Air Filter Maintenance

If you only maintain one thing religiously, make it this. Dust and sand ingestion is the single biggest cause of premature engine wear off-road — and it's completely preventable.

How often to check it

• After every single ride in dusty or sandy conditions — not "every few rides".
• At least every ride in general, even in cleaner conditions — it takes two minutes.
• Immediately if the bike suddenly feels down on power or runs rich/rough.

Cleaning it properly

• Wash with a dedicated foam air filter cleaner (not petrol — it degrades the foam over time).
• Let it dry completely before oiling — trapped water plus oil clogs the foam and reduces airflow.
• Use a proper foam filter oil, worked in evenly by hand, then squeezed (not wrung) to remove excess.
• Too little oil doesn't trap dust; too much restricts airflow — a light, even, tacky coating is the target.

Fitting it back correctly

More engines are damaged by a badly seated filter than by a dirty one. Check the seal around the entire edge of the filter cage — any gap is a direct path for unfiltered dust straight into the engine. A thin layer of filter grease on the sealing lip helps it seat properly and stay put.

Signs your filter (or its seal) has failed

• A sudden, unexplained loss of power.
• Visible dust inside the airbox or intake boot.
• Rapidly climbing oil consumption or oil that looks gritty at the next change.