Motorcycle Repair: no spark, point gap, rusty surface


Question
i have an sl70 and i hooked my brand new spark plug up and spaced it right but it wont spark.

Answer
John, Check to be sure that the KILL switch is not in the OFF position......

If the ignition switch has a key, then be sure that it is also in the ON position. If the switch doesn't have a key, then just disconnect the ignition switch from the harness and test again.

More than likely, the ignition points, located inside the flywheel are corroded or out of adjustment. You need to remove the left side cover over the flywheel/generator and look inside the slotted holes to observe if the points are just opening when the flywheel F mark is aligned with the mark on the case. IF not, adjust the point gap to a more opened position and check again. If the points are not bright and shiny on the contact faces, they will need to be sanded with some fine wet-dry sandpaper or a point file, then cleaned off so no grit or filings are caught between the closed contacts. Once clean, check the gap/timing as described earlier. If you don't have spark, you may have a bad condenser, which will require buying a flywheel removal tool, unsoldering the old condenser and installing a new one. If it comes to that, buy a new set of points at the same time and put it all in new. Clean the magnets on the inside of the flywheel, too as a rusty surface will reduce the magnetism required to make a good spark at the coil.
The spark plug cap should be checked out, too, to see if it has an open circuit or if the resistance is much above 5k ohms.

Check this site for more info, too
http://oldmanhonda.com/MC/Rtiming.html

Bill Silver