Wiring Question

Discussion in 'Electrical' started by jimemarsden, Jul 17, 2014.

  1. jimemarsden

    jimemarsden New Member

    Hey guys!

    I'm new to the forums because I've just recently bought a second hand kit from a guy off craigslist (which was pretty sparse to say the least, lacking a feul line, filter, drive chain and many other things) and I'm having a TON of trouble figuring out the wiring. I have no idea why I'm having so much trouble, there are like six wires total. I've been following this diagram http://i685.photobucket.com/albums/vv219/OzzyU812/ElectricalDiagram.jpg and I've tried almost every combination I can think of. I've brought it to a couple of my dad's friends and my friends' dads but they don't know how to wire it (but they also don't have time for a "silly little bike". I know it's not the sparkplug because I've tried the one it came with and some new ones I bought with the 'touch it to grounded metal and spin the wheel' test. I'm pulling out my hair here - everything seems right! Can anyone shed some light on this? I am too eager to get on the bike, thank you to anyone who can help!


  2. HeadSmess

    HeadSmess Well-Known Member

    you have a big learning curve ahead by the sounds of it.

    wont it be fun to give the father and friends the finger once you have cleared the first hurdles?

    one. forget the kill switch for now.

    wait. i meant to say, before that, do a search but hey... i feel like repeating myself again... and seeing as you found a pic you must have searched somewhere.

    back to one...there, that leaves 4 wires, with no kill switch to worry about.

    meaning you have only two connections to make.

    got your multimeter handy?

    from engine, you should have two wires. colour is irrelevant for now.

    with the multimeter on ohms, you should get approx 300 ohms between the two wires.

    if there is a 3rd wire from the engine, and its white...CUT IT OFF! and its probably whats wrong anyway, and why the orig owner sold it... the white wire is known to fry the magneto. if there is no white, forget about it...

    now, test each wire against the engine itself.

    all being good, one will give the same reading as before, 300 ohms or so. it should be blue.

    the other will say no ohms, or direct contact/short circuit, or GOOD EARTH :)

    this is, obviously, what you WANT.

    if you had a reading between wires, but not between either wire and engine... remove magneto, sand the back of it, make sure there is metal to metal contact, replace, and repeat the test.

    so, you had 300 ohms between wires, and one is earthed. hopefully that ones black.

    now look at the coil, the lil black box attached to the spark plug.

    it also has two wires, one blue, one black...

    join black to black, blue to blue.

    check for spark!

    if there isnt any, theres a few more things to do.

    multimeter to AC VOLTS. (it has the ~ symbol) measure across wires from motor when spinning wheel. you should get a reading like 20v+

    if you do, the magneto is fine, and you need to buy a new CDI/coil, which is the lil black box.

    fit new parts if necessary, and you should get spark.

    and therefore at least a cough out of the dirty lil thing!

    then you just wire one of each wire from the kill switch to the blue and black wires. done.
  3. jimemarsden

    jimemarsden New Member

    Thanks for the help, looks like I need to go get a multimeter! I'm hoping that I can find magnetos and cdis at a local lawnmover store. And you're right, this has been quite the learning curve but I'm proud of myself for getting this far, and I did have it wired up correctly apparently, it's just one of those two and I just gotta find out which. Thanks!
  4. HeadSmess

    HeadSmess Well-Known Member

    no prob.

    if you had blue2blue black2black and no spark...

    check the earth on magneto. ie, take it off, sand it, yarda yarda. can see if its making power by hooking a 12v globe up to it without the multimeter. add a battery and you can check for continuity, etc. gotta think for yourself at times :( use what you can find...

    but more than likely its the magneto has fried. they do that... the cdi can fail but its not as common. still, they do have a finite life, being chinese, cheap and highly stressed in use!

    dont bother the mower shops, unless you want to be laughed at...or you get lucky and someone there has one in his shed anyway. never know. they do not share anything in common with any other engine. and having no part numbers is a real headache until you realise that these engines, and these engines alone all share basically the same parts. (only the case, piston and cylinder are the real differences)

    parts available online unless you know of a shop selling these engines already... which it appears you dont. online it is. fleabay. about 10-20 bucks.

    remember that any shop you take it to is only interested in making money to keep their doors open.

    the cdi can be made if you want to start really sinking your teeth into it. try google. "rohmell cdi". already posted it on here a few times... google is your friend :) its just knowing what to put in to the search bar ;)

    and this is only to get a spark, you have not even started on the other bits yet!

    have fun. learn. educate yourself. accumulate tools. ;)

    self sufficiency is a virtue.
  5. jimemarsden

    jimemarsden New Member

    Just checked fleabay, apparently visitors from my country are not allowed to visit the site! I bought a multimeter to test the stuff and the cdi got a pretty good reading and I got jack from the magneto, so that must be it! I tried looking around for the wire used but I completely forgot how delicate and how many times the wire needs to be wrapped, I thought I could make one myself. At least I know what to buy though! I just hate having to wait for it to be delivered, I want to ride it right now!! Thanks for the advice again, you've been a life saver.