I rode bike about 20 mile round trip no problems. Later in day I took bike out and it died about half mile up the road. The bike cranked but would not fire. Started to push it home, stopped to take a break pushed starter button and it fired up. A week later rode it about 25 miles stopped to eat dinner. After leaving restaurant rode about a mile and engine shut off. Tried restarting, just turned over. Every few minutes I tried to start. After about ten minutes it started and went about 5 miles on freeway it started missing for a couple seconds then died. Waited about a minute it restarted and drove about 1 mile to my exit, when merging on next road it shut off again. After waiting a minute it started and rode 5 miles home. Any ideas where to start testing. The bike is 1990 electra glide ultra.