Table of contents
motorcycles
Racing boxers from then and now
Racing boxers from then and now
Go, Siggi, go
Did Siggi Guttner really stay ahead with the good old BMW RS? In any case, the two won the race against the passing of time.
Ralf Schneider
04/04/2002
The old lady is not acting ladylike. She stands there and rages. A little helpless, with plugged ears, Markus Barth, Boxer Cup driver, Siegfried Guttner, MOTORRAD works driver for decades and the author, are bracing themselves against the sound pressure eruptions of a BMW RS 54. One of the legendary vertical shaft RS from 1954, that one warms up. You stand as if in heavy surf, carried away. They breathe the castor odor that escapes the BMW megaphones in ring-shaped clouds like the air of a health resort. This scent of burnt Castrol R 40 infects you with the most beautiful illness you can have as a motorcyclist: racing fever. Symptoms? Involuntary turning movements of the throttle hand, autistic concentration on motorized single-track vehicles.
No wonder that Siggi fidgety fiddles with the chin strap of his Cromwell, almost knotting his fingers when pulling on his gloves. He only calms down when he holds the RS on the handlebars, which he confidently leans towards him with every throttle. Anyone who only thinks of the back torque of a lengthy, massive crank drive has understood nothing. Admittedly, the way in which the back-torque is put in and out moves the machine, which weighs only 140 kilograms, when shifting around the longitudinal axis, is not gentle. But one of those peculiarities that make the RS difficult to drive. In the end, only Walter Zeller got along really well with her, who also achieved his and her greatest success with the Vice World Cup in 1956. But so be it, Siggi and the RS disappear amid a fulminant roar in the Hockenheim forest. It takes Markus to press the starter button on the cup boxer and drive behind. He, too, with a bearish, bassy growl. He sits on the faster motorcycle, has adhesive tires, a stiff chassis and almost twice as much power as Siggi. But today, the old woman made it clear to him, he is only second. No matter how fast it goes. After all, the RS drove in real GP races, while its Cup-R 1100 S was only allowed to appear in the supporting program.
Nevertheless, he carefully kneads the tires warm and begins to systematically study the machine, which is still unknown to him. How much braking torque can the hindquarters withstand when shifting down, how does the Telelever feel when braking in an inclined position? He slowly gets faster, then he drives the cup boxer out of the first chicane with wildly pumping hindquarters. Siggi has also found the timing for the gear changes, avoids the range below 6000 rpm, in which the RS only mocks, and lets it fly.
Then he has to refuel. The RS gets a seven liter mixture of aviation fuel and super plus. “Des Modorradle is fine,” he says, “I turn it up to 8000, but actually I want it to go higher.” But he does not agree with the driving behavior. In the curves it “shakes” him properly, and the front duplex brake rubs more than it brakes. Then it climbs up again, lets itself be pushed until the BMW emits a cloud of racing perfume, and indulges in being shaken again with pleasure.
In between, Markus takes a break and looks at how elegantly Siggi circles the RS through the curves. He is also satisfied with the engine and praises the Metzeler Rennsport, with which the Boxer Cup is being driven this year. He was particularly fond of the front tire because he was the stocky one R 1100 S. makes it easy to handle and transmits enormous braking forces. “However, brutal braking doesn’t do much. You have to let this motorcycle run through the corners with momentum, ”he states in an increasingly louder voice, without taking his eyes off the approaching Duo Siggi / RS, who demonstrate exactly this driving style.
When the racing bug epidemic peaks, everyone drives everything. Siggi the cup boxer steadfastly at an angle with his knees on the tank and Markus the RS, in whose 35 Dellorto carburetors he gets caught when he tries to spread the knee on the inside of the curve. The author is allowed to and has the same problem at the beginning. And that about shaking, everyone agrees, is not so harmless. In the waves of the east curve, the RS begins to stir vigorously, an obliquely driven over edge in the asphalt greets with a start of handlebars. It is decided not to smile at the finely locking friction damper on the steering tube any longer, but to use it. “They were real men who drove this thing fast,” says Markus. For a moment he doesn’t seem sure if he is one himself. One can understand this doubt.
