Yeah, I recall most of the CRF450 owners that I know and ride with stick with the FMF brand on the exhaust system and silencer. Whereas the two stroke guys with CR250Rs go with Pro Circuit. I've got the Pro Circuit Platinum expansion chamber and a PC R304 silencer. Still have to repack the silencer once a year.
Here is an old video but with an older digital camera where I was testing out some jetting changes. Nothing spectacular. Hopefully this new Sony digital camera with video/sound works out OK.
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