Clutch problems - please help!

Discussion in 'Frame Mounted Engines' started by decompiler, Apr 23, 2008.

  1. decompiler

    decompiler Member

    The fact that I still know so little about motorized bicycling will become very apperant when you read this:

    I am trying to thread my chain through so that I can fit the chain. But even with the clutch plate on (and even with the clutch activated I guess...), the engine will only turn an eigth of an inch and stop. It won't turn any more. I know I must be making a newbie mistake. I even reinstalled the clutch plate with the arm on it and put the thing into the activated position like all the faqs and .pdf files tell you to do. But the motor is still locked up. It's a factory test-fired motor with all the tale-tell signs it works correctly.

    So what am I doing wrong? What is the trick to getting the clutch to activate so that the chain sprocket on the engine turns freely?

    I know I must be making a novice, newbie mistake and I appreciate your help!

    Last edited by a moderator: Apr 26, 2008

  2. graucho

    graucho Active Member

    If I read this correctly, you want to pull in the clutch lever on the handlebars and be able to roll or ride and pedal the bike, like a normal bike.
    So, if you grab the clutch arm by hand, and push it inward tward the center of the bike, you still cant roll or disingadge the clutch/sprocket? correct?

    Then we can go on from here....
  3. decompiler

    decompiler Member

    Well, actually, I have a piece missing from the wire that connects to the clutch arm (it's in the mail!). So I haven't been able to use the hand grip yet.

    I still should be able to make the clutch rotate freely without the handle thing connected, right?
  4. graucho

    graucho Active Member

    Bend over and grab the clutch rod and push it in by hand inward tward the center of the bike. When it is pushed inward (it will push very stiff and hard) it will put the clutch in neutral. And then you should be able to spin the small gear. Or be able to push the bike, if the chain was on.___see photo
    When I re-read what i wrote, and the way this is written, sounds kind of "kinky" Hehe

    Attached Files:

    Last edited: Apr 23, 2008
  5. decompiler

    decompiler Member

    Thank you groucho.
  6. My chain snapped yesterday. Luckily,I keep a length of chain and my chain cutter in my tool pouch. So I switched my gas cap so I can flip her upside down and proceeded to work on my bike. I had some difficulty too with threading the chain so I removed the clutch lever housing exposing the sprocket and with channel locks I GENTLY grabbed the chain at the top of the sprocket to the little shaft in the middle and GENTLY turned it in till the chain went around. I would also imagine of you don't want to use channel locks,you can always just remove your spark plug and it should move a bit better.
  7. decompiler

    decompiler Member

    Well, my small sprocket will not turn. How is that metal dowl and bearing supposed to act? I tried poking on the rod thinking it was supposed to push inwards but it's just THERE. It doesn't move or give. I can push on it and it doesn't do a thing. It's supposed to do SOMETHING, right? The clutch arm is supposed to press that small rod inwards activating (or deactivating) the clutch, right? What if the ball bearing inside the clutch isn't as far down the clutch mechanism as it should be? I am scared to just put my screw driver in there and jam the bearing back down because nothing may be wrong in the first place.

    Could the motor have jostled something loose inside that clutch housing during shipping? From the opposite side, with the big/little wheels, it looks perfectly normal. Just that my engine's not turning.
  8. graucho

    graucho Active Member

  9. decompiler

    decompiler Member

    Well, I took out the spark plug and the engine rotates freely - thankfully! Graucho and Large have been a big help to me. I think I learned my first big lesson today with removing that spark plug. You can really tell I'm still green around the gills!

    As for the rod in the clutch mechanism, it still won't give. However, just as soon as I get some shut eye, I will wake up and read up on graucho's link and work on it again.
    Last edited: Apr 24, 2008
  10. fatboy67

    fatboy67 Member


    Hi First before trying below try,,,Take the clutch cast cover of then push the clutch arm across to disengage the clutch then just with a screw driver just knock the pressure plate a bit may be the spring is stuck and not pushing the pressure plate out. You see the clutch arm will push the screw bit in the middle of your pressure plate but it's the spring that actually pushes the plate out. Sometimes the plate might not sit exactly in the middle of the fly wheel.
    OR what about try this take you pressure plate off and see if the back wheel can now free wheel. May be the adjustment on the clutch isn't correct
    I have written this at 100 miles hr hope it sort of makes sense.
  11. autobo7

    autobo7 Member

    I was reading this and though i would give you my 2 cents, I assume you are pushing on the little rod in the middle of the sprocket and that is what wont budge? I doubt there are many poeple who could push that in by hand its hard enough with the leverage of the clutch arm. So i would guess that there isnt any out of the ordinary there, and if you are trying to feed the chain through the little sprocket for the first time you need to have the plate taken off the has the clutch lever on it, so you cant use that to pushing the clutch either.

    When I did it I pulled the spark pluge and just used a flat screw driver between the teeth of the sproket to move it, it will still be a bit tough but it will work.

    If you really want it to move easy this will require a bit more disassmebly... and im am also guessing you have the chinesse 2 stroke? On the other side of the engine there is the clutch cover with 5 or 6 screws in it. Remove them and then the cover will come off. You will see 2 gears, on the larger gear is the clutch, remove the very tiny brass set screw in the 'star nut' and the unscrew the star nut too. This will take the presure plate off and the little sprocket on the other side will move unimpared, but i think the screw drive thing should work well enough
    Last edited: Apr 24, 2008
  12. Scottm

    Scottm Guest

    I use a socket/ratchet to turn the nut that's holding that sprocket on, so I can feed the chain on. Taking the spark plug out is most helpful.
    Ohh I hate to confess this here. Remeber to put the spark plug back in and tight. I rode around the block with the plug 1/2 way in. I guess it was sucking air, cause it sure wouldn't start.
  13. decompiler

    decompiler Member

    Well, in the process of trying to take a couple of links out of the chain, I meesed my chain up. So I'm going to have to order a new chain. Until then I just wanted to thank everyone for their help.

    If I smoked, this is the point where I would go for a smoke break for about two weeks while I wait for the chain to come in the mail.
  14. decompiler

    decompiler Member

    Well, I almost had the whole thing working right for one fulll second.

    I cut about an inch off the clutch wire to give the arm some torque. Tightened everything down and gave the clutch lever a few squeezes. And Praise Be! - it actually looks like it was working right!

    Then the little keeper piece goes flying off. Goes ricocheting down the road. The wire comes undone. And the ends are freyed so badly that I'm just going to have to take the thing to a bike shop so THEY can deal with it.

    I followed the most low tech advice most people have here when it comes to clutch problems. Just take the spark plug out and ride it for a bit to get the stupid clutch loosened up. I did that and when the clutch wire was working properly for a single second, my bike actually worked.

    Oh well. Still, thanks for the advice all.

    Last edited: Apr 26, 2008