And learn once again that the temperament of an engine has nothing to do with absolute performance. 54 measured RS-PS from 500 cubic centimeters can ignite a fire on the slopes as well as the 104 PS of the cup boxer. In addition, it is good to experience the mechanical components of the soundscape from a position in front of the exhaust outlets. The grinding of numerous spur and bevel gears, the ticking of the rocker arms on the valve stems, which otherwise only appears when the engine continues to run for a short time after the ignition has been switched off. The modern boxer, on the other hand, is a mechanical Mister Nice-Guy who has been deprived of the robustness and liveliness of his ancestor.
When the vertical shaft motor has cooled down a bit, Siggi lets the aggressive fuel out of the carburetors. Then he loosens four screws and pulls the right valve cover. A magical moment. At first glance you can see what was to be expected with a very down-to-earth precision. The upper bevel gear of the vertical shaft, its counterpart on the exhaust camshaft, the small spur gears, which transmit the rotary motion to the intake cam. And the eccentric rocker arm axes for adjusting the valve clearance, fixed with a finely toothed disc and its counterpart. But some things are different here. The rocker arm bracket is not made of gray cast iron, but is milled from solid, the cams operate the rocker arm via rollers. Well, many have retrofitted the dual ignition, but the other one? Up to the five-speed transmission. “I think you should talk to a bush on the phone,” says Siggi and pulls out a piece of paper with a number. With who? With Dieter Busch, the tuner who prepared the engines for the six-time team world champions Enders / Engelhardt. He also repaired this engine after a crankshaft failure. And reveals its secret. Here, now crackling quietly, is a factory engine from 1960. One of the rare short-stroke engines with a 64 millimeter stroke and a 70 mm bore. And cylinder heads that Ludwig Apfelbeck built. With an adapted combustion chamber cap, modified valve angles and modified rocker arm kinematics that increase the valve lift to ten millimeters at the inlet and nine at the outlet. Hence the milled bearing blocks and roller rocker arms. Hence the boxer’s bite. Everyone is deeply impressed and silent while loading the motorcycles. And now finally thank the owner of the RS, Willi Marewski, for the ride on this very special example of an already special motorcycle.
Related articles
-
Sport: Kreidler van Veen 50 cc racing machine
Nakamura motorcycles Sport: Kreidler van Veen 50 cc racing machine Sport: Kreidler van Veen 50 cc racing machine circular saw Content of If you want to…
-
Tuning and restoration for BMW two-valve boxers
markus-jahn.com 25th pictures Stefan Wolf 1/25 BMW dealer Karl Maier (57). Jahn 2/25 Pressing: After a bath in liquid nitrogen, the valve guides are…
-
146 hp boxer from alpha Racing
Pesamosca accesories 146 hp boxer from alpha Racing 146 hp boxer from alpha Racing at INTERMOT The finest cylinder head tuning alpha Racing uses a valve…
-
Motorcycle racing in New Zealand Horst Saiger
Saiger / Doug Cornes 20th pictures Saiger / Doug Cornes 1/20 Horst Saiger accepted the official invitation to the Suzuki series, … Saiger / Doug Cornes…
-
motorcycles Derbi GPR 125 Racing test Derbi GPR 125 Racing test The Bringer Thomas Schmieder 11/30/2004 The Ducati driver said hello and so did the VTR…
-
motorcycles Roberts racing machine Roberts racing machine Formula three Are three cylinders enough to win a 500cc Grand Prix? Old master Kenny Roberts…
-
Norton back in racing: Comeback at TT 2022
Cathcart Sports & scene Motorsport Norton back in racing: Comeback at TT 2022 Norton wants to go back to racing Comeback at the TT 2022 The British…
-
Motorcycle racing on the ski slope
r-photography.info 19th pictures Rossen Gargolov 1/19 The Snow Speed Hill is floodlit fun. Rossen Gargolov 2/19 Impressions from Snow Speed Hill in…
-
Fathers and sons in motorcycle racing
2snap 13th pictures 2snap 1/13 Peter Ottl already supported his son Philipp in the Red Bull Rookies Cup. 2snap 2/13 In 2016, Philipp Ottl experienced his…
-
Motorcycle fair in Milan EICMA 2021 Presented by Jorg Kunstle Sports & scene Motorsport The topic of racing at EICMA The topic of racing at EICMA A…