2013 RMZ 450 FMF F4.1 Exhaust/Arrestor by Steve O OEM-CYCLE consultant
I recently purchased the FMF F4.1 exhaust/spark arrestor from OEM-Cycle which was tested in the hills of Central California. So what do you get when you receive your shipment? An Exhaust, mid-pipe, spark arrestor insert, insert snap ring, replacement bolt for exhaust mount, exhaust plug and enough stickers to cover you and your friends bikes and possibly your neighbors car. At first inspection the welds look good and the mid pipes fit is snug with a nice tight tolerance. When compared to the stock exhaust the overall size, length and weight are diminutive in comparison with a total weight savings of approximately 2.9 lbs. I have always said if I can make a bowel movement as big as the weight saved on a high dollar part I might be better off saving my money. With that said 2.9 lbs. is substantial.
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The directions are straight forward and the removal and replacement of the exhaust will take you all of 15 minutes. I used a high temp silicone sealant at all connection points to prevent any exhaust leaks. The fit was perfect with absolutely no hammer antics or destruction of garage property. Thanks FMF!
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So how does it perform? Well, as with any exhaust, you plug it up with a spark arrestor and the performance of the bike suffers. The only notable difference was sound (muffled) and that snappy response from a free flowing exhaust. I don't know how much horsepower is lost if any so my opinion is only by the seat of my pants. All in all it was exactly what I expected. Aside from a perfect fit and finish I really like the fact that I can remove the spark arrestor in a matter of minutes for race track use. I will let you know if any performance gains are found when I go back to Zaca Station and unplug the beast.
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Steve O
