Exhaust rumours?

[naphazoline]

hey there folks.
i was just wondering if you would tell me if it's true, that adding a sports muffler can add a 10% increase in power? (this was what someone recently told me).
or should that be a complete exhaust system?(the latter sounds more realistic to me
cheers

[Ixion]

Yeah, a power muffler will easy add 10%. But a set of racer decals will add , easy, 20%. And painting it red is good for 15%.

[Squiggles]

Full systems > bolt on's as far as any performance gain goes

[The Stranger:Me]

No doubt there is an exception somewhere, but mostly they are yanking your chain.

By way of example the Yoshi slip on can on my Fazer yeilded 5hp (132hp-137hp) when remapped. Yoshi headers are said to yield another 3 peak, but 8 in the mid range.

[CB ARGH]

Yeah, a power muffler will easy add 10%. But a set of racer decals will add , easy, 20%. And painting it red is good for 15%.

Well put.

I thought of getting a hot exhaust system for my gay old Pulsar, but decided it'd make me use more gas (to hear it, of course).

Not that the above has anything to do with bikes, that is.

10%? Highly unlikely. Not impossible, however.

[98tls]

Add what you like but to get any worthwhile gains you have to attend to the other end as well,manufacturers of go fast bits make many claims,basically put enlarge your arsehole all you like but unless you rip your head off and open up the intake its not going to acheive anything remarkable when "doing the shit".

[AllanB]

Back in the old days (late 70's early 80's) a pipe and a carb rejet could realistically gain a 10% increase. But remember that meant your 60 hp bike hit 66 hp and it was noticeable. Thus the old tale of a significant increase.

On a modern, water cooled injected bike you'll be lucky to gain a hp or two increase with just a can replacement so now your 160 hp bike might go to 162. Now that's going to rip your arms off!

You will however save a few kgs of weight off the bike (always good), gain a deeper pipe note and if you are lucky it may well run a bit smoother and rev slightly freer.

Oh and look cool as well.

The biggest way to gain HP on a modern bike is to actually open the throttle to the stop - on anything 600cc and up in most normal riding you are using very little throttle.

[avgas]

yep 10% is possible, but not to peak power, at 50% peak power.
By allowing the bike to breath better this usually increases both low and midrange torque......but does nothing to peak.
However all that said i would be supprised if just a pipe gave you more than 5%......more likely 1-3%.
Headers should give you more mid.....mabey a bit more peak.
Full system (including intakes) gives you over all increase.
Mapping is fantastic at removing modern bikes "restrictions" especially on vehicles bound to europe.
The funniest part is if you make the pipe to the wrong design, or no pipe......you loose hp

[gunrunner]

Yeah, a power muffler will easy add 10%. But a set of racer decals will add , easy, 20%. And painting it red is good for 15%.

And painting it red with flashing LEDS down the side - PRICELESS

[R6_kid:Me]

Adding and aftermarket exhaust to my old R6 LOST you 4hp, re-jetting it right got those 4hp back and then putting in an air filter an re-jetting it again if need be added a little. That's 4hp/100hp so 4% ish.

What it does do is remove a generally ugly and heavy stock exhuast pipe, and replace it with something that allows the bike to make the noise it wants to, and look nicer (generally) in the process.

[naphazoline]

Yeah, a power muffler will easy add 10%. But a set of racer decals will add , easy, 20%. And painting it red is good for 15%.

sounds to me,like you got a bigger gain than that, by ramming one up your arse.

[klyong82]

Add a muffler, hiflow air filter and a power commander and been dyno could give you the extra 10%

[pritch]

Add a muffler, hiflow air filter and a power commander and been dyno could give you the extra 10%

That's fair.

Ignore what the ads say. Some of the slip-on systems around will actually lose you power. At best the gain is minimal anyway.

If you want to do it for aesthetic reasons that's OK, but don't expect to gain anything except maybe more noise... And maybe the odd argument at the testing station.

A lot of money for not very much at all really.

[NighthawkNZ:Me]

Yeah, a power muffler will easy add 10%. But a set of racer decals will add , easy, 20%. And painting it red is good for 15%.

Don't forget looking the part in full racing leathers also good for an extra 10%...

On a serious note as 98tls said... you got to do the other end as well if you want any serious change

[naphazoline]

i really don't care for the power gains. infact i could do without them.i got more then enuff power to lose my license,but it would be nice to have a bit more noise,as it's just got the factory exhaust minus that butterfly valve that makes them sound like an electric engine.
might look at something next year.