Ive never heard of this until recently. But its maintenance and good value for money for HP/KW.
There is packing inside of the exhaust that gets old and needs to be replaced.
You can buy it from Ebay or a motorcycle store for around $20.00 herw in Australia.
I got the normal one cause of an exhaust upgrade i will be doing. But if you like standard exhaust get the FMF packing cause it aperently increases HP?.


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Remove your exhaust and make sure its cold.
Drill rivets out.

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Make sute you take note on the way the exhaust comes apart.

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