Clutch Bike rolls freely with clutch lever open

Discussion in 'Transmission / Drivetrain' started by KellT, Jul 3, 2016.

  1. KellT

    KellT New Member

    Just to start- I did check the other site on adjusting the clutch and making sure everything is tight and that is fine- I do not believe this is a clutch issue.

    The problem- The bike was running fine today, although I first noticed an issue when starting it up, I would pedal, release the clutch, then nothing, it continued rolling as if I was holding the lever, I'd do this again and then it would start up and worked fine.


    PROBLEM- after adjusting the clutch so that i worked fine I found when pushing the bike with the clutch lever open that the bike would free wheel. I took the head off and clutch cover off and noticed the piston would move up and down but then stop as I continued pushing the bike foward. The clutch and the gear would not spin however the bike would continue to free wheel if i pushed it foward

    I guess something is happening where the drive sprocket is not driving the piston up and down and simply freewheeling.

    Also it seems the cover for drive sprocket is tightened on to a rediculous degree. Is anybody in the Lehigh Valley area of PA that can help?

    Is this engine toast? Or is it fixable?

    I ordered a new engine pair from BEKITs but this engine is only a month old, and I didnt ride it hard.
     

  2. bakaneko

    bakaneko Active Member

    when you say adjust the clutch, do you mean just adjusting the clutch cable? you probably need to open up the cover and tighten the flower nut.

     
  3. FurryOnTheInside

    FurryOnTheInside Active Member

    "the clutch (plate?) and the gear would not spin.."
    I don't think it is toast, my guess is you just need to remove the sprocket cover with an impact driver and check the status of the sprocket and it's cheap replaceable Woodruff key. :)
     
    Last edited: Jul 4, 2016
  4. KellT

    KellT New Member

    Thanks will check it out
     
  5. gary55

    gary55 Active Member

    Woodruff key is my guess too.
     
  6. FurryOnTheInside

    FurryOnTheInside Active Member

    Now I'm curious about why the key snapped. They're sacrificial, but they aren't supposed to break randomly, supposed to be strong enough to pull you up hills anyway and take the shock of bump starts..
     
  7. gary55

    gary55 Active Member

    It's a mystery. Some last beyond the engine life. Others fail before the brake pads wear out.A lot I have seen are caused by the gear retaining screw backing out. I have seen them fail when someone is haulin ass with a loose chain, and when it jumps a link and jams against the gear cover things go from 6500rpm to zero in a instant. I've seen the slot in the crank wobbled out. That should be pretty hard assed steel. I think we are just getting the quality in materials and craftsmanship that we have paid for steered by a little luck and chance.
     
  8. KellT

    KellT New Member

    Well I drive like an old granny, however there are alot of bumps and the bike doesnt have a suspension. I've also driven it offroad at about 10-15mph along a dirt stretch. I'm still waiting for my impact drive which is coming this next week and take a couple pics of the damage. The engine itself was one of the ebay specials but besides this problem, the motor runs like a champ. It probably has a total of 25miles on it. My guess is something was probably loose to begin with, and since I didnt have an impact driver, I couldn't tear the engine down to check.
     
  9. gary55

    gary55 Active Member

    Release clutch lever and look inside the cover where the chain goes in while pushing the bike forward. If the gear is spinning but the shaft that the nut is threaded to is not you have isolated your problem to the drive gear key. If the drive gear and shaft is spinning but the clutch plate behind the clutch gear is not spinning you have isolated the problem to the clutch assembly woodruff key, or broken clutch shaft. the later is unlikely. If the drive gear spins, the plate behind clutch spins, but the clutch gear won't spin it's pressure adjustment. If none of the above are the case it's the crank gear key.
     
    Last edited: Jul 12, 2016
  10. KellT

    KellT New Member


    Well I managed to get the cover off.

    [​IMG]

    [​IMG]

    I'm guessing its a bit of the inside of the cover got shredded by something. Sorry for the blurry pictures, my camera is a potato
     
  11. crassius

    crassius Well-Known Member

    those chain marks on cover usually mean that the sprocket has come loose - if so, then the key that locks it is gone or broken
     
  12. gary55

    gary55 Active Member

     
  13. gary55

    gary55 Active Member

    KellT I have to apologize for my trouble shooting described in reply 9. I updated it to be more accurate. I just noticed the error. Of course the drive gear is going to spin when the bike is pushed forward, It's hooked to the chain. The shaft would be stationary with a bad key at this location. Again sorry.
     
  14. KellT

    KellT New Member

    yup- the pin in the center of the drive sprocket comes out freely. I can replace the key, but I dunno why this happened in the first place which is kind of worrisome
     
  15. KellT

    KellT New Member

    Well ain't this a B.

    looks like a chunk of the shaft was gouged out either when the key broke or to begin with which is what caused the key to break.

    Hmmm..I guess I can use this for parts, or break out the welder and try drop a bead or bust out the jb weld and redneck it.

    What d'yall think? Again I apologize for my potato pictures. I might just invest in a camera from this decade.

    The slot on the left is the key slot

    [​IMG]
     
  16. gary55

    gary55 Active Member

    You can get a new clutch shaft assembly from Kings motorbikes for 14 bucks or just the shaft itself for 2.50 They are not that hard to replace. Probably need a new key and cover. Don't think the JB weld is the answer here. I guess if you where considering welding it you could tighten it back on with the nut then remove the nut and weld the gear to the shaft. Don't think that is the best idea either. Usually a lot of flammables in that area. Probably have to go slow so you don't melt the bearing seals and the grease in then. A lot could go wrong without proper prep. and it would be a bitch to burn your bike down for a 2.50 part.
     
  17. crassius

    crassius Well-Known Member

    look around the board and you'll see a lot of this same problem lately - some factory is failing to get these on tight

    this never used to be so common a problem

    what kit did you buy?
     
  18. KellT

    KellT New Member

    It was an ebay special. However I've since gotten a kit from BEKITS.com. It is SO good, i prolly will never buy any other type unless the quality starts dropping. This engine will be shelved for parts. It's a 38mm half breed per Fred's designations. I could get the premade clutch bar and put it in but I doubt it will perform anything like the bekits engine pk 80.
     
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