[smo0oth1]

Ready to purchase exhaust.... Which one???

Ok I have a power commander and velocity filter on the way. I cannot decide on which exhaust to purchase. I have looked at them all but do not have enough atv experience to know any pro's and con's of each company. I am leaning towards the HMF since this is where i got the controller from.. Well then on top of that I do not know which full HMF system I should get? I will be using the bike for general track and trail riding. Any help would be appreciated from experienced members.

 

[smo0oth1]

Bahh its a bit slow on here.... Well I purchased the FMF super bomb header cause I'm just itchin for more power. Still undecided about the muffler, are they all pretty much the same? Can I get one of the quiter ones and not lose sufficient power from a louder one?

 

[xx-rated]

Are other pipes compatible with the FMF Powerbomb? I wouldn't think they would be. I'm getting a HMF Ballance pipe with the Dobeck commander and a Velocity air filter. Ordering it all right after Thanksgiving.

 

[smo0oth1]

Yea they should be, it says they will bolt up to a stock muffler if needed. I talked with someone earlier and purchased the FMF Q4 Silencer. He told me of one of there trail ride friends having one of the FMF racing pipes and no can stand to ride near him its so loud. How much of a difference should I notice with the Header, Exhaust, Commander and Velocity Filter?

 

[xx-rated]

I would guess 3-5hp but it will feel and sound like much more!!

Isn't that what counts??

 

[smo0oth1]

Lol, yea I suppose but dam.... 3-5 HP cost 900.00$ !!!

 

[scuzz]

Lol, yea I suppose but dam.... 3-5 HP cost 900.00$ !!!

I like my exhaust loud. My HMF that was on my 400EX was awesome!

 

[xx-rated]

Well if you pull 5hp that's about a 10% increase over stock. Does that sound better?

 

[red4life]

I think 5hp is being very modest, most modern 4-stroke quads gain about 7-10hp over stock from an aftermarket pipe. Dont see why the XX would be any different.

I would have went with HMF, I dont think its a good idea to mix and match silencers and headpipes, and Im thinking it probably wont fit unless you got a FMF silencer too. It may work with the stock silencer but that doesnt mean it will fit other aftermarket silencers.

 

[xx-rated]

Really? 10hp? Man that sounds like a lot. But I'm certainly not an expert. Dyno's on the HMF and the 2Bros both show a 3-5hp gain with a slip on, controller and no airbox lid. Looks like 5 is the magic number in the 3500-4500 rpm range, then it drops a bit. I would think that with a full system you would pull more, but not double it. Then again, I don't really know. I'm going with the slip-on, filter and efi controller combo. I'm sure that I'll be happy with it.

 

[scuzz]

Who sells the slip-on and controller combo? FMF?

 

[xx-rated]

HMF, 2Bros, FMF. Probably anyone that sells their own pipe sells a EFI controller to go with it.

 

[trailin'me]

you aren't lying ..the 4.1 exhaust is LOUD haha ... but it rocks. i have one ..and no complaints here. shit ..with 110 fuel at night time my friends say all they can see is my rear light and blue flames coming out the back haha ... oh not to mention they can hear me miles and miles away.

 

[smo0oth1]

Well I ended up going with the FMF Q4. Here is my post on the other site...

Monday I finally received all my parts. FMF Q4 Exhaust, FMF PowerBomb Header, Velocity Air intake and HMF Optimizer. The install for all the parts was very simple and straight forward. I seen a few post of the Velocity being hard to install but it was very simple and went right on. The Optimizer didn't take much either you can install it with only removing the seat and plastic shielding. The exhaust only required removal of the small body plastic near were the header and and mid pipe connect. I was surprised to find out you only use RTV sealant when installing the header and muffler together, There is no need for a clamp.
Well on to the before and after results..... HAHA! Its been raining ever since

. I tried to go ride across the street in a a field but you cant even roll the throttle in fourth without breaking loose! Keep in mind this is in a wet field though. Hopefully it'll dry soon to catch traction and feel how much harder it'll pull.
Lastly.... After only ten or fifteen minutes of ride time the dam canister blew a gasket at the rear of it. I had to pull it off and send it back for a exchange. Although I loved the sound of the exhaust I asked them to send me the PowerCore 4 instead if they could. I think the Q4 may have had to much back pressure resulting in the blown gasket.

 

[smo0oth1]

Here is a few pics

And the leak after 1 few min of riding, Its seems to be a factory flaw. Was leaking where the two lines run under the shell