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FMF Fatty for JR80

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OK, OK, so I know I'm not talking about a race bike here, or perhaps you wonder why I would invest $ for a performance pipe on a 80cc playbike, but I've gotta post this because I am impressed! My son's had this '01 JR80 for the summer. I've done what I could from the low $ standpoint to get a little more spit out of it - cleaned it up, opened up the airbox a little, and replaced the rear sprocket with one that has a few more teeth on it, and adjusted the carb right. All this helped - some. It still tended to bog at the low end.

So I decided to spring for an FMF fatty, cost me $165 with shipping. Yeah, I could've saved it for the 65 he'll probably get next summer, but I couldn't help it!! And I'm glad I did it because I learned firsthand how much difference an aftermarket pipe can make. This little 80cc playbike has been woken up! I installed it in about 20 minutes. I started it up and oh how sweet the sound, reminded me instantly of that crisp crackle of a true performance bike. As I warmed it up it was apparent that throttle response was zippier. I knew I had to have a test ride MYSELF so I got on. Undoubtedly snappier - not an RM kind of snappy but there's more zip than before, no question. Revs much quicker. Then the real test: there's a bit of an incline to one side of our property next to the woods that I've had to get a running start at with high RPMs before it would carry a full-sized adult like myself to the crest. I hit the incline with hardly any momentum, it just started to bog a little, so I opened the throttle, the revs PICKED UP, and when it hit midrange it started to pick up like I was on flat ground, I couldn't believe it!!

After my son talked me into getting off and letting him ride, that little JR zipped around with him on it NO problems, he zips through 4 gears rather quickly. He's used to having to get the RPMs up there to take off without bogging, now the front wheel comes off the ground! I had to re-teach him how to takeoff and now it's much easier for him.

If you can't tell, that Fatty made a big difference for a 9-year old boy today! And to be honest, it may just have re-inspired me to go back to a two-stroke!!

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