The Motorbike Archives

Though it's not common knowledge in America, Maicos have participated in ISDT competition for over a decade. Each year, a handful of specially-prepared Maicos enter the Six Day. And each year they win an impressive number of Gold Medals. In 1976 there were 13 Maicos entered. All finished and nine took Golds. And not one was an "official" entry. Some of these ISDT bikes were prepared in off-hours at the tiny Maico factory by enthusiastic employees as private entries. Others just seemed to come out of the woodwork. The factory supplies only informal supplemental aid.

The new WR-series Maico enduro is, like their motocrossers, singular in design. It is a full-fledged ISDT/enduro racing machine with virtually no compromises. Our test bike, the WR 450, indicates Maico's determination to build a highly competitive cross-country race bike. The WR 450 blends proven motocross concepts with the accepted necessities for enduro and ISDT work. No shortcutting or cheapness has been designed in or bolted on. The WR 450 is therefore very expensive, and very much an effective enduro racer.

The WR's frame and suspension are identical to those units fitted on the Maico motocrosser. The "late-type" frame is substantially different from the older (pre-1976) forward-mount chassis. All the frame members are high grade chrome-moly tubing and plate. This material allows the Maico frame to be big, strong and light. Major changes have been made in three areas on the late-type frame: the steering head, swing-arm pivot and rear suspension attachments. The twin down-tubes are wrapped around the steering head rather than being butted against it. In an effort to both strengthen the swing arm pivot and move it closer to the countershaft sprocket center, the bolt has been mounted through a triangulated plate rather than on the frame tubing. And the pivot bushings have been replaced with needle bearings. To increase rear wheel travel, and reduce bending loads on the swing arm, the shock absorbers are now mounted in a lay-down position instead of a vertical forward mount.

As the pioneer in long travel suspension, Maico is still a half-step ahead in suspension development. The new-type fork is Maico's own design and manufacture. With 38mm tempered-steel stanchion tubes, the massive Maico fork certainly seems to be the strongest in off-road motorcycling. By placing the front axle lugs on the forward side of the cast aluminum sliders, both the stanchion tubes and lower legs can be longer. This offers more potential travel and much more stanchion tube depth into the sliders, which significantly increases rigidity. Forward-axle designs place fork masses closer to the steering head center. This reduces the pendulum effect characteristic of center-axle forks. As the fork moves (controllably or uncontrollably) side-to-side there is less inertia fighting a return back to the straight-ahead location.

Rear suspension development is a never-ending battle for manufacturers. Maico is not excepted. Because motorcycles have a limited amount of space in which to fit shock/spring assemblies, there must be design compromises with rear suspension. Shorter shock absorbers reduce weight, are not bulky and are relatively out of harm's way when fitted in a far-forward, lay-down position. However, this mounting subjects the shock to enormous working loads and tremendous fluid velocities with long travel suspension. Maico's suspension geometry places the Girling nitrogen-charged shocks at a slightly greater than 2:1 leverage ratio position. The shocks have 41/2 inches of movement and the rear wheel travel is 91/4 inches. The light-appearing swing arm places the rear axle 18 inches from the pivot center. The shocks are 12 inches from the swing arm pivot center. The upper shock mounts position the dampers at a 40-degree angle.

The 450cc engine (actually 438cc) is a simple outgrowth of the 400cc Maico. By over-boring the 400's cylinder five millimeters to 82mm, displacement was increased by 52cc. The long 83mm stroke remains the same for both engines. The 450 engine was specifically developed by the factory some years ago at the request of the American distributor who wanted it for trail and cross-country riders.

The basic mechanical layout of the WR cross-country and AW motocross engine is identical. To suit enduro-type needs, some major components are different in the WR. The piston is a Mahle casting with a single Dykes-type L-ring. Maico uses massive crankwheels which give the engine a tremendous amount of rotating inertia. The small-end bearing is a caged needle; the big end a caged roller. Single-row ball bearings support each side of the crankshaft.

