Zundapp 125 Enduro
ZUNDAPP 125 ENDURO
CYCLE WORLD ROAD TEST
A Semi-Finished Six-Days Replica That Keeps Pace On The Street As Well As In The Dirt.
THE ZUNDAPP NAME has long been associated with off-road competition. Earlier Zundapps based on the highly successful 200-cc Challenger and 250-cc Super Saber two-strokers won many trials and scrambles events both in the United States and in Europe. Many high placings were also earned in the International Six Days Trial, the premiere event of its type in the world.
Up until a couple of years ago, however, the Zundapp name had faded from the scene when problems, both at the factory in Western Germany and at the United States distribution network, made the machines hard to get, and even harder to maintain.
Zundapp's first big comeback into this country was made a few years ago when McCormack International Corp. began bringing in their 125-cc competition machines with a frame manufactured in England by Sprite, and powered by a Zundapp 125, under the brand name of American Eagle. These tough little machines ran fast, handled well and won many races. With the demise of the McCormack firm, parts again became scarce until Steen's Inc. picked up the ball.
The Zundapp line is now being distributed by Rockford Motors, even though several frame manufacturers, including the Rickmans, are using Zundapp powerplants.
In what is obviously a concentrated effort by the factory in Germany to produce a really "professional" enduro machine, they have almost come up to expectations. A few minor annoyances detract from what would otherwise be the finest "out-of-the-crate" enduro machine in its class.
Basing the Enduro on the 123-cc "square" (54/54mm bore/stroke ratio) engine makes it a potential winner from the start. Highly reliable, compact and light in weight, the 125 Zundapp engine can best be described as "bulletproof." Vertically split crankcases, for example, feature cast-in fins for additional cooling and strength. The crankshaft has each full-circle flywheel supported by a hefty ball bearing, and the long right-hand mainshaft is supported at its outer end by still another ball bearing assembly in the outer cover. The connecting rod's lower end is separated from the crankpin by roller bearings. At the top we find needle bearings supporting the piston pin.
The two-ring silicon-alloy piston moves up and down in a hard-chromed liner, which is shrunk into the generously finned aluminum alloy cylinder. The most obvious advantages of this process are less chance of piston seizure and improved wear. On top is the unusually finned "Sunburst" cylinder head which provides excellent cooling and pleasing looks.
A 26-mm Bing concentric carburetor has replaced the earlier, somewhat leaky and troublesome Bing carburetor with a bolt-on float. Besides leaking, the earlier carburetors had a tendency to flood easily, and more than one float dropped off in the heat of competition because of a loose nut. The concentric, however, has none of the bad faults of the earlier models. A tickler button is retained, in addition to a handlebar lever-operated choke control, making starting easy even in the coldest weather. A plus factor of the concentric is its ability to deliver fuel to the engine even if the machine is leaning over on its side.
Following conventional two-cycle practice, the 25:1 mixture of fuel and lubricating oil is mixed with air in the carburetor and drawn down into the crankcase where the oil lubricates the connecting rod, main bearings and the piston/ cylinder walls before being burned and expelled through the exhaust pipe. Lubrication of the primary drive, clutch and transmission is handled by a common reservoir.
Helical gears transmit power from the crankshaft to the robust clutch silently, although there is no shock cushioning device in the clutch hub. Rather, a series of rubber blocks mounted in the rear wheel is used to ease the load on the transmission and chain. Five moderately spaced ratios and vastly improved shifting action over earlier models make the new transmission a joy to use. Gone are the missed shifts and generally indecisive feel of the shift lever, but the inordinately long lever travel is still there and takes getting used to. The overall gear ratio is a little "tall" for anything but street riding, although swapping to a 14-tooth countershaft sprocket or, perhaps, a 50-tooth rear sprocket (in place of the standard 15-tooth counter and 46-tooth rear sprockets), would make the machine much easier to ride in the dirt.
Ignition and lighting duties are handled by a flywheel magneto/generator mounted on the left end of the crankshaft. A small six-volt battery for the horn and lights nestles under the seat, right in front of the aircleaner assembly.
A lightweight, double-cradle frame of tubular steel is very strong with liberal gusseting around the steering head and swinging arm pivot. The swinging arm itself is a hefty 1 7/16-in. in diameter and looks like it would never bend. An innovation is the rubber front engine mount, which provides extra support and reduces the engine's vibration to a pleasant level. Earlier Zundapp Enduros had only a bottom and rear mounting for the engine.
