full throttle?

Discussion in 'Motorized Bicycle General Discussion' started by Howitt, Jun 20, 2008.

  1. Howitt

    Howitt New Member

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    Is it damaging to ride a motorized bike with an 80cc happy time motor at full throttle for a long time? I will be using my motorized bike to travel 24km to work and would like to try and get there as fast as I can.
     
  2. Dave31

    Dave31 Moderator
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    I have never held it wide open for a very long time. I usually will feather the throttle every now and then. I'm not sure if holding it wide open would hurt it, but the way these motors are made I would not.
    Maybe you might want to change the sprocket to get more speed?
     
  3. deacon

    deacon minor bike philosopher

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    I'm not sure about wide open all the time because frankly the bike scares **** out of me wide open. It isn't blowing the engine that scares me it's hitting that big pot hole at thirty miles an hour that does it for me.
     
  4. nitroscope8

    nitroscope8 New Member

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    I've been riding full throttle for a while. I see no harm. Just back off when the vibration barrier comes up.
     
  5. sisdavid

    sisdavid New Member

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    I drove to the hardware store wide open the entire time about 20 minutes. Was really fun. I would use about 5 ounces of good quality oil semisinthetic.
     
  6. Pablo

    Pablo Master Bike Builder & Forum Sponsor

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    Well balanced, well breathing 2-stroke gas ICE's do best in their powerband. Sometimes that isn't always full throttle.

    Tell me more about the bike. But from the start I would say you need more power to the ground and merely suggest the following:

    1) General tune, right oil mix, good spark plug and wire.
    2) Port and polish the intake and exhaust.
    3) Install an expansion chamber.
    4) Get a shifter kit and take advantage of gears if you can.

    I can do 40 mph in 4th gear and have yet to explore 5th and 6th.
     
  7. Skyliner70cc

    Skyliner70cc New Member

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    My reply:

    New engine not broken in: Holding the same throttle setting and/or load on engine will not properly break in your engine. A new engine needs a lot of variability in engine rpm and engine load. WOT and heavy loads and/or high rpm for short periods of time are essential.

    Broken in engine: WOT operation wtihout overrevving engine is just fine provided mixture is not too lean. When I lived at high altitude, WOT was I rode most of the time.
     
  8. Pablo

    Pablo Master Bike Builder & Forum Sponsor

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    Good points Skyliner
     
  9. Howitt

    Howitt New Member

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    larger sprocket gives more speed? interesting.
     
  10. Howitt

    Howitt New Member

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    what mixture ratio would you suggest I use for WOT for 24km in toronto?
     
  11. Howitt

    Howitt New Member

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    the bike is a Raleigh mountian bike with 26" wheels.

    thanks for the tips, I will follow them.
     
  12. Tj Bunch

    Tj Bunch New Member

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    Pablo Where do I get the shifter kit?
     
  13. Howitt

    Howitt New Member

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  14. motor_head

    motor_head New Member

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    smaller rear sprocket will give more speed not larger
     
  15. old motorbike

    old motorbike New Member

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    I geared mine to use low revs. Now, without headwind, I can back off throttle and still cruise at 25-33 mph. It may go a little faster, but only at wot. Sea level.
     
  16. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    Yes, gearing up will lower your rpm at any speed, but due to physics, your bike will only go so fast on any given amount of power.
     
  17. donuts31

    donuts31 New Member

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    WOT throttle and high rpm operation will naturally increase wear. Will it be noticeable, probably not for most of us. Friction is directly proportional to the square of piston velocity. If you normally cruise at 3000 rpm, and then take engine up to 6000 rpm, there is 4 times more friction at 6,000 rpm than at 3000 rpm.
     

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