Hmm, was wondering what kind of fuel you are using because never heard of 13% nito fuel?? Check the oil content, it must say that it contains at least 18% oil or your engine will not be protected. Since you are starting out and want to use this engine foe training, just leave the baffle in. The engine will be easier to adjust for reliable running and it will run quieter. Btw, a fuel with 10% nitro content is all you really need for most applications. Just for info what prop are you using?