Motor teardown nightmare

Discussion in 'Motorized Bicycle General Discussion' started by Kevlarr, Jul 4, 2010.

  1. Kevlarr

    Kevlarr New Member

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    So after living with a bad top end vibration at about 32 mph that I could not get past (I'd hit the vibe point and the motor would bog down) I decided to try and balance my crank yesterday. The only thing that came apart the way it was supposed to was the front sprocket and the mag, once I got past those everything seemed to have been peened with a punch or something. I couldn't get the clutch puller threaded on because the threads on one side had a nice 1/4" dent in them so I ended up pulling the whole thing as a unit. Split the case and the bearings were stuck to the crank, you guessed it, both sides of the crank had peen marks on the ends of them from a punch. Somebody didn't want this engine to ever come apart!

    A little work with some emery cloth got the bearings loose but I think I may have damaged one, there's a little annoying squeak coming from the engine now but I can't tell if it's the crank bearing or the clutch. Guess I'll keep my rides close to home for awhile if the motor decided to grenade itself.

    On a good note though, the vibe now comes and goes around 25mph and now I can cruise around 35 with less vibration then I had at 30. :D
     
  2. corgi1

    corgi1 New Member

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    squeeks with the clutch pulled ,or engaged and pulling the bike down the road?
     
  3. Kevlarr

    Kevlarr New Member

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    (D) All of the above.
     
  4. mapbike

    mapbike Active Member

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    how did you "balance" the crank.....?
     
  5. Kevlarr

    Kevlarr New Member

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  6. corgi1

    corgi1 New Member

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    squeeking,,,,,,,could it be the clutch touching the inside of the clutch cover,,,wait a minute,,where is that philips screwdriver
     
  7. xzackx

    xzackx New Member

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    ive noticed my engine at about 25 or so vibrates really bad if i let it sit clutch in and rev it about half throttle my whole engine shakes and starts sliding out of placement on my mount right now my engine if hanging out onto my pedal im not sure if its supposed to shake that bad and goin down the road if u go down a hill should you pull the clutch in or leave it? it seems like its wantin to pull the engine faster then it wants to at idle it vibrates bad too goin down a hill with the clutch out i usually pull mine in it helps the vibe and sound
     

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