Speak French and a Zündapp KS 750
This holiday proved it once again: If you speak French, then a holiday in France is extra fun. We met a scratchy old man with a unique collection. Last year there were six more visitors to his 'museum', which cannot be found on the entire Internet. The man therefore has no computer / address.
But all that visit became too busy for him. So he no longer received visitors. But we had heard his name in the village and arrived in a BX. And we spoke French well. Moreover, the charm of my Lief the collector did not escape. I could have exchanged her on the spot for a half-track.
But there was also a Zündapp KS 750 combination. And it was certainly not for sale or exchange.
Already in the years leading up to World War II, the Wehrmacht realized that there was a need for a light, off-road vehicle that could be used for reconnaissance assignments as well as the rapid transport of people. So a kind of 'Jeep'. Motorcycles, especially sidecar combinations and tricycles, had already proven their worth during the First World War. After extensive preliminary work, the Wehrmacht commissioned both BMW and Zündapp to develop a military sidecar combination, which had to meet a number of specific requirements:
* The maximum payload had to be 500 kg, and that was the weight of three soldiers with their weapons, ammunition and packing.
* The cruising speed had to be 80 km / h and a top speed of 95 km / h
* The minimum speed of 4 km / h was required to keep pace with marching troops.
* The required tire size was 4,5 × 16 inch (the tires were interchangeable with those of the KdF-Wagen and the Volkswagen Kübelwagen)
* The required ground clearance was 150 mm and there should be room in the mudguards for snow chains
BMW already had experience with heavy boxer engines from 1921 and has been producing head valves since 1925. Only in 1933 did Zündapp launch its first boxer engines, developed by Richard Küchen and his brother Xaver. After an internal company conflict, Richard Küchen had switched to DKW in 1934. Ernst Schmidt had then further developed the boxers into front-enders. The successful KS 600 was his child's. Küchen had already shown during WWI that he had nothing to do with working for the army, but he was transferred back to Zündapp by the government to work on the new Wehrmachts spanning.
Customization was required
The 600 cc Zündapp KS 600 turned out not to be adaptable to the book of requirements. It turned out to be faster to start a new design from a blank sheet of paper. Already in 1939 the first two prototypes were made available to the army command for tests. These were 700cc models, where the cylinders were each 5 ° higher in order to obtain sufficient ground clearance. The final version would be 751 cc large.
Soon the Zündapp KS 750 turned out to be considerably better than the BMW R 75
BMW was commissioned to build the Zündapp KS 750 under license, but refused that order. BMW was then instructed to take over the sidecar wheel drive designed by Küchen, the hydraulic braking system and the wheels. Moreover, BMW and Zündapp were forced to make as many parts as possible interchangeable. Ultimately, this policy ensures that 70% of all newly produced BMWs and Zündapps consist of standardized parts. Production of the KS 1941 began in the spring of 750. The machine was delivered to the army, the air force and the Africa Corps.
An almost boxer engine
The engine was a two-cylinder head valve boxer engine mounted on 751 cc with two valves per cylinder. To increase the ground clearance, the cylinders were slightly 'raised', making it an '170 ° boxer'. The cylinder heads were made of aluminum and, together with the valve covers, were well equipped with cooling fins, in order to also obtain sufficient wind cooling at very low (mars) speeds. All bearings were rolling bearings. The camshaft drive and the oil pump drive were done with gears from the crankshaft.
The tricycle had only one carburetor, a Solex BFR30 carburetor, which was adjusted for the KS 750 so that the engine continued to run at a large slope. Magnetic ignition was used to prevent problems with the battery. Yet there was a lead-acid battery on board: it was placed behind the left-hand cylinder.
They have become expensive things
The Zündapps are now more than sought after. Therefore they are not very cheap anymore. Think of amounts between 40.000-50.000 euros for a nice copy. The parts supply is good because many parts are made new again.
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