The WR engines are fitted with a special right-side crankwheel that has a longer magneto shank and taper than is used in the motocrosser. This shank retains an external-flywheel Bosch CDI ignition and 6-volt 35-watt generating coil. The CDI system replaces the internal-rotor; points-controlled ignition used on the AW. The black box and high tension coil are located under the gas tank on the frame's backbone.

Maico is one of the few manufacturers that still uses roller chain in its primary-drive. The latest triple-row chain has been very reliable. The primary transmission runs directly to the main or countershaft. The chain-driven primary and semi-direct drive gearbox system are minutely more efficient than geared primary and all-indirect gearbox systems used by most manufacturers. Another important benefit of the chain-drive primary (with an enduro type bike) is the absence of gear whine and related operating noises that make passing noise tests more difficult.

The high quality of the materials used throughout the Maico is exemplified in the gearbox design. By all conventional standards the Maico gearbox assembly is dimensionally too frail. The gears and shafts appear sized for a 125cc engine. The tiny gears are half the size of transmission components found in other open-class race bikes. All of the shafts and rotating gears ride on ball or needle bearings. By using high-grade gear stock and maintaining close control over heat-treating processes, experience has demonstrated that Maico's five-speed gearboxes are as reliable as any other make. Only the Austrian-made Rotax (Can-Am) and KTM (Penton) engines might boast of greater reliability.

The clutch and shifting mechanism are peculiar to Maico. The clutch is a special design with a total of 14 steel plates. Spring tension is provided through the use of dish-shaped washers that are stacked face-to-face and back-to-back. Any number of stacking sequences can be used to alter spring tension. The shift mechanism is a carry-over from Maico's original transmission design. A trio of arms work to rotate a cam plate in the upper half of the gearbox cavity. The circular cam plate ratchets around to slide the shift forks side-to-side.

While other manufacturers have many components cast of magnesium, Maico uses the super-light alloy sparingly. Not until 1976 were any magnesium parts used on any production Maicos. The WR 450's engine castings are all aluminum. The right side crankcase half and magneto cover are special on the WR and accommodate the CDI ignition system. The rear wheel hub and front brake backing plate are magnesium. Aluminum is used for the front hub and sheet steel for the rear backing plate. All of the alloy castings are coarsely finished. Maico intentionally retains this coarse texture, giving increased surface cooling area and greater heat dissipation as the reason.

All-new on the WR 450 are the Six Day-type German "Falk Dirt Champion" plastic fenders and side panels. These components, like the chassis paint, are bright fire engine red. The color scheme intentionally makes the bike more visible—even when carrying a load of mud or dust. The side panels are fitted in place with novel plastic screws and rubber washers. Other than for cleaning, the side panels need not be removed. The large air box and splash plate, residing under the saddle, are plastic too. Air enters the intake system from beneath the seat. All of the plastic components are fuel resistant, pliable and unbreakable.

The WR 450 is the first Maico since the old round barrels (1967) that comes with an up-pipe. For cross-country use the high pipe is a must. The expansion chamber is designed for maximum torque. It has an extra-long pipe and stinger as well as a high center section. The exhaust system has two American-made components: the pipe (Wheelsmith) and the silencer/spark arrestor (Skyway).

A late-type Bing 36mm V54 carburetor supersedes the Bing 54. The V54 has a new body, slide, needle jet, needle and other components which are supposed to offer crisper performance. Previous Bing carburetors were known for their poor low-speed carburetion and short component-life. A larger gas tank retains the same odd, though not unattractive, appearance as the one used on the moto-crosser. Cut, formed and welded to shape out of flat sheet aluminum, the three-gallon tank is very basic and sanitary.

Mounted on the Akront Green Label rims are what many regard as the best tires in the dirt world—Metzelers. The front is a 3.00-21 and a 4.50-18 is on the rear. Larger spokes are not used with the Maico's conical hubs; they still demand repeated tightening for the first few hundred miles.

