2. Engine

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It's Different

The Nimbus 'C' engine has a number of unique design features. Perhaps the most obvious one is the exposed valve train, with the inlet and exhaust valve springs open to the elements. Perhaps the second feature of note is that it is a four cylinder in-line, air cooled engine with overhead valves and camshaft. Considering the engine went into production in 1934, this was quite advanced for the time period. The displacement is 746cc (on stock bores and pistons).

The engine is fascinating to watch when it is running - it has a unique sound, and I could watch the valve train for hours. Of course, as this is an air cooled engine, and set length-wise in the frame, even when moving cooling is not great so prolonged idling is not recommended ! Below are a few photos of the engine as received.

At the moment, the plan is to not restore this - just maintain it. There are a few engine issues - a broken bolt and oil leaks mainly - but they are not critical and so can be addressed down the road.

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