My quad is 400 ex 2005. Im thinking put in it, in the next days a HMF pipe, a good foam filter, and hotcam stage 1. No more modifications in the future for the motor of my quad. I ride mainly in rough trails in the woods or mountains. I dont need more velocity, only need great power in low an medium range. For my tipe of rides and the few modifications on the motor,... I must buy the HMF SPORT SERIES SLIP ON(210 DOLLARS) OR THE HMF FULL SYSTEM(430 DOLLARS). ?? What do you think? The inversion in the full system is justifiable? Thanks in advance for your response.

 

I may be wrong, but I dont really see how the pipe could make that much of a difference. I would think the flow is mostly affected in the slip on..Thats alot of difference in the price for the full pipe. Use that money somewhere else.