I'm getting tired of this damn thing. Seems like all I have done is wrench on this thing and nothing has been happening. I have no idea why it won't start. I'm gonna break this down Barney style and maybe you guys can help me out. Symptoms Before any diagnosis or repair the bike would crank all day and never fire. When cranking I get 1 or 2 fires after every 4-5 revolutions with the bike on full choke with the fuel screw anywhere from .5 to 4 turns out. It is a regular rhythm. With half choke I get some random fires. No choke I get nothing. Some backfires thrown in with every settting. Full carb details below. Tried bump starting while playing with fuel screw and choke and still no running. I would get a fire every now and then. A few times it fired once or twice then locked the wheel. Compression When the bike first stopped running compression was low. A leakdown test showed 20% leakage and all the sound was coming from the crankcase. I use a Harbor Freight tester with the shitty percentage gauge replaced by a second 100psi gauge. I pulled the top end and all the rings were stuck firmly in the grooves. I had to break one to get it out. I sent the head off to SSW to get a rebuild. I reinstalled the same piston and cylinder with new rings, circlips, piston pin, and gaskets. Nothing looked out of the ordinary with the piston or the cylinder plating. Everything was double checked. The piston is installed with the dot on the exhaust side and the rings are rotated 120 degrees from each other. Head bolts torqued to spec. I confirmed valve lash is within spec and I triple checked the valve timing. Spark Nice blue spark from the brand new plug. Pickup and signal coil resistance and peak voltage are in spec. Ignition coil resistance is in spec. Kill switch bypassed. Key bypassed. Clutch and sidestand interlocks bypassed. Fuel/air Air filter is clean. Carb is seated firmly and properly in the boots. Fuel flow from the petcock is good. 3x3 mod done, full Muzzy exhaust with quiet core and spark arrestor. It's 80 degrees out and 100 feet above sea level. Stock Mikuni 36 carb. Keintech extended fuel screw. JD Jet kit Blue needle, clip on 4th position from top 25 Pilot 155 main I have adjusted the fuel screw from fully seated to 4 turns out. Idle speed not touched I mangled up my old carb trying to open it up for ultrasonic cleaning thanks to those soft brass screws. I bought this carb off a guy who removed it from a running bike and replaced it with an FCR. What Now? Tomorrow I will do a leakdown test, but I'm not sure what kind of numbers to expect from a cylinder that hasn't had a break in run. I will check anything and try anything that you guru types suggest (Noble, E.Marquez, Eddie, Craigo, etc). Or I am very close to setting up a camera, lighting the bike on fire, and slowly walking away while I wait for the gas tank to explode. I would not look at the explosion, of course.