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The OEM foam secondary filter can deteriorate rather quickly. Once that happens, it can allow enough dirt into the engine to do significant damage. Replace your filter now with a high-quality foam filter from industry leader Twin Air.
This filter needs to be oiled like any air filter to work properly.
Only for bikes with the stock BST40 carburetor!
Twin Air's high quality materials and superior construction deliver unbeatable performance and protection. The hands-down choice of more World and National Champions than all other filters combined.
Twin Air's fused layers of open-pore foam and fine inner foam trap even the smallest particles-without restricting airflow.
