Exhaust for power

[Terry Hay]

Most people see an exhaust system as the logical place to extract a few more ponies from their favourite steed and rightly so. But in many cases the baby is thrown out with the bathwater. You see, the headers in most cases are extremely well designed and very power efficient. Any manufacurer is trying to not only make the best bike they can, but also the most profit. Better reviews mean better sales which in turn mean better bank balances. Hence the manufacturers will endeavour to extract the most effective performance outcome from their bikes and then choke them down to meet ADR's. This is usually done via the end cans. Most tuners will tell you that if you replace the exhaust pipe you will need to remap the fuelling. This is because the initial portion of the exhaust pipe is an extension of the exhaust port which will have an effect on how the motorcycle is tuned. In most cases however replacing the end cans alone will result in up to 90% of the overall power gain available with rarely a need to remap. When a motorcycle is designed the exhaust should be married to the combustion chamber design and the length and volume of the inlet tract to achieve overall efficiency. If a full system will provide an 8hp gain, chances are over 7 came from the end cans themselves. Think twice....spend once.
Terry Hay

[James]

I was talking to a guy at OP today that had fitted an ARATA full Ti system to his 08 blade. Apparently one of the best but at $3500 an expensive choice.

Really how much difference could there be between an Arata and what I have fitted to my blade (D&D twin slip ons) :confused1:
I thought it's only a couple of HP and most of the benefit I have already achieved by shedding 5kg from the stock pipe.....yes?

[KW4K4]

Great to have someone of your reputation contributing to the site Terry - good stuff and welcome aboard :ayyy:

[muzz]

the way i see it is chuck on a can and maybe a remap
i dunno, is a full system worth the amount of cash out lay ?
i can understand it if your trying to find every bit of hp outa your bike
but for street use i could not justifiy it.
id say a factory system is as good as it gets taking into account being mass produced and cost

[DR J]

I have to agree with Terry, why pay $3000 on a system when it only it seems to only work when you are on the noise down the straight stuff, turns require toque & drive. As for me I would recommend REECE plumbing their four inch downpipe (metal) really works for shmee.....

[Captain]

I agree too, if not from experience than from reading the reports from those that have done the mods.
I ride an 08 600RR, and in fact many owners reckon it's not even worth changing the rear (slip-on), as the reported power gain on this bike is only about 2HP at best. Hence I haven't .... but it's difficult, everyone keeps asking me 'when are you going to chnage your exhaust?'

[James]

I agree too, if not from experience than from reading the reports from those that have done the mods.
I ride an 08 600RR, and in fact many owners reckon it's not even worth changing the rear (slip-on), as the reported power gain on this bike is only about 2HP at best. Hence I haven't .... but it's difficult, everyone keeps asking me 'when are you going to chnage your exhaust?'
>

Yeh when are you going to change that exhaust

[wade193]

I agree too, if not from experience than from reading the reports from those that have done the mods.
I ride an 08 600RR, and in fact many owners reckon it's not even worth changing the rear (slip-on), as the reported power gain on this bike is only about 2HP at best. Hence I haven't .... but it's difficult, everyone keeps asking me 'when are you going to chnage your exhaust?'

Your forgetting about how much better it will sound :ayyy:

[Belinda]

I agree too, if not from experience than from reading the reports from those that have done the mods.
I ride an 08 600RR, and in fact many owners reckon it's not even worth changing the rear (slip-on), as the reported power gain on this bike is only about 2HP at best. Hence I haven't .... but it's difficult, everyone keeps asking me 'when are you going to chnage your exhaust?'

I have no idea what hp I gained from the slip on on my 08 cbr600rr, but it noticeably changed the power delivery. Felt like it had more torque and acclerates harder out of corners.

Its getting a PC and dyno tune in a week so will be interesting.

[Captain]

lol James :clap: cheeky bugger

Most people are somewhat surprised that in fact the 600RR doesn't sound too bad with the stock exhaust. Yes a slip-on will be nicer, but the oldies near my place are frightened already ...

EDIT: You might well be right Belinda, it's a theory that I haven't settled on yet. Some say it's pointless, others (like yourself) claim it's great. There's also a theory that it's the louder sound that's fooling you into thinking the bike pulls better. My blackbird certainly felt better with new exhausts too, yet the dyno said there's no difference :confused1:

[Marshy]

My Yoshi slip on on the gixxer 600 rocks, and sounds like a motogp bike! No need for anything more. IMHO.

