Check the stator to make sure each ignition circuit wire is OPEN to ground (the case). The stator has two separate circuits in it. One for lighting and one for ignition.
Get a manual (download for cheap or free) and go through the step by step process making sure that each measurement is within specification (you have to look your bike up in the chart).
Do a wiggle test on all wires while your buddy (who you bought beer for) pulls the sled over and over and over while you check for spark)
Verify all connections are clean and tight - tighter than a ....then check them again.
On my 96 summit disconnection of all switches (kill switch, ignition/key switch, and tether) will allow it to start - the circuits need to be open. Grounding the circuit is what kills the stator spark.
On my 96 summit - I had intermittent spark issues that were compounding an improperly connected HAC vacuum line - a wiggle test finally proved that the wires going into the CDI (right where they enter) were causing the intermittent issue. Though the CDI wasn't that costly - I replaced all vacuum lines, fuel pump, fuel tank filter, fuel lines, which were not needed and very expensive (bought them at the stealer).