Duncan Fat Boy 4

[Master400ex]

I was looking through an issue of Atv Sport today and I saw an advertisement for the Ducan Fat Boy 4 supposivel y it gives 20 percent increase over stock. I was going to the get the Sparks X4 but now im not sure?? Im looking for mostly bottme to mid range power. What would be better and why?? Thanks Master

[mopar 400]

I actully just had my old Duncan Racing Double Barrel exhaust replaced with the new Fat Boy 4. The construction of this pipe is awsome. I have yet to ride it, just got it yesterday, but I will let you know how it compares to the sparks. I have ridden both the X4 and X6 as well as procircuit T4, WB eSeries, and the FMF powerbomb with the FMF mufflers.

[holeshot19]

i have one too.but i got one because we have a dealer hookup and when i looked at all the pipes there going to be not that much different all you can do is get what you want. and besides you need engine mods to really make any pipe work.

[EXflattracker]

I run one of these pipes and I love it. I like the sound of it most of all. It seems like mine adds more mid to top then bottom end grunt though. I would suggest this. Get it, you'll have no regrets.