The Honda CB750 is an air-cooled, transverse, in-line-four-cylinder-engine motorcycle made by Honda over several generations for year models 1969–2008 with an upright, or standard, riding posture. It is often called the original Universal Japanese Motorcycle (UJM) and also is regarded as the first motorcycle to be called a "superbike".
1969 Honda CB750
Dick Mann's Daytona-winning CR750 on display at Le Musée Auto Moto Vélo, a transportation Museum in Châtellerault, France
The 1980-1983 CB750C "Custom" would become the basis for the Honda Nighthawk line of motorcycles.
1982 Honda Nighthawk 750SC
A straight-four engine is a four-cylinder piston engine where cylinders are arranged in a line along a common crankshaft.
Diagram of a DOHC straight-four engine
1989-2006 Ford I4 DOHC engine with the cylinder head removed
2006-2009 Nissan M9R diesel engine
1908–1941 Ford Model T engine