my exhaust system. will it be ok?

Discussion in 'Motorized Bicycle General Discussion' started by linnix13, Jul 2, 2010.

  1. linnix13

    linnix13 New Member

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    just made an exhaust system for my bike. any input would be apreciated seeing as the bike wont run until its finished in a week or so. will my system work?

    thanks
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  2. corgi1

    corgi1 New Member

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    ok, just an idea,,,,,If possible I would add another angle at the seat area and aim it about 45 degrees down clearing the rack for use,,also you will want some kind of heat protection for your leg,exhaust wrap ,or make a stand off heat shield ,or both(paint it black with high heat paint)
     
  3. linnix13

    linnix13 New Member

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    ok paint is a good idea. also i have it the way it is because im making a trunk that will cover the muffler and hold my gas tank. so all that will stick out is the silver tip

    the box is like this one i made for my moped a few years ago
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  4. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    I think if you add another three feet to it, it'll improve the performance!! laff
     
  5. Nashville Kat

    Nashville Kat Active Member

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    I think you're gonna burn yourself- other than that it looks quiet- but that's not rubber on the first section surely.

    Just how well does copper work? the parts are widely available....
     
  6. linnix13

    linnix13 New Member

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    my legs can take the pain! other than that, no rubber its the original manifold from the black cat muffler. my aim here isnt performance. i want quiet and classy, i will paint it all matte black and i will learn the hard way to keep my legs off the pipe! i used copper on my old bike build, here check the video out, it was rigged and stupid i know but copper works great! cost me 10 bucks and an hour of my time to make my current muffler. the one in the video i didnt even try

    YouTube - custom exhaust on 80cc bicycle engine
     
  7. corgi1

    corgi1 New Member

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    A rubber hose does make a smooth arch and looks good painted,,and fits in the copper 3/4 tube
     
  8. corgi1

    corgi1 New Member

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    hot leg,,the pipe may get hotter than a pan in a 350 degree oven
     
  9. corgi1

    corgi1 New Member

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    Oh and the angle down toward the pavement may be quieter(I forgot to write that)
     
  10. Goat Herder

    Goat Herder Gutter Rider

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    When I messed around with some tuned pipes on the china I was always amazed how much more peaceful and quit they got with the pipe ran to the back. A big plus is all that oil from the exhaust doesn't accumulate all over the bike. Always nice to see folks enjoying the hobby.
     
  11. linnix13

    linnix13 New Member

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    thanks! i found that out before too. further away is better. i want peace not speed. and the oil is a plus. i also found that rubber between the fins helps allot and so does some grease in the gearbox(its hard to et the right amount so the clutch wont slip though.)
     
  12. mapbike

    mapbike Active Member

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    You will have NO pulling power with that set up, way to long and way to much back pressure with the cat. muffler and the lawn mower muffler combined, but if you dont care if it will pull itself up a hill without you having to pedal it 2/3 of the way it should be just the way you want it to be, just a small amount quieter and lots of power loss.
    Good luck with your efforts.....
     
  13. KCvale

    KCvale Well-Known Member

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    In a word, no, it won't be OK.

    The exhaust on a 2-stroke is actually part of the intake too.
    This animation from SpookyTooth shows you better.

    [​IMG]

    With no expansion chamber blowback of fuel it goes out the tailpipe polluting like crazy, and it cuts your power and mileage drastically.

    I suggest you use a real pipe, then just add your mufflers after it.
    Just go real wide right after the little expansion chamber exit hole so as not to restrict it too much.
     
  14. linnix13

    linnix13 New Member

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    i have had other 2 stroke bikes like this. i looked into the expansion chamber and im not going to spend 60 bucks on one. i want simple. about pollution. i could care less!
     
  15. KCvale

    KCvale Well-Known Member

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    Simple is good.
    All I suggest is that you use the existing pipe, then mount, tweak and add to the end of it all you want.

    It is not the most efficient expansion chamber but it does function as at least your 2-stroke version of a 4-strokes exhaust valve via tuned back pressure.

    Just attach your final pipe to the little end of the stock pipe is all.
    But hey, your bike bud, just trying to help ;-}
     
  16. linnix13

    linnix13 New Member

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    hey. i got out riding it today. with the after muffler on it is very quiet and comfortable. it is decently powered. i accidentally knocked it off with my foot and i gained but loads of power. without the after muffler its every bit as powerful as my old 2 stroke with the stock exhaust was! but its loud. i dont want loud. i will be putting the after muffler back on. thanks for all the3 input guys!
     
  17. Kevlarr

    Kevlarr New Member

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    You plan on putting the muffler INSIDE a wooden box and carrying gas in there too?!!!???

    You're extra muffler on the end is pretty much overkill, I have my muffler in back at the end of an expansion chamber and the intake is louder then the exhaust.
     
  18. linnix13

    linnix13 New Member

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    right now the loudest part of my bike is the gears making the whirling noise. the muffler will go under the wooden box. that after muffler removes all the pops and pings the 2 stroke makes!
     

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