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Aftermarket exhausts

Discussion in 'Riding Gear and Bike Accessories/Parts' started by gunnin' it, Jan 5, 2006.

  1. hi, i see and read about loads of people who fit aftermarket exhausts, but i am left wondering due to the different oponions out there. Do they REALLY increase performance??

    Ive heard that in some cases they can cause your bike to lose HP :shock: ...is this true?? and wats the go with this talk of "rejetting" and new chips ie "power commanders" etc that often/sometimes goes with the fitting of a new exhaust system or can??

    so whats the verdict....do they actually improve performance or do people buy them just cause they look "race" and sound horny?

  2. People buy them for the looks and sound, if the truth be told. There are certain exceptions - for example the Bandit 1200 has such a restrictive stock exhaust system that fitting the appropriate aftermarket item actually takes the bike from 100ps to around 120ps - but in most cases the pipe alone might 'liberate' 3 or 4 horsepower on a larger bike, which would hardly represent value for money.

    The small gains are often because stock bikes are set up to meet emissions regulations which compromise maximum power.

    The exhaust performance and back-pressure are key elements that are taken into consideration when setting up the fuelling of the bike, whether it's by carb jetting or fuel injection mapping - so putting a non-stock exhaust on the bike that changes the back-pressure will mean that the fuelling is no longer set up correctly, allowing the bike to run lean or rich, compromising fuel efficiency and in some cases resulting in decreased performance.

    On carbed bikes you can change the jets/needles to more closely fit the new system. If the bike is fuel injected, the injection mapping needs to be changed. Suzukis have an inbuilt system that lets you adjust the high/mid/low rev fuelling by, i think, 5% either way from stock - crude but reasonably effective. For any other bike I believe you need to fit an aftermarket injection map management system like a Power Commander (at considerable expense) which you can use to tune your bike very accurately to suit the new system all the way through the rev range and optimise your power, delivery characteristics and/or economy.

    Not that I understand this shit, I just did some reading when I noticed the Hornet was less efficient than it oughtta be and suspected it might be the staintune pipes to blame. It runs rich, a condition which could be addressed using a power commander if I wanted to throw $500 at it.

    The main thing though is that it can change the feel of your bike - the new sound and slightly different engine characteristics can make for a more exciting ride - and in most cases that's the clincher.
  3. On most larger capacity (4 Stroke) bikes a well designed exhaust will increase performance, noticeably. Most would benefit in the way of smoother running and maybe a smidge more power if you re-jetted or fit a Power Commander. Re-Jetting is done to adjust the carbies so that the bike runs smooth and not lean/rich with the now increased airflow. The power commander does the same thing basically but is for fuel injected bikes (change fuel maps/timing etc).

    I guess you could LOSE power if you fitted an exhaust that was not designed for your bike, ie it had WAY too much airflow or too little airflow. However with a proper designed can that is unlikely.

    On a last note i think most people fit them just because they look race and sound horny. The extra ponies are usually just a good reason to validate spending money on your bike to make it sounds better :p
  4. I ain't dyno'd it, but the termi race exhausts I've whacked on give me an extremely noticeable power difference on the monster.
  5. Was going to start a topic but since this is here may as well ask. Anyone used Megacycle exhausts? I called up today to ask about one for my CBR250R. Poor phone service aside, and high price tag ($425 for can and $150 to fit to the singleR), whats the go? How much louder are they? Do they sound 'nice'? Any thoughts?

  6. You must have spoken to ken :) .. I have one fitted on the 12 and am very happy with it. Yes ken is a little hard to get along with at first, but in the end he was very helpfull. I would highly recommend his products. can you fit it yourself?? And as for the price, i wouldnt think that was too much, but i am not sure what other pipes are worth.
  7. sounds like a good price to me - the staintune for the VTR cost me $600 (and that was a good deal).
  8. There you go !! I thought he would be cheaper. I know i saved a few bucks buying the megacycle.
  9. Recently fitted one to my GSX 750F , very happy with the results. Sounds better , looks the part and cost wise, damn good.
  10. The pipe I added to the Triple sounds HORN!! The flash memory change to the fuel injection takes about ten minutes and it's ready to go with better throttle response, about 5 horses in the mid-range (just where I like it) and, of course, a noise like a stuck banshee!!!