With the exception of a few items, the general layout of the bike is perfect. Wide, motocross-type handlebars with a welded-in crossbar and Magura control levers sit atop a beautifully machined aluminum top triple clamp. The front forks, which provide six inches of travel, were pretty stiff initially, but loosened up quickly after an hour or so at Saddleback Park. External gaiters protect the fork tubes from flying rocks and dust, although the fork springs are mounted internally. After several hours of hard riding, only a trace of oil seepage appeared at the bottom of the gaiters. We were a little disappointed with the limited amount of steering angle, however, which makes taking slow, sharp corners a touchy business. Another 10 deg. of steering angle is needed. Rear suspension is by non-adjustable Boge shocks which originally seemed as though they would lack rebound damping and be too soft. We were pleasantly surprised to find them superb both in comfort and control.
Another gripe is the seat. It's fairly high off the ground at 33 in., but considering the machine's 10 in. of ground clearance, that doesn't seem so bad. Until you sit on it. Well padded it is, but it curves mysteriously upward at the front near the gas tank, and instead of becoming narrower, it gets wider, forcing the rider's legs apart instead of allowing him to rest his knees against the tank for best control. Its saving grace is that it's sloped upward at the rear, which comes in handy when climbing hills.
Exhaust systems have rarely been a strong point with the Germans, and the Zundapp Enduro is no exception. Because the front of the engine is rubber-mounted, the exhaust header pipe is a slip fit into the exhaust manifold, and the rear of the muffler unit (which contains an as yet unapproved spark arrester) is rubber-mounted, but no attempt was made to tuck the pipe in close to the engine where the rider's leg has to be when his right foot is on the footpeg. Hence, only the outer one-third or so of the footpeg can be used to plant his feet, and he has to consciously turn his toe inward by quite a bit to actuate the rear brake pedal. The only redeeming feature of the muffler, besides the spark arrester, is its sound level, which is very low.
Another potentially weak point are the wheel rims. Past experience shows that these steel units are weak and tend to bend easily when bashing through the rough with low tire pressures. The Enduro also lacks rim locks to keep the tires from creeping around on the wheel rims and pulling out the valve stems.
The brakes, however, are excellent, and appear to be quite waterproof. Only moderate lever pressure is needed to bring the bike to a stop, and there is no tendency for either wheel to lock up while negotiating steep, downhill sections in the dirt.
The front fork brace on earlier Zundapps was also a trifle weak, but ours did its job with no signs of flexing or cracking.
One more dig: the speedometer fitted to our test machine was a front-wheel-drive unit, which is necessary for enduro work, but it didn't have a trip-meter!
Commendable features of the Enduro include the aircleaner arrangement. The carburetor air intake is connected by a pleated rubber hose to a huge plastic airbox under the seat. On top of the airbox is a dry-paper element aircleaner which is accessible by turning the plastic top piece a quarter turn. Providing the magneto is properly sealed, the Zundapp will run with the engine unit completely submerged!
A neat naugahyde cover snaps around the entire underseat area to prevent the ingress of foreign matter, and this cover even has a piece of asbestos cloth sewed onto it behind the muffler to prevent heat damage. A high quality toolkit fits into a plastic tray just behind the aircleaner element, and the seat is easily removed by pulling out a spring-loaded peg on each side and lifting up and rearward.
Despite our criticisms, the Zundapp was fun to ride. The engine's output increases rapidly from mid-point in the rev range. It's definitely "peaky," but not "pipey." That is, not much power is available at low engine speeds, but the power comes on strongly and smoothly. The near ideal weight distribution gives almost neutral handling over bumps, and the well planned steering geometry allows one to cover fireroads and rough motocross-type terrain at a high rate of speed. With the exception of the protruding muffler, either a sitting or a standing position is very comfortable, and the 10-in. ground clearance permits riding over logs without fear of hanging up the frame. A lightweight aluminum bash plate, though, would be a good piece of standard equipment to help protect the underside of the engine, as repairing or replacing the crankcase assembly could prove costly.
The Zundapp Enduro is a semi-finished gem of a motorcycle, waiting for its owner to add the touches necessary to make it one of the most desirable machines in its class. [O]
ZUNDAPP
125 ENDURO
