weak spark
 

Ok I have a SpiderBox I picked up for $100 got it home put a new batt in it and fired right up ran like a striped ape. Next day nothing turns over strong but weak yellow spark any way to trck down what the problem is? oh yea it back fired through the carb.

Thanks for any help

Check the plug and connections to the coil. Could also be in the CDI, Stator , or pickup. Check the plug and coil wires first then check that no connectors or wires are loose, or corroded.