Need help converting to all belt drive.

Discussion in '4-Stroke Engines' started by KeepOnKeepnOn, Mar 11, 2013.

  1. KeepOnKeepnOn

    KeepOnKeepnOn New Member

    I built my motorbike about 4 years ago. Went with a 4 stroke and modified the intake as well as exhaust with the top priority being to make it quiet. When I fired it up for the first time I was stoked on the stealthiness... then I took it out for a ride and the gear box screamed like a banshee. I tried greasing it all up, filled it with 90 wt, even built a closed cell foam cover for it but it was way too loud. So I threw it in the corner of the garage and it has sat ever since.

    Recently my interest in motor biking has been renewed and I tore off the gear box, breaking the outer cover in the process. The clutch shoe had a deep gouge in one and a lesser gouge in another, the third had a tall lip on it. Factory direct crapola. I'm not sure if it was the clutch or the gears making all that noise but either way, I'm done with that set up.

    Since then the 4g and the EZM have come out. Some cheap Chinese 18" rear wheel sheaves have come on the market as well. I want to go all belts to make it as quiet as possible but still gas powered.

    Question #1. Will the 4G bolt right up where my old gear box was? The motor is a Hua Sheng 49cc, the only identifying stamp I could find was on the block under the clutch "142F". The shaft is keyed and I measure it as machined down to 9/16 on most of the exposed area and 11/16 closer to the engine... do we call that a "5/8 keyed shaft"? Its definitely not tapered, is there just the two types, tapered and keyed?

    Question #2 Any recommendations on what size and where to get the pulley to replace the 11t sprocket and belt I will need to join the tranny to the rear wheel sheave?

    Thanks for the help
    Last edited: Mar 12, 2013

  2. grinningremlin

    grinningremlin Active Member

    I can tell you my GEBE with a 2 stroke whines like crazy. Can you post a link to the sheaves you're talking about?
  3. KeepOnKeepnOn

    KeepOnKeepnOn New Member

  4. darwin

    darwin Well-Known Member

    Talk to some whizzer folks, some of those whizzers are belt driven and there must be a place to get parts.
  5. Racie35

    Racie35 Member

    the sheaves you see are 15" keep that in mind while selected pulley size etc...I dont know if the 4g bolts to that engine...if it does youre halfway could always jackshaft any more needed reduction if needed.
  6. KeepOnKeepnOn

    KeepOnKeepnOn New Member

    Hmm, the sheave by itself is 15", while the fully built wheel says "overall diameter is about 18.11 inches" which could mean the sheave or the wheel rim.
  7. Quenton Guenther

    Quenton Guenther Motored Bikes Sponsor

    We make a belt drive system for most 4-stroke motors. It is the EZM Q-Matic drive or the new Pacesetter version. We use a special MAX Torque clutch made with a 2.5" output pulley and is normal connected to the rear wheel via a Whizzer belt sheeve [15"].

    You are welcome to contact me directly if you need a custom built drive, as we have attached our drive system to HUNDREDS of different types of 4 stroke motors. I will attach pictures of my latest motorbike with the total belt drive [both primary and secondary use a belt].

    We make adapters to fit all the HS crankshaft sizes, including the 14.8 MM, 15 MM, long tapered, and shart tapered sizes. Our stock Q-Matic drive bolts directly to the entire HS series of motors, and can be custom fitted to about any 4 stroke Horz. motor. We ship drives everyday [hundreds in stock] to fit allmost all small 4-stroke motors.

    Have fun,

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    Last edited: Mar 20, 2013
  8. KeepOnKeepnOn

    KeepOnKeepnOn New Member

    Very cool looking bike. I bet its nice and quiet with the belts and the big muffler. I have been in contact with two of your dealers who are right in town here.
    What is the gear ratio you are using in the transmission when you use the 2.5" output and 15" sheave?
  9. Quenton Guenther

    Quenton Guenther Motored Bikes Sponsor

    Secondary ratio is 6.31914893617 X 1

    Stock primary ratio on the Q-Matic is 2.73529.

    Over-all ratio on the stock Q-Matic with the belt drive is 17.287048936 X 1
    Over-all rato on the stock Q-Matic Pacesetter belt drive is 18.10347 X 1

    Have fun,
  10. MotorBicycleRacing

    MotorBicycleRacing Well-Known Member

    fast looking bike Quenton,
    Looks like a Schwinn jaquar.

    Is that a bicycle rim that you are using for the sheave?
    How do you have that attached?

    I don't see any brakes on the bike? dirt tracker? :D
  11. Quenton Guenther

    Quenton Guenther Motored Bikes Sponsor

    Rim is from Whizzer Sportsman. Laced to a vintage New Departure coaster brake [works well]. No front brake or front suspension to save weight.

    Reversed cone tuned exhaust, adjustable CDI ignition, adjustable main jet, adjustable ratio Q-Matic Pacesetter drive w/belt drive secondary, electronic tachometer, electronic speedometer.
    Schwinn frame.

    Have fun,
  12. EZMJon

    EZMJon Member

    I got to ride that bike. That thing is CRAZY QUICK! It definitely turns some heads when your flying down the road.
  13. MotorBicycleRacing

    MotorBicycleRacing Well-Known Member

    Cool, post up some video.

    You EZM guys should get one of your dealers to represent EZ Motorbike
    at the SoCal Motor Bicycle Race on April 13th in the 50cc 4 stroke class.

    Win races on Saturday, sell gearboxes on Monday or something like that. :D