no spark 125m

[mudfreak99]

I recently changed out my complete bottom end, the engine was running before one of the center cases busted. I got it all back together, and I have a very weak spark. I pulled the coil and tested on a coil tester, spark would jump about 4 mm. But I don't know where to look next, also the electric start will not work, it will if you cross the solinoid with a screw driver, but not at the button. do these bikes have to have a good batry to run properly?

[dads]

If the spark is blue its good if yellow weak. check for power and ground at the soliniod connector to start button. if power and ground bad soliniod. if no power check start button connector under head light for power.
you can start one with jumper cables from car with out a batt. in it.

[Brakejob]

I have an '84 125m with no battery! Your spark does not come from the battery. As for the starter, bad switch, connection, 'noid. Just test for that as described in the previous post. DONE!