BTW Cap, that's a profound footer you have there mate :ayyy:

[*Oggy*]

Slip ones are mainly bought for (1) looks... (2) noise (3) looks (4) looks (5) weight saving.

They are also an easy bit of bling to bolt on by the average biker (as in mechanical skill).

Not many would attempt to fit a full system with the terrof of removing fairings and de-plumbing the Radiators and oil coolers etc etc.

I'd get a full system (over say just a slip-on) for say a 5+ year old bike, but never for a newer one... (Like I'd really notice the difference......not)

[SLAC]

Most people see an exhaust system as the logical place to extract a few more ponies from their favourite steed and rightly so. But in many cases the baby is thrown out with the bathwater. You see, the headers in most cases are extremely well designed and very power efficient. Any manufacurer is trying to not only make the best bike they can, but also the most profit. Better reviews mean better sales which in turn mean better bank balances. Hence the manufacturers will endeavour to extract the most effective performance outcome from their bikes and then choke them down to meet ADR's. This is usually done via the end cans. Most tuners will tell you that if you replace the exhaust pipe you will need to remap the fuelling. This is because the initial portion of the exhaust pipe is an extension of the exhaust port which will have an effect on how the motorcycle is tuned. In most cases however replacing the end cans alone will result in up to 90% of the overall power gain available with rarely a need to remap. When a motorcycle is designed the exhaust should be married to the combustion chamber design and the length and volume of the inlet tract to achieve overall efficiency. If a full system will provide an 8hp gain, chances are over 7 came from the end cans themselves. Think twice....spend once.
Terry Hay

I think that slightly mirrors trev's thought if i recall right.. But from memory if you are after a bit more hp and a smoother easier riding bike, a PCIII tuned... I for one on the next bike will be just getting a can and PCIII tuned, already started saving the cash for that...

[saf]

Especially given the only performance limiting factor on my bike is me, that makes me feel better for just having my micron slip-on for years. Cheers for confirming my thoughts.

[Andrew B]

From what I have read over the years, the best modification you can make to a bike is lightweight wheels, whether they be alloy or carbon fibre, whatever. Similar price to a top of the line full system but far better results

[Big Lunt]

Depends on the age of the bike

I think now days the performance is extracted very well but older bikes especially carb machines do benefit from a full system.

I know for my R1 that the exhaust system shaved 4kg off the weight of the bike and also has made some extra HP.

[Pymm]

reducing your unsprung weight is a big handling improvement andrew, wheels can help alot in that regard!

[WET4URacing]

reducing your unsprung weight is a big handling improvement andrew, wheels can help alot in that regard!

untill u get to the straight.

[Jake]

untill u get to the straight.
Then what happens? :drivingsmiley:

[SIX36]

From what I have read over the years, the best modification you can make to a bike is lightweight wheels, whether they be alloy or carbon fibre, whatever. Similar price to a top of the line full system but far better results


I would say best mod would be suspension it is the be all and end all of handling, which makes you faster if u have more control...

A better set up bike with a stock pipe will be quicker than a non set up bike with a full system.

[WET4URacing]

hp bikes will go past you

[Jake]

Gotcha - thought there may have been some drawback to lightweight wheels.

[WET4URacing]

no just the cost.

[Birdman45]

Well for me what Terry said is right in some aspects and wrong in others. It depends on the bike to some extent, and the system you put on. In any case $3500 for an Arata Exhaust system is silly, I sold them all day long at about $2500 for that model. BUT again, some bikes gain plenty from the slip on and a bit more with good headers, others gain a little bit with the muffler and heaps with the full system, it's by no means a hard and fast rule.

Also, if we talk about GOOD full systems it is not a matter of 8h.p with a slip on and 10 with the full, and that 2 being made up of the last 2000rpm. Here's a graph of an 05 R1, stock vs Arata slip ons and then stock vs full system and mapping.

http://www.doinbikes.com.au/images/R1_2004_STOCK_VS_ARATA_SLIPONS.jpg

http://www.doinbikes.com.au/images/04R1_STOCK_VS_ARATA_MAPPED.jpg

slip ons made 5h.p, the system and mapping made 13h.p which is a bigger difference over the slip ons than the slip ons were over stock. The gains of the system and mapping were bigger from right down the start of the run too and made more power than the slip ons everywhere

