What octane fuel is considered the best I was running 91 non ethenol read that it was designed for 87 so began to use 87 non ethenol but find at lower rpm’s it wants to knock
Disclaimer: Don't believe what anyone including me says unless you have documented engineering proof.Are you getting knocking when under load at the low rpm and can't downshift into a lower gear? This time of year you can easily get "bad gas" that may have condensation/water in it. Oddly enough to combat water in the gas another alcohol additive like HEET is sometimes used (methanol).
You might try getting you gas at a different station. My son used to put premium in his bike until I convinced him it wasn't necessary or recommended by Kawasaki. These engines were designed for 87 octane.
I routinely add Seafoam to my tank every three or four time as it helps keep it running better. Check your spark plugs (condition, age and correct heat range) and consider checking/modifying the pickup coil gap. The compression on these engines is not high enough to require premium fuel and around here in California I don't think I can buy gas without ethanol in it, at least 10%. My bike doesn't knock (knock on wood). Knocking on a motor like the 750 with 4 valves per cylinder is usually related to carbon build up, weak spark, timing or in my experience bad gas. (Although perhaps a lean condition caused by a dirty or gummed up carb may add to the problem.) Seafoam and Techron additives may be your friend, I swear by them especially this time of year.
I had never heard that higher octane gas could cause carbon buildup. I will need to look into that as I am always learning new things. (Or forgetting things I once knew, I don't remember which.)
Well I've been doing it all wrong. I started using mid grade gas a few days ago and noticed it has ran better I thought it was in my head though. Thank you for the information on this.Since higher octane burns slower and cooler, it will create carbon in our engines, or any engine not designed for it. Along with slower starts, reduced power, and lower mpg.