of course it is noticable, or nobody would do it. LOL But as to exactly how much hp you're gonna get, well to be honest, it's not what mapping is all about. The gains you get are what your bike should make anyway, but doesn't coz the fueling is crap. You will notice a smoother ride, you'll feel stronger pull from lower in the rpm, without the lag or stumbling you may have now (even ifyou don't feel like your bike is "so so", you'll think it was after you feel it mapped) it'll be better on fuel, it'll have a smoother on/off throttle. There are far more advantages to mapping than just adding h.p. Do it and see.