wheel wont spin

GoldenMotor.com
Jan 12, 2015
125
0
16
Merced, California
ok so heres some readings with a higher quality meter
magneto
1)between black and white= 1.1 million ohms
2)between blue and white= 470 ohms
3)between black and blue= 400 thousand ohms
cdi
1)+on blue - on black= infinite
2)+ on black - on blue= 176 thousand ohms
3)+ on spark plug wire - on blue= 12.6 million ohms
4)+ on spark plug wire - on black= 1.5 million ohms
5)- on spark plug wire + on blue= infinite
6)- on spark plug wire + on black= 1.05 million ohms
 

brown

Member
Feb 1, 2013
239
16
18
Bloomington IL
The reading you are getting between the black wire and the blue wire suggest to me the coil is fine. Even though some of the other readings you got don't make sense or seem possible.

Could you post a picture of your magneto coil with the magneto cover removed?
 

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
I believe what Brown wanted to see was the position of the magneto rotor and how it is indexed to the crankshaft. He wanted to make sure the rotor had not slipped or been installed incorrectly on the crank. Show us the magneto side of the engine, cover removed and put a little more light on it for us.

Be careful when you reinstall the coil. It is designed to go on one way. Also you'll want to space it away from the rotor while tightening the screws. You can insert a business card between the coil and the rotor to keep the gap open while you tighten it. You don't want the rotor to hit the coil when the crankshaft is rotated.

Tom
 

brown

Member
Feb 1, 2013
239
16
18
Bloomington IL
I wanted to see what vintage of coil you had. To me that is the older version of magneto coil. Hey for what it cost maybe you should buy the newer version of magneto.

Since you live in California if you look at Ebay and find a supplier who also in California you could have it only a few days. You can also buy them on Ebay.

However I am not convinced your coil is bad given your readings. I would be interested to hear how you checked for spark. Many time people are fooled about the motor having spark. When you checked for spark did you try another sprk plug by any chance?
 

brown

Member
Feb 1, 2013
239
16
18
Bloomington IL
No matter what a NGK B6HS would be a nice upgrade to what you have now. Pick one up at the Auto Parts Store and try checking your spark again.

When you do check try to do it inside or in a shaded area. The spark can be hard to see in direct sunlight.
 

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
I agree with Brown. I'm not convinced you have a magneto coil problem based on your readings. Like Brown, I can't tell much from the CDI measurements. Those are nebulous.

You need to take my advice about installing the coil. It appears from your photo that it isn't centered between the rotor. Looks like it might be touching on the bottom and has a larger gap at the top.

Try a new spark plug as he suggested too.
Going to bed now. Be back tomorrow.

Tom
 

fatdaddy

New Member
May 4, 2011
1,516
4
0
San Jose, Ca.
And hold the outer metal part of the plug FIRMLY against the head for ground, If the engine is painted, scratch off paint where you can hold the plug against it. Dont touch the electrode to it, just the place where the wrench goes. I usually have a friend hold the plug cause I REALLY, REALLY HATE getting bit by a jolt of spark plug fire.LOLzpt

And tom is right about centering the coil on the magneto, Looks like its gonna scrape where you have it set now. ya gotta leave a space on both sides. NGKB6HS plug
 
Last edited:
Jan 12, 2015
125
0
16
Merced, California
is there a way to check to see if a spark plug works without it being connected to the bike in any way? cause its not firing and its not the magneto thats doing it. so its either the cdi or the plug itself right? can i check to see if the spark plug works without relying on the cdi is what im trying to say
 

maniac57

Old, Fat, and still faster than you
Oct 8, 2011
4,484
22
0
memphis Tn
Try it in another engine you know runs.
You can also simply remove the cap from the wire and see if it sparks without the plug...
Remember, it's almost always the coil when chinadolls refuse to spark, CDI's rarely fail.
 

brown

Member
Feb 1, 2013
239
16
18
Bloomington IL
No. We you could check it on another engine. Did you pick up a new spark plug yet? I can walk you you through checking for spark if you would like.
 

fatdaddy

New Member
May 4, 2011
1,516
4
0
San Jose, Ca.
Try it in another engine you know runs.
You can also simply remove the cap from the wire and see if it sparks without the plug...
Remember, it's almost always the coil when chinadolls refuse to spark, CDI's rarely fail.
I agree 100% maniac, and he could Try it in his car or somthing, Same thing, plug it into the boot and hold it on a metal part of the engine. If yer not getting spark. IT'S ALMOST ALWAYS THE COIL. I've seen maybe 3 bad CDI's in my more than 10 years of building over 100 bikes.And working on HUNDREDS of customer bikes. maniac is probably right. Like I've been saying for most of this thread. It's prolly the coil.
fatdaddy.
 
Jan 12, 2015
125
0
16
Merced, California
but brown and tom say the readings i got from the meter about the coil say that the coil is fine. also i dont have a car or other motor around.... thats why i want this one so bad. otherwise i have to pedal anywhere i want to go. or take the bus. the bus is aweful...
 
Jan 12, 2015
125
0
16
Merced, California
WOOOH!!!! i tried testing it for spark and i couldnt see any but its pretty bright out so i decided to try to start up the engine anyway and sure enough it started! my idle is up really high though but i'll work on that