new exhaust for more HP

how much power increase BHP can i expect from a new exhaust pipe??

[northwind]

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 can offer a full M4 full exhaust system with stg2 jet/air kit for the 99-02 models or the induction kit for the 03 onwards models, supplied and fitted with dyno print outs showing before and after power gains for £750.00 for the alloy can option or £850.00 for the carbon or titanium option.
jh
www.jhsracing.co.uk

[northwind]

's a good price. How much power would you expect to gain with the breathing mods alone, typically?

we would hope to see a 10-12% increase in power from the machine as supplied stock to us. Dyno graphs will be given to back up any work we carry out.
jh
www.jhsracing.co.uk

[northwind]

So 7-9 bhp... Or £100 per horsepower if you prefer This is what i was talking about when I spoke about relatively low returns for the cost. If you take, for example, a carbed model SV and do the K3 intake/cammed model intake mod, for example, you can expect much of the power at a fraction of the cost.

(JHS does a better cam option, btw, but I'm cheap £130 does the K3 swap, his Stage 2s are better but they're not twice as good, and cost more than twice as much. But that's a personal call. I've not tried his so I can't really offer an opinion)

I'm definately not against doing breathing mods, FWIW, I've done it myself and i wouldn't automatically advise against it, but you do have to be realistic about what you're going to get... The JHS jet kit's really good (Race RS filter, best direct replacement filter there is for the carbed SV, for example) and M4 have a superior rep, so that gives you a good idea of what's the best you can expect. If you do it with different parts, cheaper systems, K&N filters, you'll get different results, and most shops will charge you more for the setup than JHS as they won't know SVs to the same extent.

And once you're getting into spending £100 per horse for a street bike, you've got to take a long look at it and decide if it wouldn't be money better spent on a different bike- or on handling improvements, since £100 spent on suspension and brakes on an SV is IMO always going to be better than £100 spent on power. I've spent roughly the same on handling as i have on power, I know which one makes the bigger difference day to day or on a track.