The anatomy of a British classic

Expect every classic, British or otherwise, to have its idiosyncrasies. But there are general points which are relevant to any British bike.

1. CHASSIS Mostly steel, either a simple cradle or a central spine with the engine hanging from it. Norton’s iconic Featherbed was so-named due to its sumptuous ride quality, and there are two types: Wideline means wide frame rails at the seat, Slimline means narrower. A ‘rigid’ frame has no rear suspension; ‘plungers’ have limited vertical rear-wheel movement; and ‘swingarm’ means the wheel is held in a trailing arm controlled by shock absorbers. Some bikes use their frame tubing to act as the oil tank for the drysump engine.

2. GEARBOX Pre-unit construction means the engine and gearbox are separate. All pre-1970s British bikes had a right-foot change and most are four-speed. Some are one-down/three-up, while others are one-up/three down.

3. CARBURETTORS British bikes added performance by adding extra carbs. So a Triumph Tiger 650 had one carb, whereas a Bonneville had two. Simple.

4. ENGINES Is it clean, relatively oil-tight and running quietly? A muted rustle is fine – clunks and knocks are not. You want smoke-free when warm and no petrol leaks from the carbs. Most are dry sump with a separate oil tank.

5. ELECTRICS Take a multimeter. essential checks to carry out are: does the battery charge, and do all the lights and indicators work?

6. BRAKES Drum brakes are classified by the number of leading shoes. Put simply, the more shoes the better you stop, but with increasing complexity of set-up.