I have a 1993 suzuki intruder 800, at times it would shut off (like turning off the ignition switch), the switch has just been replaced, all terminals to & from switch has been cleaned & secured. I even did the wiggle test at all wiring harness. The battery is new too. This only happens maybe once in 7 rides about 7 miles, or 10-15 minutes of driving time. Once restarted bike runs great.
1993 Suzuki gl800 intruder 800
changed battery, ing. switch, wiggle test wiring harness while bike was running(no problems found)
Try replacing the side stand switch. These have a high failure rate and are cheap and easy to replace. Part #15 on the link below.
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