Smaller Sprocket For Single-Speed Bikes

Discussion in 'Motorized Bicycle General Discussion' started by 5-7HEAVEN, Feb 8, 2009.

  1. 5-7HEAVEN

    5-7HEAVEN Well-Known Member

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    On "The Whizzard's" maiden voyage yesterday, I rode to my jobsite and back, then motored west to Home Depot for stuff, a distance of 25 miles. The bike performed flawlessly; this surprised me cuz I rescued it eight days ago from months of neglect in an open bike lot. Changed oil and crumbling fuel lines, tightened stem, added air and awayyy she went!:grin5:

    Brakes need attention but that's another post.

    My question is if it's possible to change to a smaller sprocket on single-speed bikes. This Whizzer is freewheeling; it has a small drum brake, not a coaster brake.

    However, I'd also like to swap to a smaller sprocket on "The Dragon Lady", my twin-engined cruiser with coaster brake.

    The reason is that both bikes need my pedal-assist during midrange and top speed. My other dual-engined monster "The Iron Dragon" has five speeds and fifth gear REALLY helps pull the bike, even at speeds over 30mph.rd.

    What should I look at changing, the freewheel sprocket or the crankset?

    IMO, adding more pedal-assist to a Whizzer bike or a motorized coaster bike would definitely enhance both bike's midrange and top end performance.

    Of course low speed pedalling would suck without the engine , but I can live with that.
     
  2. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    Change to a bigger crank sprocket!
     
  3. 5-7HEAVEN

    5-7HEAVEN Well-Known Member

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    Venice, so how many more teeth larger would make a difference?.bld.
     
  4. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    I'm not sure... ?? If you're planning on pedaling to assist the engine at 30+ MPH... you should probably add plenty!!
    Maybe take the top gears off of a old 21 speed or something??

    dnut dnut dnut dnut
     
    #4 Venice Motor Bikes, Feb 8, 2009
    Last edited: Feb 9, 2009
  5. 5-7HEAVEN

    5-7HEAVEN Well-Known Member

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    Another member recommended 52t chainring/18t sprocket, so I'll try that.
     
  6. HoughMade

    HoughMade New Member

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    You have to worry about your chin guard...but the question is, what are you running now? I assume the front is 44t, correct?

    My Husky wheels came with a 22t rear sprocket assuming a heavy bike. If you have that, just a 17 or 18 for the rear and see where that gets you.

    For me...if I wanted to pedal, I would have left the engine at home. I run a front 36 with a rear 19 so I can get my beast off from a standing start.
     

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