Yoshi -> FMF Full System

Just thought I would post up my initial impressions from moving from one exhaust to another.

Initial setup - Yosh Slip-on, Stock airbox and Filter (flapper mod), AIS removed. MAP - Dynojet3? (Leovince pipe and stock air filter setup).
Current setup - FMF Q4, FMF Powerbomb, K&N Filter, Airbox door off (flapper mod), AIS removed - MAP Rusty's Map.

First thing Ive noticed is the change in sound, especially of the intake howl. The intake damn near engulfs the sound of the Q4 though I think it sounds pretty cool. Q4 is noticeably quieter everywhere especially light throttle and even idle. Even the intake is quiet under light throttle allowing me to be quite stealthy compared to the initial setup. Ive definitely lost a bit of the hooligan sounding Braaaap the Yosh had but I feel it is a decent trade off for losing the loudness during commuting and longer highway stints.

Power-wise it feels like the mid-range and maybe up top gained a bit. It feels noticeably smoother throughout the rev range, so I wonder how much that changes my perception of things.

I'm debating doing the HF airbox mod and putting the door back on, has anyone gone from one to the other and noticed a difference power or sound wise?

Ill add more of a review as I ride if people are interested, made the change last night so things are pretty new.

I wish you had done more of a true back-to-back comparison.

Slip-on vs slip-on with no other changes. Apples to apples.


Just removing the airbox door and changing your programmer map would have made a huge difference with no other changes at all.

Did you chose to ditch the Yosh pipe because it was too loud?



Enjoy your new bling.

motokid wrote:

I wish you had done more of a true back-to-back comparison.

Slip-on vs slip-on with no other changes. Apples to apples.

Agreed, with the other changes he made too it's impossible to tell if the slip-on made any difference or if it was the other changes.

I definitely see what you guys are saying, but I was almost looking for a night and day difference to justify my purchase :). Except for the research value I think doing the changes one at a time would have been a rather time consuming and unfulfilling experience. It would have been nice to see how things looks dyno-wise as well but I blew all my money on the parts.