Quieter muffler?

Discussion in 'Motorized Bicycle General Discussion' started by SeattleMike, Mar 25, 2008.

  1. SeattleMike

    SeattleMike New Member

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    Does anyone know of a quieter exhaust setup? I don't want to wake up my neighbors at night when I come home at 12am.

    Also, I'm using a 16:1 gas/oil ratio like my instructions said for the break in period, will I get a decent power boost when I go to 20:1 after the break in?
     
    #1 SeattleMike, Mar 25, 2008
    Last edited: Mar 25, 2008
  2. paul

    paul Active Member

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    i did and you will feel difference in power when it breaks in. norman made me a custom exhaust for my bicycle engine that is very quite untill you go full throttle then you get a nice deep sound. its awesome
     
  3. SeattleMike

    SeattleMike New Member

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    Could you post or email a picture, or more info on this quiet exhaust setup? I'm interested in making one myself, or buying one from someone.
     
  4. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    Mike, how about exploring aftermufflers?

    They can be made out of nearly anything....use your imagination. I've seen 'em made from fiberglass stuffed drink cans to silicone bulbs with holes all around them.

    I'd run a tank of 16/1 then go to 20/1 for a few tanks then go to at least 24/1. Personally, I run 30/1 in the older bushed engine, 32/1 in the bearing engines.
     
    #4 Bikeguy Joe, Mar 26, 2008
    Last edited: Mar 26, 2008
  5. SeattleMike

    SeattleMike New Member

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    Sounds like a neat idea, making one out of a beer can or something. I use ceramic wool to insulate my woodstove chimney, maybe I could use that. I'll give it a try next time I feel like getting creative!
    Would wrapping my existing (stock) exhaust pipe and muffler with ceramic wool or fiberglass insulation quiet it down a bit?
     
  6. deacon

    deacon minor bike philosopher

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    I'm thinking lawn mower muffler at the end of the stock one... might be interesting.
     
  7. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    That would definitely be worth experimenting with.

    I tried to make a muffler when I was a kid and we filled a tobacco can full of steel wool and stuck it on the 2" stub of broken head pipe on my friends Indian 100cc dirt bike.....instant fire!

    Do not use steel wool.
     
  8. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    Better use a 24 oz. can, or two.
     
  9. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    Other ways to quiet the bicycle motor kit are to-

    Place rubber blocks between the cooling fins on the head and cylinder.
    If you experiment with a better air filter/box you could quiet any two stroke nicely.
    Make sure you have proper lube and tension on your drive chain-3/4".
    Secure all "sheet metal" such as fenders, chain covers, reflectors, seat springs, or anything else that can vibrate and make noise.
     
  10. SeattleMike

    SeattleMike New Member

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    Anybody have cool ideas how to make an airbox? Will you post pictures of your own custom airbox? Maybe I'll make one out of a budweiser can- just poke holes in it and insulate it with something.
    Do 2 strokes usually make noise because of sound going out the airbox?
     
  11. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    Sometimes, half the sound you here can be intake sound.

    Bigger, baffled boxes are pretty quiet.
     
  12. toytime

    toytime New Member

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    Just get the right size "rad hose" that slips over the carb and hose clamp it in place. If you really take your time, you will find one with all the right curves in it so that it leads under your seat. Most if not all motercycles use this method with an air box under the seat or gas tank.
     

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  13. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    That would be a pretty small radiator hose, but I get the picture.

    Any airfilter is better than what we have fo' sho'!
     
  14. paul

    paul Active Member

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    48mm is what you need for size for air filter. i got one of the cone ones but it will not fit in the small space i have. you need about 4" clearance behind the carburetor
     
  15. paul

    paul Active Member

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    sorry mike didn't see your post. this is the one norman and bob made for me and it is awesome. for in the neighborhood if you do not open it up you cannot hear the exhaust over the engine. it is that quite. you open it up and it has a nice deep sound and not the weedeater sound. here is a picture of the pipe

    [​IMG]
     
  16. SeattleMike

    SeattleMike New Member

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    Thanks for posting this pic Cruiser, its nice to know that there is a setup that reduces noise but doesn't reduce power much. I am a bit irritated by the telltale noise of the 2-stroke, it's loud!

    I don't have a great grasp on 2-stroke exhaust technology, I don't fully understand the benefits of the bladder-like setup and why the pipe diameter sometimes is reduced. Does anybody know a website that explains this, or know of a good book on 2-strokes?

    I'm working on creative ways to modify my air intake right now, I'll post a pic when I get it setup.
     
    #16 SeattleMike, Mar 29, 2008
    Last edited: Mar 29, 2008
  17. paul

    paul Active Member

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    the pipe actually increased the power on low end big time and top end it increased about 3mph. i am really happy with it. norm and bob are awesome
     
  18. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    I don't have a great grasp on 2-stroke exhaust technology, I don't fully understand the benefits of the bladder-like setup and why the pipe diameter sometimes is reduced. Does anybody know a website that explains this, or know of a good book on 2-strokes?



    two stroke tuning - Google Search
     
  19. Pablo

    Pablo Master Bike Builder & Forum Sponsor

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    I now want to start opening my bike up a bit!

    Air Intake: 48 mm = 1-28/32" - hmmm what have you found that fits this? Or is it easier to adapt up to 2"? And what the heck do you clamp to - the flange on the carb is tiny?

    Exhaust: I REALLY want a pipe like cruiser's for better low end grunt and top end flow, the chamber allows pulses to work for your engine.

    How Two-Stroke Expansion Chambers Work, and Why You Should Care.
    Dan's Motorcycle "Two Stroke Motorcycle Exhaust Pipes"

    I was looking at the DAX $19.99 HiPo exhaust as well. I may drill/cut my current set-up, just for fun.

    Noise: My exhaust is sorta noisy when standing by and revving it, but not really THAT loud when buzzing by. OTOH it isn't the silent beast either. A chamber pipe with an exhaust tip would be the best of both worlds, IMHO.

    Noise II: I've got some sound deadening stuff for the clutch chamber and some silicone rubber tubing hunks to form fin sound deadener.
     
  20. Pablo

    Pablo Master Bike Builder & Forum Sponsor

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    BGJ beat me to the Googlizer. Put you get the point! ^5
     

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