As for mapping, that is a little like the suspension side/reason for doing it. Your bike could make exactly the same h.p after putting on a slip on, and then having that mapped, but it will be way nicer/easier to ride, be better on fuel, be easier to get on teh throttle and be able to do it harder from lower in the rpm, it'll drive harder off turns etc etc and so , you will ride it better/faster every time. Add to that, even a stock bike will benefit from mapping as they are far from ideal out of the box and each bike is different as well (ie: one will be out more than another of the same model bike straight from the factory)

One could also argue that if they spend so much on their bikes to make them so great to get more sales, you wouldn't need to modify the suspension at all, coz they'd be real good out of the box and the benefits would be negligible, but we know that is a bit silly too.. Hahaha

[Birdman45]

a K5 GSXR1000 that had a Yosh slip on, and then an Arata system and mapping. 10h.p. more and more power from 6.5K onwards. LOL yep, hardly worth it. LOL

http://www.doinbikes.com.au/images/GSXR1000_ARATASYST_VS_YOSH_SO.jpg

[Birdman45]

GSXR600 with a slip on, and then mapping. Would have given the bike more power than the pipe I'd imagine.

http://www.doinbikes.com.au/images/GSXR600_01.JPG

[Birdman45]

ZX10 stock vs slip on and mapping, and then stock vs Arata system mapped. do I really need to continue? hahaha

http://www.doinbikes.com.au/images/ZX10_STOCK_VS_ARATA_SLIPON_MAPPED.jpg

http://www.doinbikes.com.au/images/ZX10_STOCK_VS_ARATA_MAPPED_2.jpg

[SLAC]

So in essence, you need to know what bike perfoms better with a slip on.. And i think its fair to say that for $1000 -$1500 more than a slip on you should expect at least a 10hp gain... But overall you need to get a PCIII and map it to real get some real world gains

[WET4URacing]

oh yes please trev. and for your next trick lets talk about these hugely inflated HP figures people cum up with. 194.8 cum on

[Birdman45]

Hahaha, That does seem funny, but hey, they're just numbers in that context, don't mean jack.

Slac, mapping only gives your bike the power and delivery it should have already, but doesn't due to the fueling being out either on it's own, or due to the addition of pipes or systems etc. But as I just showed there, in the case of Arata or Sato anyway, that for around $1000 you'll get 3-5h.p on those bikes, and for double that you can get double if not more of the gains. Sounds fair to me. This isn't always the case, like I said, it varies for different bikes. For example the 929's and 954's........ same bike basically and any pipe n the 929 gave them 3-5 h.p, but on the 954, you could actually stay exactly the same or even lose h.p with a bolt on pipe. Yet, you could get 15-20h.p with the system. I have seen many posts on forums say that R6's you'll get 5-7h.p with a slip on and not much more with a system, but I know guys that recently put on two different slip ons on their R6 and gained 1h.p. (BTW I find that hard to believe and the way it was tested I have doubts on but anyway, another story) But a good full system will give them at least 10h.p.

In any case, my advice would be, if you want your bike running at it's best, and you are gonna add a pipe or system, then you need it fueling properly to get the most from both your bike, and your mods. I'd also suggest you do the same with your suspension. Anyone that had had there's done will tell you it is like chalk and cheese in the way your bike handles and allows you to ride once it's done and set up right.

[WET4URacing]

oh i got it , just looking at your tables . this is why these big HP bikes dont cum to have them on your lie detector. your dyno only goes to 175.:)

[Birdman45]

hahaha Nope, but it is lower than alot of dyno's I see, especially the non dynojet models that are supposedly "more accurate and lower than the DJ models" . haha

ZX12 stock vs Sato system mapped.
http://www.doinbikes.com.au/images/ZX12_Satosystem_power_rpm.JPG

[muzz]

fark 20 hp!

[Birdman45]

and more than that at redline. Good huh. You won't see that sorta stuff with Yoshi pipes and the like , that's for sure. hahaha

[muzz]

thats why satos cost the $ then i spose

[Kimbo]

Gee Terry. I found your thread to be very simplistic for an extremely complicated and dynamic issue.There are so many variables to the exhaust ,not taking in the the intake side as well. Really ., It's like saying Suzuki make the best bike. We all know the major manufacturers make great bikes but they arrive there by doing things differently , either subtly or by a different route. Then it's a matter of personal choice. Same with exhausts.

[Killer848]

So many bikes, so many different header designs and so many different can designs. Things can get so very complicated but with only tiny differences.

