Constantly having to adjust clutch... WTF

Discussion in 'Transmission / Drivetrain' started by zanygirl, Oct 20, 2015.

  1. zanygirl

    zanygirl New Member


    Successfully fixed my throttle problem not too long ago, and my bike was running like a champ until a couple of weeks ago. I frequently have to adjust my clutch cable in order to get the durn thing to disengage (engage? I get them backwards, bear with me) completely. I have found that if left alone, my bike will be very difficult to pedal, or even walk... A bit like trying to start pedaling in a really gear, or if the rear brake is permanently engaged.

    At first, I figured that my clutch cable was stretching out and kept adjusting it. However, after roughly two weeks of this, my clutch arm had moved from the usual position (offset to plate covering sprocket) to underneath the carby.

    Pretty sure that there is something wrong in the clutch mechanism, but am not sure if it is a spring that has been jammed, something that bent, or something that needs re-greasing. Looked up some diagrams and started taking things apart this afternoon, but called it quits after I removed the sprocket and ring gear 1) couldn't manage to remove the rest of the clutch assembly; 2) figured I ought to do some more homework/ask questions before I accidentally FUBARed my bike.

    Anyway, thoughts on what may be causing the problem? I can try explain myself better if the above doesn't make much sense. Also, how the heck are you supposed to get the rest of the clutch assembly out? My research lead me to believe that after you've gotten the gear and sprocket out, you can just whang the rest out with a hammer. I tried this for a bit without any noticeable results.

  2. HeadSmess

    HeadSmess Well-Known Member

    probably the ball wearing out...

    you dont have to pull the sprocket.

    just the clutch cover arm thingy.

    the clutch arm itself ends in a rod with a flat on the end. that needs a dab of grease.

    that flat pushes a rod into the hollow shaft the sprocket runs on. pull out the bar... then a ball bearing about 8mm in diameter will fall out of the shaft.

    they usually crunch up and die due to lack of lube or just being cheap and nasty.

    pretty easy to get hold of one from a bearing shop... or a helpful mechanic can break an old ball bearing for you, give you a whole handful of them.

    the bar itself can wear out.. i personally use a length of tungsten carbide or HSS... machinists are always throwing away old endmills made of pretty hard stuff :) just need an 8mm one...or was it 6? iunno!

    it all needs a good lump of grease stuffed down the hole, along with ball and bar...

    otherwise, its the shoes themselves are wearing rapidly?...unusual...

    and last thought which should be the first thought really...

    under the clutch cover itself, the clutch is adjusted with this horrible thing called a flower nut. there should be a small screw inserted in the notched edges of this nut to stop it rotating... if it aint there, will keep going out of whack... just this tiny lil screw...
  3. zanygirl

    zanygirl New Member

    Boy do I feel smart! Well, at least now I know how to take it apart.

    Will have to take a look at the bike to know for sure, but I think that grease and a funky bearing might be it. When I took the sprocket plate off, the cam shaft slid right out, but the ball stayed in place. Considering the top notch quality of HT engines, it probably got mashed in or something.

    I have a bunch of old bearings from a bicycle restoration project a couple of years ago. I'd like to think that I could use one of them... Apart from diameter difference, it seems like bearings would be pretty similar as far how much stress they can handle, right?

    I saw the flower nut and the screw. I am curious about the screw... On my bike, there's just the one, but there's a hole for another screw as well... Second screw needed? My guess is that it isn't totally necessary, but nice to have all the same.

    Thanks for the suggestions! Will report back after I've dinked around some more
  4. Greg58

    Greg58 Member

    Check the clutch cable also, I've had a couple of the kit supplied cables fray and break. I learned to remove the cable from the housing and grease the entire length before installing it.
  5. Timbone

    Timbone Active Member

    Check the clutch cam, too. Those things can wear down quickly so it's good to have an extra around. There are several ways you can make them.
  6. HeadSmess

    HeadSmess Well-Known Member

    ball size isnt critical but it will affect the clutch action as the lil bar and the ball together make a specific length... the balls from a bottom bracket would probably be ideal. too big it wont fit, too small and you need two of them or a longer bar or something...

    correct, load rating is much the same, in much the same sizes... except for the quality/manufacturing process for which we can say zip... get something from an skf or a nitto and you cant go, hi quality bearings.

    clutch adjusting and the flower nut...the 2nd screw hole, if you check closely, wont line up with one of the notches in the flower nut when the other hole DOES. its pointless really, a smidgen of a turn either way makes nearly no difference. now if it was a locknut that needed to be held in place AND kept at a certain torque... it isnt. its just an adjuster. just needs to be kept in place.
  7. zanygirl

    zanygirl New Member

    Alrighty... Grease was just what the doc ordered (thanks, Greg & HeadSmess!) Also changed the cable and replaced the ball with one from a BB on my organ donor bike. All seems well except now the engine won't start. I release the clutch lever and I get nothing. No idling, no jerking motion, nothing. Will try adjusting the cable this weekend to see if I can get it to do anything.
  8. HeadSmess

    HeadSmess Well-Known Member

    bit of fiddling getting the setting of the cable and the setting of the clutchplate/flower nut just right.

    take tension off clutch with clutch arm, while adjusting the flower nut. then adjust the cable.