• PSA: Stock airboxes often pass dirt and cause serious engine damage (Pictures)

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 #10637  by Travis @ Buggy Depot
 Sun Jul 16, 2017 8:43 pm
If you ride in the dirt, check your intake tract for dust and debris before your next ride.

I see customers' carburetors looking like this again and again.
This area is supposed only see 100% filtered clean air only.


The cause.
If you use the stock airbox you need to check and clean your intake tract right now.


Looks normal outside, now look at the filter element:



Dirt passed right through, unfiltered. This will wear out your engine extremely fast.
Nearly all stock airboxes leak and pass dirt to a certain degree. No dirt or dust should ever get past your filter or end up in your carburetor.

I see newbies occasionally mention that they don't run an air filter, "because it won't run right with the filter on". Or "because it makes it faster". Do NOT run without an air filter, period! If your engine isn't running right, find the root problem. Also, running without a filter actually produces less power, it does NOT make you faster.

The Damage
  • Completely worn rings.
  • Destroyed intake stem seal.
  • Smoking like a freight train, with liquid oil passing through the combustion chamber.

The intake port. Note the dirt/grime going in.

The exhaust port. Horrible oil consumption issues. This engine is shot.

Solution: Get a High-Flow Foam UNI Filter.
Not a K&N Filter.
Not a no-name Chinese filter.
They are NOT meant for dirt and dusty environments.

Obviously I can't claim to be unbiased. However, I carry the UNI Filter specifically because it's the best at protecting our engines. If K&N or a Chinese filter were better, I'd be offering those instead. Every GY6 machine I own uses a properly oiled UNI filter.