no spark! ahhhhhhh

Discussion in '2-Stroke Engines' started by road_motor, Feb 2, 2008.

  1. road_motor

    road_motor New Member


    just finnished building my bike, was very excited to start riding, go down the first hill and engage the motor.......... and it doesn't fire! using the suggested 16:1 ratio for run in.

    took the plug out and turned the motor over, as far as i can tell there is no spark!! do you think this could be a faulty CDI unit? I have all the wires color coded, and even with the kill disconected still didnt fire. Im using the 44cc chinese motor by the way.

    can someone give me some advice, please??


  2. fetor56

    fetor56 Guest

    Give me a call(82404091) and we'll try to thrash it out.
    If i'm not there when u call leave a message and i'll get back to ya.
  3. Skyliner70cc

    Skyliner70cc Active Member

    I have had a CDI unit fail before but its possible that its a wiring issuew with the magneto...chinese aren't known for their good soldering of wires to wire posts.
  4. road_motor

    road_motor New Member

    ok a quick update

    did some readings on the multimeter, and were as follows;

    1. between black wire and spark plug clip was 2.3 ohm
    2. the blue to black wire on the magneto is 352 ohm (is this a little high?)
    3. between the black wire coming out of the mag section and engine "Ground" or block, near the spark plug hole was 0.8 ohms. seems ok.

    4. between white wire and ground is 2.5 ohm.

    Time for me to send an email to Warren at Zbox and get his opinion.

    p.s. the soldering is dodge, but it looks like it's in functioning order so I'll leave it for now.
    Last edited: Feb 4, 2008
  5. fetor56

    fetor56 Guest

  6. Watcher05

    Watcher05 Member

    Oh yes, this is just what I went through.

    One of the first things that I did was adjust the gap on your plug (sounds simple but those chinese plugs seem to be finicky 0.25" to .030 - play around). If still no spark, remove cap and strip HT lead back to show bear copper wires and hook directly to your spark plug. When testing, make sure your pushing it at a reasonable pace in low lit area.

    Those readings you have are basically what I had and now my bike is going so keep persisting. :)
  7. fetor56

    fetor56 Guest

    Drop-kick your Chinese plug,it's inferior....i use NGK B-6L but there are others that work great....see Warren's website.
  8. will_start

    will_start Member


    I have had it confirmed (By Warren) that I fried my Magneto. (the coil).
    Parts on the way.

    I'm going to borrow the text as written by Road_motor.
    I think this is the best Multi-meter read test result I've come across
    so far on this site (I know there may be some, in some place I've not read)

    Test Results of my Fried Magneto.
    1. Between White and Black Wires 3.1 Ohm
    2. the blue to black wire on the magneto is Open Circuit, (my meter does not show zero, but a solid 1. in my multi-meter left side.)
    3. blue to white wires is open circuit.

    OK, anyone want to confirm that it has failed for correctness sake.

    bye for now,

  9. Watcher05

    Watcher05 Member

    But didn't you get a coil reading (black to blue) of 352ohm. I think I took mine on the multimeter on 2000 (I think) other wise I was getting that reading of 1. Don't want to confuse you but you'll soon find out when you get the new coil.

    Good luck!
  10. will_start

    will_start Member

    how best to explain...
    The resistance value I get from Blue to Black is the same as
    having the probes apart in the air. IE open circuit.

    I am really feeling the coil failed because there's a hole where the wires go in front of the motor that I didn't know should be filled with Silicone.

    I have silicone at the ready...


  11. road_motor

    road_motor New Member

    Hi guys! wow lots of responses for one afternoon!

    ok, so im going to re-install my Mag sometime today (im at work lol), and try to fire it up again. Was that the correct way to test the CDI? I cant remember where i saw in the book about 2.3 ohm, but I'm sure I saw it somewhere.

    Fetor, where abouts is the best place to get plugs? Sprint Auto's would probably be ok, they are close to home too. (Port Adelaide Area).

    Ok so, if it STILL doesn't fire, im just going to order new magneto and CDI. Even if my CDI is OK, at least I'll have a spare. I really need to get this running! :)

    Cheers guys. Update soon.
  12. davidsis

    davidsis Guest

    I had mine filled with silicon and it still failed garage kept. Take cover off dry as a bone. My multi test reading was .300 on the number two on the horseshoe, setting. Which means it failed. Oh, ya and I used a real gasket that I hand cut out of gasket material. When I install my new magnito I am going to not even have a kill switch just in case that has something to do with it.
  13. ...So how's that spark plug wire?
  14. road_motor

    road_motor New Member

    wire is fine - just had a play, it's been narrowed down to the CDI which is strange apparently. wish me luck for when it gets here :p
  15. will_start

    will_start Member


    i have a spare CDI, as my plug broke,
    believe it or not there's a spring in there and I saw it go ping,
    and never saw it again, even after a thorough search.
    Was like a fly on my

    anyhow best of luck with the mag,
    I awaiting mine too.

  16. Skyliner70cc

    Skyliner70cc Active Member

    Please tell me that you didn't buy a new CDI because the spark plug retaining clip popped off? All ya had to do was unscrew the wire and and replace it with a quality automative grade plug cable.
  17. will_start

    will_start Member

    yep I bought what I knew would fix it for $xx.
    I'm new to these kits but not to shopping for parts.

    in life,
    its easier to get the part you know will work, than dodgy something you made up as a substitute that will work for yourself.

    especially if you have no knowledge of the motor.

    I'm assuming you have a mechanical background,
    and know alot about motors.

    I know this is off topic but I learnt something recently,
    when people learn a new skill,
    they go through four stages of learning.

    1. unknowingly unskilled.
    2. knowingly unskilled
    3. knowingly skilled.
    4. unknowingly skilled.

    the legends of a skill make it look so easy
    as the advanced things to them become easy.

    my humble.


  18. Scottm

    Scottm Guest

    I wish there was a way to keep good threads up top. Had to go back to October to find this.

    Everyone before us has had the same problems and given us the solutions. I'll be the first to admit I don't now much and can't contribute too much. My bikes run because of what others have posted and figured out.
    Last edited by a moderator: Feb 6, 2008
  19. garydl63

    garydl63 Guest

    check the spade connectors between the magneto and the cdi unit.
  20. road_motor

    road_motor New Member

    Wow, i haven't logged in since January! thats sad.

    Just an update...... been going through alot lately, so haven't made time to tinker. But, there is a up side to this update, and thats i now have spark!! now just to get some fuel, and tidy a few last things up. Sweet!