Bike having some problems.

Chainlube

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Noticed that my spark is really weak at low rpm but kinda picks up once the bike starts to go quick. This might be my problem. The cdi I have I thought that it was really good and gave off solid spark? I have the bbr tuning stage 2 cdi.
How did you determine that?
 

Chainlube

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Took the spark plug out, pushed the bike and looked at the spark plug while it was against the engine.
Low rpms can cause a weak spark, the mag isn't turning fast enough to generate the power.

Did the key in the mag break? Is the mag put on the right way round?
 

darwin

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Low rpms can cause a weak spark, the mag isn't turning fast enough to generate the power.

Did the key in the mag break? Is the mag put on the right way round?
Dunno Chain, just pulling on the starter rope should put out a nice spark to start the motor. Pulling rope = low rpm's. Maybe you're right. Be a nice experiment to see.
 

DAMIEN1307

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Dunno Chain, just pulling on the starter rope should put out a nice spark to start the motor. Pulling rope = low rpm's. Maybe you're right. Be a nice experiment to see.
Did I miss something again???...I didn't read anywhere that this was a pull start but did read where it was a pedal bump start.
 

Nickt919

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Have 3 none work
That is a bit odd unless there’s some condition shorting them to the point of killing it.
I have found the weak spot on a stock cdi is inside the spark plug cap. They sometimes lose continuity inside the cap.
It’s a good idea to change the stock wire AND cap out for something a little better.
 

darwin

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Did I miss something again???...I didn't read anywhere that this was a pull start but did read where it was a pedal bump start.
Pull start/bump start = low rpm starting in my book. I think even at slow rev the spark should be strong to start the motor. Just my thinking.
 

Chainlube

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Pull start/bump start = low rpm starting in my book. I think even at slow rev the spark should be strong to start the motor. Just my thinking.
Oh, you're absolutely right, but rolling a bike or turning the wheel and watching for spark is a hard task. That's why I have a rear wheel stand, so I can spin it with a little velocity.
BTW I've had a couple of coils quit on me but never a CDI.
 
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