Jackshafted bike clutch wont engage

Discussion in 'General Questions' started by dui.solved, Mar 4, 2015.

  1. dui.solved

    dui.solved New Member

    Hey guys, I am building a Micargi Rover GT with an ebay 66cc stock kit and an ebay 119.00 china jackshaft kit. I know the kits not the greatest but im trying to make it work. The kit i got had 4 mounting plates, one of the four is just a chain gaurd. This is my second build with these kits but I am pretty good with mechanical things.

    The problem I am having is that when the clutch is engaged and locked, even if I push the clutch arm in with my finger, the crank cannot turn the jackshaft. I dont have the drive chain to the rear wheel on so it should just spin fairly easily when the clutch is engaged but it doesnt. I know that the crank and bearings are functioning so the clutch has to be the problem. I took off the clutch cover, removed the flower nut, the plate and spring. I cleaned out all of the friction pads (They are made out of rubber that looks and feels like pencil eraser) anyways i removed the exess and cleaned the area up, broke loose the clutch plate floating guides and greased the bearings and gears. I read about an issue with the grease drys and binds this process and this seemed to be my issue because it was pretty stuck when I first did this. At this point in the process the floating guides were still not moving freely but they did move with minimal force. So I reassembled the clutch, adjusted the flower nut a quarter turn out from the stock position and tested the lift. It seems to lift about 1/8 inch, maybe a little more, when engaged. I put the cover back on. Reassembled the engine, soft mounted it to the bike with a mock front mount, because its so far from the motor im going to have to make one that fits. Anyways, i just want the engine and jackshaft to turn. I know the jackshaft to pedal crank chain is loose but it should not affect the crank from turning. I have tried adjusting the clutch lever and i know that it is engaging there is no slack in the line. Please help, I am out of options here.

    I know its pointless to put a jackshaft on a single speed bike, but aesthetically its perfect. Here are some picks of the jackshaft and how its set up. 20150302_214303_resized.jpg 20150304_192608_resized.jpg 20150304_192424_resized.jpg 20150304_192342_resized.jpg 20150304_192313_resized.jpg 20150304_192302_resized.jpg 20150304_192235_resized.jpg 20150304_192156_resized.jpg 20150302_214530_resized.jpg 20150302_214430_resized.jpg 20150304_192638_resized.jpg

  2. KCvale

    KCvale Motorized Bicycle Vendor

    Check your left side clutch cover gear, chances are your 415 chain is binding on the left side of the cover plate.
    Just grind it out or cut that end off, you don't need it and the mag cover covers there anyway.
  3. dui.solved

    dui.solved New Member

    the chain is binding. I am filing down the rub area and hopefully not having to remove it completely. It is rubbing because the angle of the jackshaft sprocket to motor output sprocket. 20150305_011724_resized.jpg 20150305_011756_resized.jpg
  4. dui.solved

    dui.solved New Member

    thanks for the advice hopefully that works, ill post pics when im done.
  5. KCvale

    KCvale Motorized Bicycle Vendor

    No problem, glad I could help.
  6. dui.solved

    dui.solved New Member

    I got it all on and set up. Pedals fine with the clutch engaged, put gas in it and went to start for the first time....nothing. When I dump the clutch the motor isnt turning. I know that with a jackshaft I have to keep pedaling to turn the motor but its barely even harder to pedal with the clutch out. I did loosen the flower nut 1/4 turn when i had the clutch open. Did that do too much? Please help.
  7. dui.solved

    dui.solved New Member

    got it started. Tightened the flower nut back to original position. Seems too tight but maybe im just not used to the pressure needed to turn the motor over. Anyways i re-assembled, rode and when i dropped the clutch it stuck but when i gave it a good kick it turned and fired up on the first go. The jackshaft chain is super loose but not loose enough to remove another link and i cant adjust it....thinking of a half link.
  8. KCvale

    KCvale Motorized Bicycle Vendor

    Just pedal up to good coast in 1st, get your right pedal to about 1 O'clock, let out the clutch, stand up and kick it down like you would a kick start on a motorcycle and pedal through.

    Both chain will loosen up real quick when new.

    Easy enough to check if a 1/2 link will help, just take out the master and pull it to see.
    Why can't you adjust it?
    Got a picture of the right side drive?
  9. dui.solved

    dui.solved New Member

  10. dui.solved

    dui.solved New Member

    The last three pics are of the chain after the first start and 2 minute ride...the chain went crazy loose and came off. I tried to attach the stock chain tensioner, it works well and it helped to keep the chain from rubbing the bottom bolt of the engine case, but the chain just stretched. The right side jackshaft sprocket does not have any way to adjust it to take out that slack. I went and got some half links. I found some at my local bike shop that were "heavy duty" they dont have pins that hold them together, the connector is pressed in with the chain breaker. I am going to remove the master and see if its loose enough to just remove another whole link, I dont think it is but ill check. I should point out that the left side (engine output to jackshaft) chain is the 415 chain that came with the motor kit. The right side (jackshaft to crank) chain is a 410 chain that I got from the bike shop for $10. The 415 chain and the chain that came with the jackshaft kit did not fit the 10 tooth sprocket, the 410 from the bike shop fits nice. The right side chain (crank to rear wheel) is the stock bike chain with a good master link on it. I Started the bike and rode it, let it idle for maybe 2 minutes before the chain stretched to the point that it is in the last picture. Both of the chains on the right side stretched, the 415 motor output chain did not stretch at all.
  11. darwin

    darwin Well-Known Member

    A chain should never have more than 1/2 an inch play in the center of its bridge.
  12. KCvale

    KCvale Motorized Bicycle Vendor

    If you want peoples help, PLEASE break up your text with open space between sentences so it can be easily read.
    Thanks ;-}

    You only have one mount point on the tensioner, that won't hold.
    That is not your problem however...

    It looks to me like you took every time and penny saving shortcut you could think of and expected it to be as good as the real thing.
    Transferring ~3HP in bi-directional rotational force is not to be trifled with.

    The bottom line here is you bought a crap knock-off jackshaft kit that will give you grief forever.
    I don't even see the support bar under the JS mount for adjusting that right side chain tension.

    Did that kit even come with the underside support or instructions you read?

    Yes it does, by moving the whole engine assembly up or a tensioner wheel somewhere, and you have room, you make up the difference with spacers on the front mount and let that support help on the back.

    Correct, take out a whole link and just press the 1/2 link on to the remaining small chain end.
    NOTE: orient the 1/2 link small end that goes to the master in the direction of chain travel.

    It will, and that is even harder to adjust, especially with that 3 piece base, you need to shim the engine away from the base.