Maico has finally fitted their bikes with a good chain tensioner. The great distance between the swing-arm pivot and countershaft sprocket on the LTS Maico aggravates chain problems. The lower tensioner is a spring-loaded arrangement which carries a long U-shaped nylon guide. On the top of the swing arm rests another nylon section which acts as a rubbing block. This block prevents the chain from trying to cut the swing arm in half when the suspension is fully extended.

The WR's smooth, natural feel will make first-time riders anxious to roll the throttle full-open and charge the most challenging obstacles—especially uphills. The WR 450 seems to have been made to flatten hills. While its maximum power is not as great as some other big-bore enduro bikes, it finds traction like few other bikes. Higher horsepower bikes like the KTM /Penton demand concentration, mistake-proof shifts and precise throttle control to clamber over hills, accelerate around turns and power through demanding enduro section. The Maico is quite opposite. It will tolerate a lot of rider error and still power through and over obstacles without requiring down shifting, fore-to-aft body movement and exacting throttle settings. This type of power puts the WR 450 at the top of list of almost goof-proof enduro bikes.

Much of the Maico's insensitivity to engine speed, throttle setting and gear shifting is produced by the 450's flywheel inertia. The unusually large crankwheels work together with the heavy external-magneto flywheel, and all this mass, once set in motion, tends to keep rotating—external factors be damned. The engine has a great deal of compression, 12:1, which aids low-speed plonking. Though it has a flat power curve the engine will make power from 3000 to 7500 rpm.

The WR gear ratios are spaced wider than the AW, but there are no big jumps between shifts, particularly with the super-torquey engine. The smooth and effortless shifting action requires only a positive nudge from your foot—no more. Each shift is crisp and we found no false neutrals, and use of the clutch is rarely needed.

In motocross racing the clutch need only be used once by a Maico rider—off the start. In enduro use it is quite different. Tough rock sections, narrow canyons, traffic-laden uphills and other portions of any enduro course require a durable clutch. The pull required at the hand lever of the WR 450 is excessive. After three or four consecutive pulls on the clutch lever the rider's hand and fingers fatigue. Slipping the clutch heats it to the point where it will refuse to disengage. The clutch is the single weak link in the WR 450's design as an enduro bike. The engine's torque will enable skilled riders to work around this weakness but less experienced enduro riders will curse the Maico's fragile clutch.

The WR 450 suspension was specifically designed for the rigors of motocross—not high-speed cross-country riding. In these times of suspension specialization, we found the WR's suspension mismatched to fast enduro/ISDT work. At non-race speeds the Girling shocks perform well, producing a supple ride and reacting to sharp bumps properly. On high-speed roads and trails the Girlings too often allow the rear end to bottom out in G-force dips. On rippled terrain and shallow stutter bumps the rear end does not react smoothly and lets the back wheel skip and wander when under power. For enduro work, shocks with less restrictive compression damping and softer initial and stronger secondary springing would be an improvement.

The chain that is standard on the WR is a 1/4 x 5/8-inch JWS assembly. This new

JWS chain has a unique master link design that retains the side plate with a W-shaped wire rather than a spring clip.

The ISDT-type centerstand permits quicker maintenance, faster wheel changes and easier chain lubrication. The WR 450 comes with the best bash plate we have ever seen on a production dirt bike. It is a simple shovel-shaped cast-aluminum plate. The plate wraps around the frame tubes to cover the crankcases. Since it is a quarter-inch thick, the plate will not cave-in the first time the rider throws the bike belly-down on a rock or tree stump.

In refining and civilizing the Maico, the factory has taken much of the animal from the WR 450. Starting the big motor is no more demanding than required of most 175cc singles. The Bing must first be flooded with the external tickler. No choking device is included. A small lever on the handlebar actuates a decompressor valve in the upper portion of the cylinder. This lowers the cranking pressure (compression) so that the starting effort is reduced by half. When cold the engine fires on the first to third kick. It always fired on the first kick when hot. The starting effort required was so little that we asked a 118-pound woman to try to start the WR 450. She did it on many occasions with no trouble.

