It's really fun to play with engine improvements, and as Denno written to you, your improvement to be noticeable has to come with re-tuning the map in the ECM. I have been trying for a while to figure out how to get free maps for our CBR250R, and if there is a cheap (amateur) tool with which I can install the new map to our ECM. If you will know the subject, before me, then you are welcome to sharing us about it.I removed the rubber elbow that goes into the airbox and dremeled out about a 4 square inch hole on the bottom piece of plastic between the battery and airbox. Butt dyno says it made a non-negligable difference. As you know, power falls flat on its face after 8k rpm and this seemed to help extend the torque curve a bit. Anyone have other mods to help it breathe better up top?
The guy in the attached video (Yamaha MT-7) "removed the rubber elbow that goes into the airbox":