i bought the FMF put it on i dont really see any change if anything i seem to lost some power... with out the FMF i could in 2 gear just roll into a wheelie and keep it up till i brought it down now i really seem to have to work to get it up...anyone esle have this pipe and can tell me what they think any info would be great

 

Don't have the pipe but what is the sound like? Is it anything close to stock, or is it loud like any other aftermarket 4-stroke exhaust system?

 

Yes it is loud alot louder then the stock.... but as for more powerfull i dont see it or im just not sure to it range of power

 

Did you fatten up the fuel mixture any? From everything I've read, you need to rejet a size or so bigger when you put on an aftermarket pipe, or else you'll be too lean, which could cause the loss of power? I dunno, mine's still stock, so I only know what I've read.

 

FMF makes good 2 stroke pipes but for 4 strokes in my opinion Supertrapp makes better ones.

 

I have just put the powercore IV squared on my 400ex and it is a day and night diffrence the power is all the wat thought the powerband,its a little louder than stock at idle but it realy has a deep tone to it it sounds great I would say that its the best mod I have put on my bike. What your jetting ????

 

I still have the stock jetting i need to change it soon......the dealar i bought the pipe from said i didnt need to change the jet after talking to alot of people i think he full of it . i know now i need to just dont know what jet to goto for the state i live in..ohio

 

change your jetting, and the power increase will become noticeable...anytime you increase airflow into your intake system or out your exhaust, you will have to rejet.

 

Call or e-mail FMF about the jetting that's what I did, I live in Florida and FMF told me to go up two sizes on the main for just the pipe,and if your are running a vented air box lid to go one more size.You can jets the jets from your dealer and trust me once you get it rejetted you wont be disappointed

 

I went up three sizes on mine (158) and it's a huge difference. I also went up to a 40 pilot jet since mine wouldn't idle when you first cranked it. Now she purrs like a Tiger cub.