Mechanical Knowledge Flashcards

Before every journey, what checks should a motorcyclist complete as part of the POWDERY or T-CLOCS check?

Answer: Tyres, controls, lights, oil, chassis and sidestand (T-CLOCS) — or petrol, oil, water, damage, electrics, rubber, yourself (POWDERY)

Pre-ride checks using a structured mnemonic cover all safety-critical systems: tyres, lights, fluid levels, controls, brakes and the rider's own fitness — a disciplined habit that prevents many breakdowns and accidents.

What is the effect of over-tightening the steering head bearings on a motorcycle?

Answer: Creates 'notchiness' in the steering, reduces manoeuvrability and can cause the bike to fall into a straight line rather than steering through corners

Over-tight steering head bearings restrict the steering to a preferred straight-ahead position; the bike may resist steering inputs and tend to fall upright, increasing the rider's workload and reducing safety.

Engine braking is used on a motorcycle by:

Answer: Closing the throttle and progressively downshifting through the gears — the engine's compression resistance slows the bike without using service brakes

Engine braking uses the resistance of the engine against compression to slow the motorcycle; used with progressive downshifting it is particularly effective on long descents, reducing heat buildup in the service brakes.

What does a 'weeping' fork seal (small oil leak from the front fork) indicate the rider should do?

Answer: Have the seals professionally replaced before the leak worsens and contaminates the brake disc

Even a small fork seal leak will worsen; oil on the brake disc causes sudden and severe brake failure, making prompt professional seal replacement essential for safety, not merely maintenance.

Why is the tyre valve cap important on a motorcycle tyre?

Answer: It maintains the valve core seal against dust and moisture that can cause slow deflation — loss of pressure on a motorcycle is much more dangerous than on a car

The valve cap prevents dust and moisture from contacting the valve core; a defective valve can leak slowly; even a small pressure loss on a motorcycle significantly affects tyre profile and handling.

What symptom indicates that a motorcycle's shock absorbers (rear suspension) may be worn?

Answer: Excessive bouncing that does not dampen quickly, diving under braking and an uncomfortable wallowing sensation through bends

Worn dampers allow the suspension spring to bounce freely without controlled damping; the result is a bouncing, imprecise rear end that reduces tyre contact consistency and cornering stability.