A month ago my boy dropped two teeth on the front sprocket of his 2001 CBR 929RR. In a drag race he would pull away from me pretty darn hard after he did this mod. He heard that by taking the H-tev valve out along with the funnels inside the intake box that he would have some power gain. He has now completed all of these things. We had a little grudge match today and I had pulled about 7 or 8 bike lengths on him by about 150 mph. Dropping two teeth on his front sprocket also made his top end go way down I got him up there too. Bottom line do not take out or mess with the H-tev valve.

 

Honda puts those things there for a reason...it's not wise to second-guess them unless your goals for the motor are totally different (ie. Formula Extreme racing or something). My VFR's motor is staying bone stock...I'll get my tinkering fix with my 2-strokes

 

2 down up front is a bit extreme. Personally for a similar gearing, I would go down one in front and either 2 or 3 up in back. The 929s run 16 up front right? Seems 14 would start making an appreciable difference on the chain wear