Hi! I have an issue with my chinese atv (brand unknown), its a 110cc 4stroke engine. The problem is that it is possible to roll start the engine and everything then works fine but i cant start the engine via start motor. The start motor goes around when pressing startbutton but the sparkplug doesnt spark.
And im just wondering if someone have had same issue with their own atv and managed to fix it?

Thank you in forehand!

 

Does the engine go round when the starter is turning? If not the starter clutch has failed. A very simple thing on that engine. 3 rollers with springs behind them forming a one way clutch for the starter to drive the flywheel. Usually the springs, which are Chinesium, fail and don't push the rollers out. Other possibility is the starter chain has broken.

 

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​​​​​​The engine goes around when using the starter. But there is no action on the sparkplug.

 

It depends on if your ignition is AC or DC what the problem could be, with DC ignition, when you turn the engine on the starter, the voltage from the battery drops, so it is more difficult for the ignition components to produce a spark. Many have an extra wire from the neutral light so, when in neutral, the CDI produces a more powerful spark to compensate for this. With AC ignition, in theory, the ignition system is completely separate from the battery system, like a magneto, so this problem shouldn't occur. However it is just possible an earth problem may cause trouble.

 

It's DC system and I have powered it with my car so that could not be the issue :/

 

Problems with the DC ignition system are not due to a low battery. The "only sparks when I take my finger off the start button" problem comes up on here regularly and nobody seems to give an answer. Some recon it is a trigger coil problem. As I wrote above, if it has a neutral, and has a wire from neutral light to CDI/ignitor box, this can come off or break and give this symptom.

 

Run a direct wire from the battery to the CDI power connection. I think it's pin 6. Problem solved.