Trail, enduro and ISDT riders will truly appreciate the WR's low-level operating noise. The engine emits no sound at all other than a little piston clatter. There is no gear whining or internal growling from sloppy tolerances. The exhaust noise is limited to an irregular spluttering from the rubber flapper valve on the Skyway silencer. The loudest noise is the intake drone, and even that is not objectionable.

Throttle response is quick but not instantaneous like so many motocrossers. The awesome power and pipey-ness associated with the AW is not present in the WR. The engine is very gutty. It's almost impossible to feel any abrupt power surge or rush from the engine once it's off idle. The torque curve is extraordinarily flat—no sharp power peak. The engine's power characteristics are like those of a four-stroke.

The relaxed method with which the WR 450 makes power allows a rider to become almost immediately confident with the bike. Equally pleasing is the smoothness of the engine. The typically shake-desensitized off-road rider must take a moment to concentrate on vibration in order to notice it. The rubber-mounted handlebars nearly stop any low-frequency shudder at the grips. It is the smoothest running engine of all the big-bore two-stroke cross-country race bikes.

The Maico accepts riders of all sizes. Even with the nine-plus-inches of suspension travel the saddle height is not as lofty as most LTS bikes. Once you climb aboard the Maico it settles down slightly, and will permit shorter riders feet to touch the ground. Positioning of the saddle, foot pegs and bars is excellent. These features, added to the long plush saddle, make the WR 450 an exceptionally comfortable long-distance dirt bike.

The Maico fork has similar problems. It is harshly damped for initial compression and delivers a choppy ride. Fortunately there is a simple solution. By redrilling the valving holes in the damper rod (following the specifications in Wheelsmith's modification sheet) the damping of the fork can be altered. We modified the damper rods in our test bike's fork in an hour, and the improvement was considerable. The ride delivered was very smooth, cornering traction was much better, and the comfort level was greatly increased.

Going straight, through and over the worst imaginable terrain, is what built the Maico reputation. The WR 450 continues that tradition. The engine of the 450 rarely is taxed and the rider loses his sense of speed. We first rode the WR over long miles of whoop-laden trails and pot-holed roads with the impression that the WR was not working as well as it should. Afterwards our riding companions exclaimed that they were tapped-out on their cross-country bikes—and the Maico was going much smoother and straighter than their bikes. We later did side-by-side running comparisons over these nasty trails and found that the Maico would go five-to-ten mph faster than a Husqvarna or KTM open-classer before the WR would start wiggling.

The torquey engine and superb handling traits of the Maico make it an absolute delight on twisty roads. We could run really hard into turns, jam on both brakes, down-shift one or two notches and drive out of a corner in a relaxed, fully controlled slide.

The brakes are excellent. Both front and rear binders have a smooth, progressive feel but with enough pressure they will lock readily. They fade slightly when used hard but return to normal operating temperature quickly. For fire-roading the Metzeler tires are unbeatable. The only change some riders might make is to fit a larger 3.25 or 3.50 front knobby for desert use.

As with all high-strung European race bikes, the Maico WR 450 presents a few nagging irritations. The speedometer and front brake cables are stretched to their limits when the fork fully extends. They need to be an inch longer and the front brake cable should be routed through guides on the outside of the number plate. The gas cap leaks—a European standard. A sidestand should be included on the WR because the centerstand is useless in soft or wet terrain. The handlebar bend is not right: it can be set for comfortable standing or sitting, but not both. The foot pegs are terrible. They are sharp on the edges and bore through the rider's boot and instep when he's standing. When they get wet they offer no traction.

Maico's WR 450 is very expensive, very professional and, despite its faults, very pleasant. Like most dirt bikes it has its warts and imperfections. But all of them can be readily corrected—except the fragile clutch. The workmanship, design and materials are top-notch. The WR 450 is a competitive enduro bike which given proper maintenance will last. If any rider is capable of winning races, the WR 450 will get him across the finish reliably, quickly and comfortably. The big red Maico is, most of all, an absolute delight to ride or race anywhere off road.■