Two Brothers juice box

[Turtlechaser]

I have a Yoshimura exhaust. My Sh150i used to pop and backfire a little when decelerating even when I still had the stock exhaust on it. What's happening is that it's running lean at the low speed and results in incomplete combustion which dumps into the exhausts and ignites from the heat in the exhaust. After I added the Yoshimura exhaust, the problem became far more pronounced. Overall it seemed to run fine, but the backfiring is annoying, and certainly isn't good for the engine or the exhaust. I recently added a Dynojet PCFC (Power Commander Fuel Controller) which remapps the fuel. My scooter runs better with it, and no more popping and backfiring! I purchased it direct from Dynojet for $249 and I'm happy with it's performance. I even think the scooter sounds better with it, because it's running a better fuel ratio than without it. I'm sure my gas mileage has decreased slightly, but I'm less concerned with that than I am with the the way the scooter runs. The PCFC is worth checking out. It also allows you to alter the included map without even connecting a computer. There are 3 analog potentiometers on it which allow you to adjust the low, middle and high range fuel air mixture. With all of these set to no adjustment, mine was better, but I slightly richen end the low speed adjustment and it's even better now. It does also allow you to connect a computer and remap that way if you choose to.