More engine problems.

Discussion in 'Motorized Bicycle Trouble Shooting' started by xXNightRiderXx, Feb 15, 2017.

  1. xXNightRiderXx

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    So, I have a problem with my motor. Well, a couple actually. My muffler fell off while riding, not the pipe, just the muffler, and I wonder if it is detrimental to my engine at all? Also, I have an issue with my motor tilting under power and even more while starting. I have gas bikes super mounts, if that makes any difference.
     
  2. malatious

    malatious Member

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    It's hard to tell without seeing exactly how the mounts work but anything with that much rubber would most likely cause to much movement. You could try and tighten the mounts up as tight as you can get them and see if that helps. Movement is not good and will cause all types of problems from chain misalignment to frame failure. Rubber mounts can sometimes cause more vibration than hard mounts. I have never had my muffler apart but I think there is a nut at the bottom that holds part of it together. If your engine is moving around a lot it may have caused your muffler to come apart as well.
     
  3. crassius

    crassius Well-Known Member

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    I doubt you'll find many here that would ever use a rubber mount. They tend to shake things apart.
     
  4. xXNightRiderXx

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    The muffler fell off at the top, where the pipe ends and the muffler casing begins. I noticed a slight increase in low end torque aside from increased noise. I will try taking off the front end rubber mount, or I might remove them altogether and just use rubber pads. That seemed to work best for vibration and lack of movement. Also, I don't know the cause of this, but my engine seems to bog down a bit while idling. I just recently had it die at a traffic light. RPMs too low perhaps?
     
  5. Chaz

    Chaz Active Member

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    You can get that muffler welded back on to the header pipe. Not healthy to run an open pipe like that.

    Get rid of the rubber at the mounts. Rubber actually increases vibration in this application.

    Idle is probably a bit too low, adjust as needed.
     
  6. Potato_In_Exhaust

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    Make sure your carburetor didn't vibrate itself loose exposing the slits causing an air leak ..... that will make your bike die when trying to idle.
     
  7. xXNightRiderXx

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    Ok, so one of my mounting studs just sheared while trying to start. Clutch is also slipping, and there is no evidence as to why. :-||
    I should add that it started slipping when I reinstalled it. I took it off for a while cause I was out of gas and had no money. I feel like I should completely disassemble my clutch to diagnose it.
     
    #7 xXNightRiderXx, Feb 16, 2017
    Last edited: Feb 16, 2017
  8. crassius

    crassius Well-Known Member

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    clutch could be simple adjustment - I'd do nothing until motor was solid in frame
     
  9. xXNightRiderXx

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    Ok, I took off the rubber on the front, which dramatically reduced movement. I just cleaned my clutch pads, and it is still slipping. I tightened the flower nut, still slipping. I'm thinking of just replacing the clutch entirely if I can't find a solution.
     
  10. sbest

    sbest Member

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    That is called: "The More Money Than Brains Solution".
    And if you don't have a lot of money, well, it ain't lookin' good!
    Read up on what that flower nut does and the proper way to adjust it.

    Listen to these guys here.
    They were right about the mount weren't they?
     
  11. crassius

    crassius Well-Known Member

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    how much 'grab' the clutch had depends on how great the distance is between locked and unlocked position of clutch lever if it is adjusted right - don't forget to look for fuel that spilled from carb onto clutch when motor was shaking
     
  12. xXNightRiderXx

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    Thanks for that suggestion. I'll see if that's the issue. Also, would an automotive shop be able to extract my right side mounting stud? It sheared off while I was trying to start it up.
     
    #12 xXNightRiderXx, Feb 17, 2017
    Last edited: Feb 17, 2017
  13. sbest

    sbest Member

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    A machine shop might be a better choice.
    Tell them if you used Locktite on it, so they know to use heat.

    I was a machinist for a while. We were where the mechanics took the broken studs.
    It is easier and cheaper to take it before making a lot of failed attempts to remove it.
     
  14. crassius

    crassius Well-Known Member

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    having it done might be very expensive (possibly more than a new motor)

    look around the board for how to do it and also check the area about alternative mounts to work out a different way to mount it
     
  15. xXNightRiderXx

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    Crassius, how much travel should be in the clutch lever? I like to keep things tight for better control. I just installed a new clutch cable, but haven't attached it to the clutch arm. I have about six inches of free cable to play with.
     
  16. crassius

    crassius Well-Known Member

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    search on the board here for the step to adjust cable/clutch (I've typed them all out a hundred times)

    be sure to start with the clutch arm just touching the bucking bar while pointing almost straight back by loosening or tightening flower nut to get that right
     
  17. xXNightRiderXx

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    Just happens that a few bearings in the clutch are missing. How do I access the bearings and what size are they? I'm going to replace them with carbon steel equivalents.
     
    #17 xXNightRiderXx, Feb 18, 2017
    Last edited: Feb 18, 2017
  18. crassius

    crassius Well-Known Member

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    if you're talking about the little 'grain of sand' sized bearings in the clutch hub, there are almost always some missing - opening that and pressing it back together is a real job that I only did once to see how it all went together - took several tries to keep from losing a few bearings during the process

    I'd say ignore it as it only causes a problem if something gets in there and locks it up.
     
  19. xXNightRiderXx

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    Then the only way my clutch will spin freely is if I get a new clutch wheel. Am I correct? I don't feel comfortable running a spinning wheel at 25mph with missing bearings. It's asking for trouble. I have some heavy packing grease I could use as a temp fix. It will melt at high temperatures, but I used some on my drive chain and it worked very well. Also, I'm pretty sure that as the clutch is already locking up, opening it up won't much of anything.
     
    #19 xXNightRiderXx, Feb 18, 2017
    Last edited: Feb 18, 2017
  20. MotorBicycleRacing

    MotorBicycleRacing Active Member

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    If you have a drill motor and an 1/8" drill bit it is fairly easy to remove
    broken off motor studs.
     

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