What bike? What other mods? The short answer's "not very much", even if you get a godo filter and a perfect remap. A few horsepower. You should get other benefits though, quicker engine response... I got a much longer peak with mine, whcih is nice- pulls to the redline instead of dropping off.
But it's bloody expensive for what you get- a new qulity system, filter and dyno time will put you around the £1000 mark. Then again, a used quality system and filter, a dynojet kit and loose jets (from Ebay) and a lot of trial and error means I've got a pretty nice setup for about £300. (carbed model obviously)
Also, if you do more tuning, a standard system will hold you back. Still, I'd say if your goal is a bit of extra power, cams make more sense- they're far cheaper, and if you do the various mods with stock parts, need no setup time.
__________________
"We are the angry mob,
we read the papers every day
We like what we like, we hate what we hate
But we're oh so easily swayed"
|