For me and my bike, i just put a set of arrows on and thats all i have done performance wise. The bike feels like a rocket ship now compared to before.
The stock cans were just so heavy and restrictive, resulting in higher temps and lost hp.
A set of headers for my bike won't give that same amount of gain on top of what the cans add but will definitely change the power delivery with less down bottom and more up top.

Now iv'e lost what i was thinking cause of happy gilmore! :lmao:

[Terry Hay]

Kimbo
I guess you didn't quite catch the entire concept of the statement. The manufacturers have to take everything into account. The exhaust is simply the tail end of a very complex equation. The exhaust should take into account the length and volume of the inlet tract as well as combustion chamber design. You could go further regarding pulse waves, header volumes, tuned lengths etc. My comment implies simply that the bulk of the power gain will come from the silencer rather than the headers. In 2000 we tried several different full exhausts on our GSXR600 and only one outperformed a Staintune race slip on....6hp. Moriwaki full system 7 hp. Yoshimura full system 4.5hp after tuning.
In 05 we ran an Arata end can in Superstock with great results. Adding headers in 06 yielded only small gains power wise although significant weight loss.
Full systems have their benefits when trying to eke out extreme performance and are a valid upgrade. I'm "simply" stating where the greatest gains are made.
Bang for your buck.
Terry

[Kimbo]

Terry I did understand . I just found it to be a very simple statement. As you now point out there are so many variables to do with exhaust. It's just like saying Ohlins is better than Showa or Penske or WP etc . There are so many variables to take into account and cost is one of course.

[Terry Hay]

Kimbo
I don't think you do understand.
I could talk forever on technical subjects which would be obvious to a limited number and would bore the hell out of most. This is a thread that could be easily accepted by the greatest number. The comments are solid, readily proven and sound economic advice. This is all it was meant to be. If you wish to extend on this.....post away.
Terry

[Kimbo]

Terry. Actually I do understand, and as I said it was a simplistic view. I agree , the technical side of the internal combustion engine fills vast books and a forum is really not the place to go into the thermo dynamics, portshape , valve timing, primary and secondary length ,collectors and all the different inlet side of things, as there are people
here who don't have a technical background. Some are happy with a standard bike and some have racebikes and everything in between, so of course your thread didn't and shouldn't go into great depth. All I am saying is it was simplistic and a generalisation. That is all and I was not have a shot at you.

[Killer848]

Ah yes thats what i was going to say thanks kimbo.

So in relation to the cans i put on my bike in simple terms, better exhaust cans = good bang for buck.

Cans only In money terms, $850 = more power and performance and my reaction :mod_smilie_rockwoot

Full system in money terms, 5K = About the same power gain with different power delivery, My reaction - Where's my extra ponies for that amount of money :confused1:

[Johnny]

What makes a good can ?.

They in most part are mostly straight through cans (AF's), so what makes one better than the other ?..

[Birdman45]

The taper of the lead pipe (if there is any) the size of the inlet and outlet of the muffler and the weight of it basically.

Killer848 you can get the Arata full system for your bike for about $3-3.5 and will make more power than the akra or termi system and you will not lose power down low. On top of that mapping the bike for the pipes you have on it will make it a different bike as well even if you think it is running ok now.

848 with stock vs arata system and mapping, no bottom end loss at all. But there is a dip at around 7K which is weird.........

http://www.ducati.ms/forums/attachment.php?attachmentid=41039&d=1229623356

[spamanglenn]

People need to look at the big picture of fitting a full system over slipons.what are the weight savings, that allow the bike to accelerate less weight.3kg less is equivalent to 1 ft/lb of torque extra,how has the centre of mass of the bike been altered? Remember an exhaust hangs low on the bike and fitting a lighter exhaust actually raises the centre of mass of the bike,is that favourable for your bike?What does the power curve look like at 10-50% throttle with the often bigger header diameters.100% throttle power runs prove that full systems make more power at 100% throttle but unless its a track only bike, a soft doughy part throttle will shit you to tears after spending 2k+ and unless your playing with ignition timing,air fuel can only do so much for part throttle torque with big headers.Stock headers and slipons for the street is a sensible option and full systems with fairly small primariies,big pipes need big revs or bigger cubes to work properlylight wheels and good suspension can be enjoyed at ALL road speeds so you enjoy the benefits of your spend even just going up the shop for milk.:ayyy: