area where any big four-stroke motocrosser can see immediate improvements in hacky terrain. In addition, Fasst Company footpegs with rubber vibration dampers were installed. To reduce side-to-side wheel deflection during impacts, a Fastway steering damper was fitted. An IMS oversize tank (3.1 gallon) with fuel pump made for a quick-and-easy switch between moto and off-road. Just plug it in and go. Other off-road components included a Works Connection full-coverage skid plate, Bulletproof radiator guards, TM Designs chainguide kit, Seat Concepts off-road seat, and Shorai lightweight battery. To keep from boiling the coolant, an Evans Cooling waterless coolant replaced the stock juice.
For moto, the handguards were removed. The stock wheels were put on with Dunlop MX 52 tires. Gearing was set at 50 teeth (instead of 48). The spark arrestor was removed from the FMF 4.1 can. The stock tank was refit. The skid plate was exchanged for a glide plate, and a Seat Concepts moto saddle replaced the off-road version.
THE QUICK AND THE DIRTY
Here’s our evaluation of the mods under off-road testing and at a motocross track the following day.
The suspension: Nice job! Good cush factor at the fork, a huge improvement over stock in the off-road arena. In full-moto form, the action stiffened nicely but was a skosh soft for a jump-laden circuit. Still, it absorbed hack and never bottomed metal to metal. In the backyard, the plusher action for off-road enhanced the traction in ugly terrain and made long and tough rides easier to endure. On a moto track, the stiffer spring made it sit up nicely, and we could dial in more compression to keep it from wallowing under duress. Overall, we’re plenty impressed with the suspension.
The power: We didn’t think it was possible, but you can tame that engine (we had a KTM 450XC-F along for comparison). There is no doubt that the FMF Megabomb and 4.1 made for a smoother band of power (and less racket than the stocker), but it was the combination of the Megabomb, Rekluse Core EXP, 8-ounce Stealthy flywheel weight, Quad Flow Air wing and getting more air into the airbox via the Twin Air vent that made the package jell. There is no doubt that the taller gearing helped, too, but the total flow of power went from abrupt and serious to smooth, tractable and fun off-road. The Rekluse clutch takes some getting use to, as you honestly don’t need to cover it or even think about it when you’re riding. It does lack in decel, which can be a handful on big downhills, but both engagement and decel can be adjusted. Take the time to watch the online tutorial and spend the effort to dial it in for your needs. For straight moto, changing the gearing, yanking the spark arrestor out of the muffler, and resetting the Rekluse for less engagement made it feel more MX-like. We never did flame out or stall during either facet of the testing.
We love the Flexx bars and the Fastway steering damper’s ability to not thicken the turning but take on the offensive deflection hits. For off-road, the Rad wheels not only looked wicked, but we like an 18-incher out back. You can run lower air pressure, and this increases the traction and cushions the ride. Also, kudos to the D81 Dunlop tires; these are truly excellent off-road meats! Both of the Seat Concepts saddles hit home. The wider off-road version provided a comfy feel, while the thinner moto unit improved the fanny traction considerably (the stock Husky seat cover is awful).
We consider the Dick’s Racing Husky FC450 conversion a success. While this is an over-the-top modification piece that pushes the financial buttons quite violently, it proves that you can make positive changes and alter the DNA of your motocross machine. The goal is to pick and choose the mods that really hit home for your style of riding. Good luck! We’re all counting on you and hope you pass the audition.
Dick’s Racing 4CS fork mods: $575
Dick’s Racing shock mods: $195 + spring if required
Dick’s Racing aluminum shock spring adjuster: $85
Dick’s QFTW throttle body mods: $150
Dick’s high-flow airbox cover mod: $75
All parts available at DicksRacing.com:
FasstCo.com—bars, handguards, footpegs
RockyMountainMTVMC.com—Husky OEM parts and accessories
IMSProducts.com—3.1-gallon fuel tank
TMDesignworks.com—chainguide, disc protector
TwinAir.com—air filter, vent
Comments are closed.