48cc 2 stroke bbr tuning. Test magneto while in?

noyo

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Hey I have a 2 stroke 48cc bbr tuning motor bicycle engine kit I ordered about 2 weeks ago. Day 5 of trying to get the first start. Running it back and forth to autozone while the bike is down. Do I have to pull out the magneto from the casing to get a good voltage reading? Or can I leave it?

as it is.
16862402999074492060631293203800.jpg
 
The red wire from your engine connects to blue wire from the CDI and the blacks to black. Easy Peasy!

Looks like you have coil wires connected together.
 
The red wire from your engine connects to blue wire from the CDI and the blacks to black. Easy Peasy!

Looks like you have coil wires connected together.
Wiring is the most confusing stuff when it doesn't run haha. Here's how I have it wired: (Sparks)


Won't idle or accelerate, I tilted the engine more flat, maybe rewired it, the float was too slanted possibly.

Testing voltage on magneto/cdi box pics.

Magneto disconnected as shown, was asking if it has to be disconnected to get a good reading?
 

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I see what you're trying to do now. Electrical has never been my strong suit, I just know enough to be dangerous.

But, clean the case with a little fine sandpaper before you put your coil back in.
 
If you want to test your cdi and magneto, Use the ohm's setting on your volt ohm meter

Ohm the magneto from the black and blue wire, 320-380 ohms is ideal, an open or dead short means a bad magneto if the wires are connected.

Ohm the CDI in the 10K-20K scale.
Red+ meter probe to CDI black wire.
Black- meter probe to the spark plug cap.
You should get about 6.9K ohms.

Looks like in your last picture you were testing the cdi wrong -- read the above carefully and try again.
 
If you want to test your cdi and magneto, Use the ohm's setting on your volt ohm meter

Ohm the magneto from the black and blue wire, 320-380 ohms is ideal, an open or dead short means a bad magneto if the wires are connected.

Ohm the CDI in the 10K-20K scale.
Red+ meter probe to CDI black wire.
Black- meter probe to the spark plug cap.
You should get about 6.9K ohms.

Looks like in your last picture you were testing the cdi wrong -- read the above carefully and try again.
Is this wired correctly? Got the throttle cable prongs black and blue coming into the cdi. Got the black and red magneto prongs coming into the cdi. Is the cdi inlets correct?
 

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If you want to test your cdi and magneto, Use the ohm's setting on your volt ohm meter

Ohm the magneto from the black and blue wire, 320-380 ohms is ideal, an open or dead short means a bad magneto if the wires are connected.

Ohm the CDI in the 10K-20K scale.
Red+ meter probe to CDI black wire.
Black- meter probe to the spark plug cap.
You should get about 6.9K ohms.

Looks like in your last picture you were testing the cdi wrong -- read the above carefully and try again.
Tested the cdi box. Went bad - getting it replaced. Without a first start. Does wiring these wrong make them defective? Or maybe it was a bad cdi box to begin with.
 
Tested the cdi box. Went bad - getting it replaced. Without a first start. Does wiring these wrong make them defective? Or maybe it was a bad cdi box to begin with.
My first engine came with a dead cdi. It happens
 
Tested the cdi box. Went bad - getting it replaced. Without a first start. Does wiring these wrong make them defective? Or maybe it was a bad cdi box to begin with.
Not sure but I would guess it bad to begin with.

While your waiting for your new cdi Before you put the magneto back on the motor I would use some sand paper on the back of it and get rid of any shellac or grease to give it a better ground to the motor hopefully increasing your spark. I would also check the solder joints on the wires while your there it would not hurt to add more solder if you got a decent solder gun.

EDIT: If you can get leaded electrical solder use that instead of the new environmentally friendly stuff, Don't use the plumbing stuff though.
 
Sent me a new cdi box after a voltage reading of (1)5.17 and (2)5.63. Sent out for a new one after reading the voltage should read in-between 6 and 8. The 5.17 reading was the most recent one sent to me. (Didn't even get a chance to put the thing on, tested it right away @ autozone.) Asking for another one now. Would a cdi box with a reading of 5.62 even start the bike? Attempted to start the bike about 30 times. No go. Couldn't even get a reading on the stock one. [All of them sent out a good spark though]
 

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