Originally posted by Steve Burke:
5 horse, you'll notice the difference. You're going to gain low end torque as well, and I'm not familiar with M4, but my Hindle was so much lighter than the stock exhaust. The only problems with full exhausts for bikes, you might gain as much as 10 hp (to the wheel) but you might even end up losing power, I've met a few guys who dynoed afterwards and were dead even or lost 1-2 whp. I think the sound alone is worth every penny, so a slip on might be a consideration....ever pass a bunch of stopped cars behind someone turning left and some joker pulls out in front of you because he didn't see/hear you? With the new can or better yet full race exhaust, pull in that clutch for a sec and jab the throttle. You get noticed and that's a great thing on a bike, much safer.
The 600cc supersports all seem to lose some torque from a full exhaust system until around 5000rpm, then gain a few ft-lbs throughout the band from there in.
The SV650 gains about 4 to 5 ft-lbs all the way up to around 5500rpm, then that gain comes down to 1 to 2 ft-lbs till redline... thats only on a new can and midpipe. I do believe with a full system there's less of a gain (maybe even a loss) in bottom end torque, but lots more gain in midrange and top end.
