Sports Exhaust Behaviour

Discussion in 'Maintenance' started by Movistar, Sep 28, 2011.

  1. Movistar

    Movistar Active Member

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    Hello !

    Got an urban exhaust fitted to the blade. In 3rd and occasionally 2nd when I slow down at around 3-5k revs I sometimes get a nice rumble from the exhaust which makes the bike accelerate very slightly then goes back to normal. Is this normal - I actually quite like it because it sounds pretty cool and I don't mind non smooth bikes particularly as long as it isn't running like a dog.

    Cheers
    B
     
  2. dan.1moore1

    dan.1moore1 Senior Member

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    Is there a power commander on the bike? If not its probably just due to a change in the fuelling from the free flowing exhaust . shouldnt be to bad on your bike as the cat is in the headers
     
  3. Movistar

    Movistar Active Member

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    no PC as far as I know.

    It is quite funny as you occasionally get an extra deep rumble or two outside of the normal sound, I think it sounds mint.
     
  4. dan.1moore1

    dan.1moore1 Senior Member

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    Yeah i love it when mine pops when decelerating .. As long as its all running good enjoy the noise fella
     
  5. JM1

    JM1 Active Member

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    Not sure if this is what you're talking about, but the 08 onwards bikes have a system which injects some fuel around those revs when closing the throttle and slowing down (Idle Air Control Valve I think it's called).
    N.B. This is completely separate from popping/backfiring due to PAIR valve/exhaust leaks/fuel mapping. AFAIK, if your bike isn't an 08 onwards, it should not be "accellerating" itself and you should get an FI controller (eg, Power Commender) to adjust the fuel map.
     
    #5 JM1, Sep 28, 2011
    Last edited: Sep 28, 2011
  6. Movistar

    Movistar Active Member

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    its not so much accelerating but does a slight jump forward when the exhaust pops as dan put it - it doesnt bother me and I like it. I assume its not harming the bike either
     
  7. JonnyAnnett

    JonnyAnnett Active Member

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    Sounds like fueling/mapping issue. A Power Commander and a bit of mapping wouldn't go a miss, if you wanted to smooth it out and get the most from it.
     
  8. Remal

    Remal It's ME
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    As above, I get stunning noise with my r77 on track or when revving hard. But no going/jumping forward
     
  9. Jamz

    Jamz Active Member

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    Got a nice deep throaty sound from the BOS ive got but dont get that pop when decelerating... Oh man i miss my R1 with the twin Race Akcro's.. Now that was some seri-ass sound :)
     
  10. slowr1der

    slowr1der Active Member

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    Once you get your R77 on there mate you will love it
     
  11. Jamz

    Jamz Active Member

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    Yea..just need the dosh and right price to come up
     

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