Two things I've learned about torque and power.

Discussion in 'Motorized Bicycle General Discussion' started by Toadmund, Jan 22, 2012.

  1. Toadmund

    Toadmund New Member

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    Was looking at SickBikeParts.com and I learned something I was wondering about, the gear ratio on a shift kit. Apparently in low gear it is like having a 58 tooth single speed rear sprocket, that's sick! Major hill torque there boy.

    I am planning my second motorbicycle, and I haven't even built my first one! I ordered the motor yesterday, and I am getting a donor mountain bike from a guy I know.

    What I am inspired by is this:
    Ridiculousness: "Death Comes To Town" or "Middle Aged Dudes in the Hall"
    That devil got me fired up about motorbicycles, I wondered how I can make one of those! (that's my second motorbicycle inspiration)

    OK, thing I learned numero deux:
    Deburring the intake port and deburr and polish the exhaust to smooth out the fuel exhaust flow, and to not polish the intake because the turbulence atomizes the fuel better.

    Just wanted to share my knowledge growth curve.
    Thanks.
     
  2. Toadmund

    Toadmund New Member

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    3 things I've learned now, writing a post in the form of a question may get me more replies.
    Oh well.
     
  3. recon chris

    recon chris New Member

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    Lol no it’s not that. I didn’t reply because you said "not polish the intake because the turbulence atomizes the fuel better." By all means polish the intake this will make the intake flow smoother an increase the engines efficiency. The atomizing of the fuel is the job of the carb, and if it’s not doing its job well enough then it’s time to upgrade. Dellorto makes a good one. And a fun fact for you is that when the crank gets hot it will actually vaporize the fuel while it’s still in the crank case about to be transferred to the piston and that is the best atomizing you can possibly get. This is why your bike always performs better after it has "warmed up"

    Read "the tow stroke tuners hand book" you can download it free online or if you can’t find it I can send you the PDF. It has everything you need to know to get you submersed into two strokes. And once you read it you’ll be able to do real modifications like I’m doing check it out.
    http://motorbicycling.com/f3/getting-all-3-horse-power-out-36485.html
     
    #3 recon chris, Jan 24, 2012
    Last edited: Jan 26, 2012
  4. Toadmund

    Toadmund New Member

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    Thanks, I did read some of that post that you linked, I will get back to it.

    I think you may mostly be right about intake polishing, leaving it unpolished would create more turbulence but if it was polished you would get that fuel,atomized by the carbuerator in the cylinder more efficiently also the heat does have a lot to do with vapourizing the fuel.

    I want to do this porting when I get my engine, if I can wait long enough before I install it!

    Impatience rears it's ugly head!
     
  5. Chriscraft112

    Chriscraft112 New Member

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    If this is your first build I recommend adding lock nuts instead of using the standard nuts that come with the kit.You might also want to change your spark plug as the factory ones that come with them can be crap along with the factory 415 chain.-Keith
     
  6. Skarrd

    Skarrd Member

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    one of the thoughts i had concerning fuel atomization and weather or not to polish the ports was this:

    leaving the intake slightly rough does encourage a small amount of turbulance that in it's self, atomizes the fuel mix. as is the practice on car engines and other 4-strokes.

    however...

    we are dealing with a 2 stroke engine that has a very fast spinning crank, and a not so direct path to the cylinder that the air charge must take to get there.

    therefore, polish those ports because it needs all the help it can get! :) just my $.02 thought on it.
     

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