Exhaust leak by clutch lever

Discussion in 'Motorized Bicycle General Discussion' started by soup325, Feb 19, 2011.

  1. soup325

    soup325 New Member

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    Hi All,

    After purchasing a SBP hardware kit, my 2 Stroke 48cc has exhaust leaking out behind the clutch lever area.

    I think I may have over tightened it, that I have cracked something inside?

    I notice this on start up when in my garage, white smoke comes near the little 10t sprocket. I not sure exactly where yet. But I also have pressurised gas going out of the clutch cover. I noticed oil on my mudguard in a funny spot. Which lead me to the leak.

    Is this normal? Have I broken something? I think the engine has also lost power from this.
     
  2. bairdco

    bairdco a guy who makes cool bikes

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    that's weird. never heard of that problem before, and it definitely shouldn't be doing that. can you post pics?
     
  3. whelan wheels

    whelan wheels Member

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    hello there,remove your clutch cover off your motor and then inspect the seal just under your drive gear to see if it leaking,and if it is then that means you have a blown oil seal on your crank shaft of your motor. had a simuler problem on one of my motors before.my oil seal blew out and exhaust gasses where exiting around the primary 10 tooth drive sproket. thats what it sounds like the problem you have there. might be a manufacturing defect in your motor. xct2 cflg

    p.s. thats on the right side of your motor.
     
    #3 whelan wheels, Feb 20, 2011
    Last edited: Feb 21, 2011
  4. Creative Engineering

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  5. soup325

    soup325 New Member

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    Thanks for that. That area sounds like where the problem is coming from.

    It explains why I cant tune it, and the down on power when under load.

    I was hoping I wouldnt have to strip the motor down after 5 months of running.

    More fun for me
     
  6. Creative Engineering

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    Soup,

    As a quick check; I would definitely check out what Whelan suggested.

    If you remove the clutch cover, and fuel spills out...it's going to be a bad crank seal.

    From what you have described: it's more common that the case gasket has blown out, but I would definitely start by having a look at the seal. You might get lucky and not have to split the cases.

    Jim
     
  7. soup325

    soup325 New Member

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    After a second look. There is goop in the clutch gears side of the engine, that is not as thick as grease. After looking at a few other posts, combined with my clutch slipping problem, I think it is the oil seal on the crank.

    Now to find a seal that will fit and that is not made in china
     
  8. camlifter

    camlifter Active Member

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    i'd bet a dollar it's the center case gasket, the out put shaft may or may not have a seal, even if it does it's not made to stop engine pressure from getting out, just the grease on the clutch spring and shaft.
    pressure from the crank case is getting into the clutch area and leaking out.
     
  9. soup325

    soup325 New Member

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    Took it off today. It was the Oil seal on the output shaft (202 bearing).

    Im now looking for a seal size 14.8x27x7.5

    I will get a case gasket at the same time. Does anyone know where to get a heavy duty one?
     
  10. soup325

    soup325 New Member

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    Everything is up and running again.

    I got an oil seal with 'Australian Made Rubber' for AU$9.50. From Rock Solid Motors in QLD. Also, installed a new set of clutch pads. The pads soaked up a lot of oil and I could not get any grip. So new pads have solved the slip. Now for some new brakes.
     

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