BMW 300 (Isetta)
From BMW Tech
|Also called||BMW Isetta|
|Automobile layout||RR layout|
|Internal combustion engine||298cc cc single cylinder 4-stroke (53 mph (85 km/h) top speed)|
|Transmission (mechanics)||4 speed manual|
In October 1956 the Isetta Moto Coupe DeLuxe (sliding-window Isetta) was introduced. The bubble windows were replaced by longer, sliding side windows. The engineers had enlarged the single cylinder to a 72 mm (2.8 in) bore and 73 mm (2.9 in) stroke, which gave a displacement of exactly 298 cc, and at the same time they raised the compression ratio from 6.8 to 7.0:1. In this way the engine now generated 13 hp (10 kW) at 5200 rpm, and the torque rose to Convert/Nm at 4600 rpm. The maximum speed remained at 85 km/h (53 mph), yet there was a marked increase in flexibility, chiefly noticeable on gradients.
In addition to the quest for better performance, there was another reason for the change: it was then still possible to drive the 250 cc Isetta with the old Class IV driving licence. Quite a number of Isettas were lovingly maintained by their owners for years and even decades, precisely because they possessed no other licence. On the other hand, from 1956 onwards, first-time drivers had to pass the test for Class III if they wanted to drive a car. True, the Class IV licence continued to be issued, but it was only valid for small motorcycles.
A second, similar reason for fitting the larger engine was the prevailing tax regime. The 250 cc engine did not take full advantage of the tax class, which then went up to 300 cc.
- ↑ "1957 BMW ISETTA (300)". Lane Motor Museum. http://lanemotormuseum.org/show_vehicle.php?veh=BMWISETTA300C1957.
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|Microcar||Isetta 250 / 300|
|Small family car||600||LS/700|
|Compact executive car||3 Series||340/340-2||1602/2002||E21||E30|
|Executive car||5 Series||327||1500,1800,2000||E12||E28||E34|
|Luxury vehicle||7 Series||501/502||E3||E23||E32|
|6 Series||503||3200 CS||2000CS||E9||E24|
|Sports car/Grand tourer||M1, 8 Series||E26||E31|