Have just completed a fabulous 850km (530 mile) return trip from Perth to the SW of Western Australia to celebrate 50 years of the CB750. My mate was riding my 500 (I was riding his 750K1) and it had no trouble keeping pace with the 22 750s....until late yesterday.
Roland (my mate) reported that it had instantaneously dropped to 2 cylinders for about 3 or 4 km and then straight back to 4.
When we arrived at our stay for the night we did some initial troubleshooting. We were able to determine that cyl 1 and 4 went missing.
After removing the tank, we checked the connections to the coil in question but nothing was found.
Anyway, on the way home today it intermittently dropped 1 and 4 again and progressively got worse. Roland managed to limp it home on variously 2 and 4 cyls. No fluttering/fluffing, just straight to 2, then straight back to 4.
Tomorrow we plan to do more thorough troubleshooting to hopefully identify the problem. The initial plan is to double check ALL connections and possible intermittent wire-shorts from the Dyna-S to the coils. If that doesn't reveal anything, then we'll swap the coils over and see what that reveals. If nothing again, then we may have to suspect the Dyna-S, which BTW has been running without issue since I 1st bought the bike, until this w/end.
For those with experience, does this sound like a good approach? Are there any other things that we may need to look at?
Fuel issues have been ruled out. (Someone recently remarked that 99% of fuel problems are electrical!
)
Cheers
Andy