new build not getting compression?

Discussion in '2-Stroke Engines' started by todouble22, Sep 8, 2010.

  1. todouble22

    todouble22 New Member

    Hello Forum,
    I built my bike last week and rode it this weekend working fine. I replaced the spark plug cap and adjusted the idle speed so that it was running quite nicely. I went to run it again this week and now there is no compression or tension when i dont have the clutch lever pulled in. I adjusted it and played around with the flower screw so that it is getting some tension but my issue is that when I go to start it seems to try to turn over at a low revolution speed. I'll try to explain better.. I can walk it around and release the clutch lever and it will sputter and sound like it wants to kick over, but if I pedal and pop the clutch at say like 5 mph it does nothing? Is there a thread on here that someone can direct me to or an adjustment that you all may know of that I need to make to get my bike up and running again? I appreciate all of your assistance in advance. cant wait to get up and cruising again.

  2. todouble22

    todouble22 New Member

    bump.. please help? anything?? I read through some posts and looked over the float. it seems to be fine?
  3. give me vtec

    give me vtec Active Member

    Is it a clutch issue or compression issue???

    If it is a compression issue there will be oil @ the source of the leak.

    Is there any oil residue anywhere on your jug/head???

    If there is a bad gasket it will usually leak oil. These things leak oil any chance they get through any opening or crack, so... any leaked compression will have oil residue in it which will be deposited somewhere close to the leak.

    Having said that... did you tighten the spark plug and top 4 nuts down on the top of the head??? Due to chepo chinese parts and labor... they rattle loose sometimes. Be careful because if you tighten them down too much you can brake the bolt.

    I highly recommend going to and getting the upgraded head studs.... you can torque them down way tighter which gives you a better seal.

    these are for the 66cc engine...
    Last edited: Sep 8, 2010
  4. todouble22

    todouble22 New Member

    I dont have any oil leaks anywhere. All of the nuts on the top of the head are tight and the spark plug is as well. I'm quite puzzled about what the problem could be. This weekend when I was riding it was all good. A problem I have now is that when I dont even have the clutch lever in I can still pedal and push the bike around, before the clutch lever had to be pulled in order for me to pedal and I couldnt just simply push the bike around? Thank you for replying , give me vtec. any ideas? I'll double check all my nuts and bolts and ensure that it is all secure again as well
  5. give me vtec

    give me vtec Active Member

    sounds like your clutch arm is adjusted too tight and is not letting the clutch disc engage fully. It doesn't have to be pre tensioned... just take the slack out of the line so the cable is tight. While you are adjusting things... take the clutch cover off and make sure the little Phillips screw is tightened down all the way.

    Al.fisherman's clutch mod is a must have.... he asks for like $15 shipped, or you could make one yourself if you have a welder.
    Last edited: Sep 8, 2010
  6. AussieSteve

    AussieSteve Active Member

    Another possibility is that this is yet another case of a sheared woodruff key, either on the countershaft sprocket, the primary drive gear on the RHS of the crankshaft, or the clutch itself. If so, turning the back wheel with the side-covers removed should quickly show which has sheared.
  7. HeadSmess

    HeadSmess Well-Known Member

    my money is on this one as well.

    been there, done that. at least it wasnt my bike, and to make it even better...i wasnt riding it :)

    it can be a lil $)*#$) to get the key in properly.... stupid woodrufs. gimme a straight key any day.
  8. Al.Fisherman

    Al.Fisherman Active Member

    When replacing woodruff keys, super glue them in place before assembly, especially where the magnet is concerned.