Reeds

Discussion in 'Motorized Bicycle General Discussion' started by Cylon, Oct 14, 2015.

  1. Cylon

    Cylon Member

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    Hey all Im posting this thread to ask what the difference I can see if I added a reed to my engine it would be great if someone could post a video to show this also. Thanks ~Cylon
     
  2. Skyking

    Skyking New Member

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    In order to receive the most benefit from tha application of a reed, you should first port, and port match the cylinder, and piston. Add a performance carb, and exhaust system.
    With all this you should expect, an increase in power, and torque, which translates to crisper throttle response, faster reving, higher rpm's, greater acceleration, and higher speed. Improvements will be seen across the entire power band, but can be tuned to better low or high end power, but usually not both. It tends to be a trade-off unless you go all out with your mods.
     
  3. Cylon

    Cylon Member

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    Heres a link to the bike I'm referring too, its the third build. http://motorbicycling.com/showthread.php?t=60072

    Now with those mods to that bike what can I expect from a reed? Could you also post a video of before and after with the reed?
     
  4. Skyking

    Skyking New Member

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    The reed valve is really nothing more than a cork that functions automatically. It opens, and closes the intake track at the most opportune time, and helps to maintain crankcase pressure which compacts the air/fuel mixture by preventing any blowback through the intake track. If you compact the air fuel mixture, then you can get more air, and fuel into a given space. That being the crankcase, and transfer ports. It's a bit like having a supercharger, but without the drag on the engine that the pulleys, and belts would produce. You can further increase the pressure by decreasing the crankcase volume by utilizing "case stuffers", and stuffed crankshafts. It all really depends on how much time, and money that you want to spend on your motor. There is a trade-off however, and that being faster wear due to the increased pressures, which is mitigated somewhat by the cooling effects of a greater volume of fuel, and oil injected into the areas of wear. The expansion chamber does essentially the same thing, but with the exhaust track as compared to the intake track. The length, and shape of the header, chamber, and stinger work in concert to perform this function. The trick, and hence the science is to balance all this activity into a perfect series of exchanges in the combustion chamber, crankcase, and transfer ports in order to get the very most out of the given space.
    Savvy?
     
  5. Skyking

    Skyking New Member

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    oops, sorry wrong thread
     
    #5 Skyking, Oct 15, 2015
    Last edited: Oct 15, 2015
  6. Skyking

    Skyking New Member

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    It's really kind of mind boggling as to the amount of performance that can be squeezed(pun intended) out of a 50cc motor. Roadrace bikes that routinely run in excess of 110mph with 50cc engines producing somewhere in the neighborhood of 20HP at 17 to 18,000rpm's through transmissions with up to 14 gears. I guess I got the bug back in 1969 when I was racing a 100cc Yamaha, and a 2 cylinder, 12 speed, 50cc Suzuki was passing me. All you could hear was this high pitched whine(no silencers back then), and constantly changing gears up, and down. I've been fascinated with small engines every since.
     
  7. Cylon

    Cylon Member

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    well I guess then ill get a reed and see what kind of boost I can get when spring comes snow will be here soon. (couple of weeks)
     
  8. Cylon

    Cylon Member

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    Got the reeds in the mail will let you guys know how they run, I should be able to get the bike back on the road in May!
     

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