sym mio 50cc spark issue. By housedadtrains (Read 616 times)

[housedadtrains]

Hi guys. new here so sorry if in wrong section.my problem is ive a sym mio 50cc. it has had new cdi aftermarket reg/rec resistors coil plug. now the thing is it will start and run of the kickstart as long as the battery is disconected. if you connect the battery which charges of the bike ok, the scooter will die. also when you crank the scooter it wont start as you lose the spark.. 

When the scooter is running lights everything works. if you put a bulb across the battery wires it still runs but not with the battery connected. Also if you take a charge voltage reading when the scooter is running it is only 7.5v?

I was wondering if the stator was dying or the battery? When it is running if you put the lights etc on it goes to stall but dosent..

any help appreciated..So in a nutshell it will start and run via kickstart but wont if the battery is connected.

[Alleyoop]

When you say it won't start when the battery is connected DO YOU mean that it will NOT SPIN THE STARTER??

Test the battery without the scooter running just sitting there and tell us what the mulit meter says the volts are?

It could be a bad stator, bad Regulator/Rectifier, bad Battery.

So first test the battery to see if reads bad or good.
Have you checked the GROUND WIRE on the Negative Post of the battery to make sure it is GROUNDED good to the frame?
Alleyoop

[cyborg]

Alley ,,,only 7.5 volts across the battery leads while it's running with them disconnected ,,,not enough to charge battery,,,,,,i would think 13-15 to be what it should be no??

[cyborg]

i agree with the insufficient ground,,,especially if the readings vary while it's running

[rob63]

I suspect the battery is shorting the system out, have you got a mate`s battery you could borrow just to check ?