Hey guys. Long time reader. FIrst time poster. I have searched and cant quite find the answer to my issue.
I have a 80 KZ750G that I bought in a non running condition. Automatically rebuilt the carbs using the Keyster carb kit (installed needle into 2nd from top notch) and rebuilt the petcock with proper seals and packings. Also installed inline pancake filters with mesh screens. I filled the tank with non-ethanol fuel. The bike cranked and ran fantastically well. It ran so good that I rode it from where I was working on it to my house (18 miles, ~50 MPH) and it never had a hiccup. Good acceleration, idled well.
So the next day, I decided to ride it on a short ride to church. It cranked and ran as before. However it started puttering like I was running out of gas and I couldnt hear any gas sloshing so I stopped at a gas station and put a gallon in. I only put a gallon in because it was E10 fuel and I was planning on filling it with E0 fuel later in the day. Pretty much immediately, the bike lost all power. It will run at idle fine, but around 3.5-4k RPM it begins backfires terribly. So my first though is junk gas. So I drained the tank and filled it back up with E0. I have let it run for several minutes in hopes that it will clear up and it hasnt. Symptoms now are currently:
-kick starts and idles fantastic ~1500 RPM
-With tiny amounts of throttle applied, engine speed will accel with no backfire
-Around 3.5-4k, engine speed begins to bog and will begin to backfire
My confusion comes in because it ran so well the first day and then went kaput.
1. So this sounds to me like the AFR is leaning out as the needle begins to lift? Maybe move the needles up a notch or 2?
2. I have read about timing being off maybe?
ANY HELP IS VERY APPRECIATED! TIA!
