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another exaust/pipe/de-baffle question.. Corrrrd!!...i hear

Discussion in 'Modifications and Projects' at netrider.net.au started by Nel, Oct 16, 2007.

  1. purchased my first cruiser recently.
    Honda VT750C '03.
    it is of standard issue.
    peaceful quiet.
    then read on these forums about 'sound is safer'
    read also about 1/2 inch holes up its bum will give it some sweeter notes.
    did it (3 of)..sounds sweet, but now get slight backfire down low.. on the compression.

    ??? leave it or tune up time?
    any comments and constructive abuse welcome. :)

    could also be looked at as a way to upgrade to new throats. :wink:
  2. leave it, theres is nothing wrong with the gurgle (or backfire as you call it), sounds mean :LOL:

    only really need to worry about a tune up if it's blowing smoke because of it
  3. Whack a K&N filter in it and you will be flying..

    Check also if the std ecu can be remapped, if so get it done..
  4. 1. no smoke..all good there.
    2. it actually lets out a 'back-fire' in the gurgle, when im using compression, gearing down.
    its not a massive back-fire..but it is one. and its not all the time.
    im thinking im fuelling it up too much, when i gear down..?

    thanks btw :)
  5. ??? standard ecu ?? :?

    (im not very smart...but i can lift heavy things) :LOL:
  6. ecu = engine computer

    controls the engine
  7. you would get the same with custom maps and a vance and hines (buggered the spelling up oh well), i love the gurgle, gurgle, pop under compression, always had it with custom systems on cars and bikes
  8. Pop out exhaust is after fire, Pop through induction system is back fire.
  9. thanks :)

    i have been on 'old-school' Enduro bikes all my time.
    no ECU's there.. :wink:

    so i have just learnt something new today!
    its a good day.

  10. i met a fella today at 'the local' who arrived on the same bike as mine. :)
    his was fully decked out in all possible bling, leather and a healthy set of cobra pipes. (mine is stock standard)
    he was more than happy to talk toys and give great info to me..a newbie to the Cruiser code.
    he gave me his email addy..cos he said he was thinking of changing his Cobra pipes to 'something-or-other-slash-cut-demon-pipes' to suit him...or what ever..?
    ...cool..!! if he offers them at a good price...they're mine!
  11. All vees frap and bang on the overrun. Only way to stop 'em is spend a billion Yen on R & D like Honda did.

    Then you came along with the Black & Decker and upset all their work :grin:.

    Live with it. It's harmless.
  12. It is a result of incomplete combustion - it can sometimes be cured by slight adjustment of idle mixture.

    BTW the expression is not "compression" but engine braking, or overrun. Try revving it less when changing it down - the excess fuel of a big "blip" on the throttle could easily be responsible if the problem is intermittent...


    Trevor G
  13. over the past couple of weeks, i have found out this was pretty much the reason for the overrun.

    with my change of bikes (from XR600 to VT750) it is a wee bit of a difference in riding style and donks to get used to.
    and get used to it i will

    thanks to all for your useful info
  14. o-kay then..lts get on with the game.... :)

    i had a good chat with my local Honda mechanic (who only talks thru his teeth, with a hardly audible 'yep and nup'...):roll:

    the fuel mixture was adjusted..due to my standard pipe mutilation..
    but still the odd fart was still coming from 'Marcelles' butt.
    he then suggested.. 'shooda-taken-the-intake-vacuum thingy off it too'..!?!?!
    so i asked him to draw a diagram of this 'thingy' and explain it a bit... cos i have a few days off, i will have a go at removing this 'thingy' that Marcelle doesnt need.
    the surgery was performed today, and i am happy to say...it was a great success!!
    no more 'back-firing'


    when i learn how to make my pics smaller, to upload on this great site, i will post a pic of the offending 'thingy' part. maybe then some one can make sense of what i have just been through?!
  15. 'duzzent madda'!
    new set of throats purchased. :grin:
    V&H slash cut shorts.

    (the missus gave the 'okey-dokey' for xmas)

  16. Hi you lot! You seem to know what you're talking about. I have been going to buy a new set of pipes for my 750 too but I am thinking the Black and Decker option might be the go. I am not after more speed just the noise. So hubby (who knows nuthin 'bout bikes really) wants to know where the holes should be, how big, etc etc. Could someone give me some advice on the matter. Much appreciated.....