Me and my brother when out riding the other day. when we were coming down to stop sigh at the bottom of the hill, I rev match down shifted from third to second gear going around 35 to 40 mph. I hit the down shift flawlessly and began to engine break all the way down to the stop sign. during this time my engine seam to give off a high pitch hum from the high RPM ( i do not have tac on the bike so i don't know how high the rev were). apparently the hum was even loader behind me was my brother informed me after the ride. he said i did down shift at too high of a speed, and that i could damage the engine by doing that. what is your opinion?