    PS Peter Stevens, Ringwood didn't charge me for the fuel injection map
  11. Blue12, i could fit it myself and would be more inclined to buy it that way (i work part time as a TIG welder), however, im not sure whats involved in the installation (as the can is actually made for RR and requires slight modding to suit the single R).

  12. megacycle are the cheapest cans for a reason : :] .... you kids and your loud cans on your mosquitos ... theyre already embarrassing enough ::])
  13. Well, one day when im big and tuff and not a kid anymore ill buy a big tuff GSXR1300, then i can call you a kid. Hehe :)

    To be honest i just like the idea of a loud exhaust for safety reasons too (people can hear you coming at least, 250's are pretty quiet otherwise). And on top of that i've heard a few aftermarket cans and the sound grew on me. Sure, it is only a 250, but i may as well enjoy my time on it. Only 12 months to go!

  14. mate, not sure where you are located but if you are ever heading to a coffe night and you can have listen to just how loud they actually are. I have megacycles on my zzr250 kwaka, and you can ask quite a few members that have heard or been riding with me and the comments are fark thats loud. I personally also think that being louder is better for safety reasons like lanefiltering that and they do sound great :wink:
  15. Hey mate, im in SE suburbs, Hallam, not far from dandy, will do, question now is, where does one find out about a 'coffee night'? Rideout section?

  16. Just remember with a loud exhaust that other people have to live with it to.....
  17. If it's too loud, your too OLD!! :p :LOL:

    yeah check out the ride and get together days, then there is both a friday night and monday night coffee
  18. On my CBR i had a 7HP increase in power when adding the pipe and air filter...
    More importantly, I had more power in the middle of the rev range..

    Yes, the bike has to be re-jetted...
    It sounds really flash, but basically there are some injector needles (they look like big hypodermic needles) that are in your carborators... and they need to be lifted up or dropped down to adjust the fuel for the increase in air going through the engine...
    (As you know, combustion = Spark + Fuel + Air )

    Thats on a carbarated bike...

    On a EFI bike... in a lot of cases EFI will make up the slack without any investment... But if there is a big difference between the standard exhaust and the one you are replacing it with the computer has to be told how much fuel now needs to be injected into the cylinders... that process is called "remapping".... basically, reprogramming the computer... In some cases that cannot be done easily, so you have to get an after market computer which sits between your real computer and the engine and alters the actual readings to suit your bike... that is what a power commander does...

    I've simplified it a bit, but that is basically what I understand... (please someone correct me if I made any errors).

    To answer your question...

    Most people add the after market exhaust for looks and for sound... Very few people add them for performance... and without the proper tuning it can lead to less power..

    However, that said.... on an older CBR (F4i and earlier) the origional factory exhaust was HUGE and really heavy.... so it was well worth replacing...
  19. Pardon? I can't hear you :LOL: :p
  20. As most have said, the benefits of an aftermarket exhaust are in a very mild power gain with appropriate setup, and noise.

    Mostly noise. :)

    If you're after power, it is the obvious first step, but after adding in the cost of rejetting/kit/PC and a new air filter (usually) it's a fairly expensive way to add maybe 5-10% performance. If you're looking to improve the sound anyway, or the looks, then a new pipe is the way to go! Obviously all the brands sound different on different bikes, so I'd hunt around for people with the same bike as your own with a custom pipe, and see if you like it.

    All said, I'm sticking with the stock one on my ZX9R for now. It's big, but looks alright. I don't need any more power (it's already too much :p), and I certainly don't need it any louder.