What year is this bike? You must be very careful about how you modify any Whizzer motor between 1999 and late 2004. The WC1 engine has a bad habit of loosing the valve seats when modified. The WC1 does not like the extra heat generated by modifications. The NE5 on the other hand does well when modified. (2005 on up) Now that we have that straight.
When you say baffle do you mean the exhaust baffle or the restrictor plate behind the carb? If your talking about the restrictor, put it back in. You can open it up to match the intake but it is needed to help keep the heat down in the carb. This is very important. Another thing you can do is advance the cam one tooth. Tilt the bike over to about 45 degrees and take the side plate off. It may be easier just to drain the oil but tilting the bike keeps you from having to do that. Rotate the crank until the dots line up on the crank and the cam. Move the cam one tooth counter clockwise and reassemble. Sometimes the cam comes out with the cover when it is removed. It is very simple to put back together just make sure the lifters stay in place. Good luck and let us know how you make out.
Jim