4G Gearbox

Discussion in '4-Stroke Engines' started by dougsr.874, Sep 4, 2012.

  1. dougsr.874

    dougsr.874 Active Member

    I have researched this but can't seem to find the full answer...Question: Is the oneway bearing bad in ALL of the 4G gearboxes....Gasbikes is advertising an improved bearing ,. is that true....Bicycle-engine.com says they will have the improved bearing in the middle of Sept......Info please

  2. MotoMagz

    MotoMagz Member

    They are all bad.you can JB weld or weld it solid.Or wait til a solid pully is avalible.If you are going with the 100 tooth (5 hole) I think kings sells those seperate in the 100 th solid you could swap yours out.
  3. dougsr.874

    dougsr.874 Active Member

    More questions

    I don't know what you mean by 5 hole...if you mean the big belt driven pulley, mine already has 5 holes..If you weld the bearing what function do you lose if any...Is the oneway bearing the one in the center of the big pulley....does the 100 tooth fix the problem
  4. MotoMagz

    MotoMagz Member

    83.jpg the oneway bearing is in the center.It is used with 4G 's that do not have a freewheel output sprocket or the 10 tooth sprocket.So if your 100 tooth has a oneway bearing it might have a 10 tooth out put sprocket?If it has a 11or 12 tooth out put sprocket you will not loose any thing.If the 100 and the 10 are both solid(non freewheel) you will have a hard time pedaling.
  5. dougsr.874

    dougsr.874 Active Member

    Thanks so much for the info....I checked out what I have....it has 6 holes in the big main pulley and ll teeth on the final drive sprocket...so can I assume that mine is ok to ride?????? (I know what assume means)
  6. Barry

    Barry Member

    I had to fuss with the 4G clutch for a week before I got it squared away then the one-way bearing failed, I did the JBWeld trick to it, it failed in about 10 miles, I then REALLY welded it, it's working now but I've had it with that gearbox and am getting ready to order a Q-Matic replacement.
  7. Quenton Guenther

    Quenton Guenther Motored Bikes Sponsor

    Asking a freewheel to work on a motorized bike is somewhat problematic. This is the reason we have the "freewheel" action built into the clutch. The Max Torque clutch used in the Q-Matic drive supplys the necessary "freewheel" action without using the problematic mechanical system.

    When riding the bike [with or without the motor running] using the Q-Matic drive, only the rear chain and the outer clutch hub turn, unlike other drives which turn almost everything in the drive. Using a mechanical "freewheel" is necessary on systems using a T-belt because often the teeth rip off the belt when reducing the speed.

    The Q-Matic was designed to provide "motor braking" until approx 18 MPH, at which time the clutch dis-enguages [using a mechanical freewheel would remove this feature]. "Motor braking" is an import feature with the Q-Matic as everyone knows bike brakes aren't the greatest, and the system helps reduce brake wear and stop much quicker.

    Just a little American engineering in the Q-Matic design to make it work longer and better!

    Have fun,
  8. The_Aleman

    The_Aleman Active Member

    I've had a solid-pulley 100T 4G with 11T freewheel for over 2 years now, never once had a problem with it. My brother had way more problems with his (early) Q-matic in 2 years.

    Hopefully the vendors ordering 4Gs will go back to the solid pulley models, and not the freewheel pulley junk.

    My 4G smokes Q-matics with same engines. And Quenton, no one here asked you how a Q-matic works. Please keep your advertising out of 4G threads. Kthx.