Legally restricted output.

Discussion in 'Motorized Bicycle General Discussion' started by Ludwig II, Aug 1, 2012.

  1. Ludwig II

    Ludwig II Well-Known Member

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    Does anybody have any experience of restricting 50cc 2 strokes to suit their local laws? I'm going to have to get an engine with a genuine 2.5bhp down to 1.3 to get through the approval process, and although I think I know how to do it, I wonder if it will be enough.

    Step 1 is to find the smallest carb in the shop and fit that. Step 2 is to introduce a positive stop to the twistgrip so it can't open the carb much anyway. Step 3 is restricting the exhaust outlet, with the option of reducing the "inlet" side of the silencer. Step 4. Use Super Unleaded for it's slow burning properties.

    Anybody got any more ideas?
     
  2. wheelbender6

    wheelbender6 Active Member

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    Are they going to dyno your motorbike? I don't know any way to determine your power output.
    How's the summer home in Nueschweinstein doing?
     
  3. Ludwig II

    Ludwig II Well-Known Member

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    The plumber said they'll be back next week, so I've had to postpone the plastering, and don't even talk to me about golden swan boats!
     
  4. Ludwig II

    Ludwig II Well-Known Member

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    I think they must dyno, as the regs state I can only have 1kw/1.3bhp and a design speed of 16mph for the most basic class of moped.
     
  5. biknut

    biknut Active Member

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    I think just the throttle stop is all you need.

    I would first find out how they plan to test the power output. I think it's unlikely they'll try to dyno it.

    I think they'll probably just ride it to full speed at most.
     
  6. young grease monkey

    young grease monkey New Member

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    dude they aren't going to dyno your bike, but they might test speed so put on a throttle stop, test it with a gps and make it so you can only go 14 or so when you go to get it registered, then unleash it. if cops stop you, you can say it is made to go 16 so it must have been a radar error. the police aren't going to dyno your bike either, they don't have enough money to spend on an expensive machine they will never use that takes up tons of space.
     
  7. Ludwig II

    Ludwig II Well-Known Member

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    I don't think the local testing centre has enough space to speed test a tea trolley, this is urban Britain we're talking about here. I think I will take a trip to the centre and actually ask somebody there what they do. For an organisation with their clout and finances (paid for out of £££ registration and test fees) they may well have a dyno on the premises.
     
  8. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    I concur... A throttle stop would be the easiest way to do it!
    Pass the test; take it off & don't get caught speeding. ;)
     

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