Knowledge Centre

A practical guide to Harley-Davidson® final drive belts, covering belt inspection, correct tension and alignment, common damage, pulley condition and when a drive belt may need replacement.

A practical guide to Harley-Davidson® motorcycle spark plugs, including plug types, heat ranges, correct gaps, installation and what spark plug condition can reveal about an engine.

A practical guide to Harley-Davidson® motorcycle air filters, including how they work, disposable and reusable filters, high-flow air cleaners, Stage 1 upgrades and when tuning may be needed.

A practical guide to what is inside a Harley-Davidson® motorcycle oil filter, how filter media, bypass and anti-drainback valves work, and why choosing the correct filter matters.

An independent guide to choosing an aftermarket exhaust for a Harley-Davidson motorcycle, covering slip-ons, full systems, 2-into-1 and dual layouts, sound, performance, Stage One upgrades, tuning, UK road-use considerations and common buying mistakes.