Since the bike has been running poorly I decided no harm in checking the valve shim clearance. Turns out everything was under spec and I actually had to borrow a 2.45mm shim and move it to 5 of the valves just to get a reading. I've now got all of the valves adjusted with clearances where I can either fit a 0.076 or 0.102mm feeler between each cam lobe, I think one just barely allows a 0.127 when at the proper position.
The last few times I've performed a bench sync on the carbs and then thrown it on the bike I've gotten it to fire up right away. This time, however, I haven't been able to get it to fire. I noticed there is a significant difference in how the engine cranks now with the choke fully on vs off. You can actually hear the difference. Really seems to be pulling air through a lot better than before. I can hear a difference out the exhaust pipes too when just cranking. I plugged in the Carbtune to take a look and there's a marked difference between choke and no choke on there as well. There's no boot leaks as they're all new. Bench sync was done and I've got nice spark on all 4 plugs. Just doesn't seem to want to fire.
I might try some quick start to see if that'll get it running and hopefully prime all the vacuum tubes but usually by this time I've at least had a cough out of it. (And before you ask, yes, carbs have been dipped twice this year with new o-rings. Floats triple checked, new OEM Suzuki petcock and everything else on the "my bike is running like a sack of crap" checklist. All but the final piece which was the valve shim adjust. It was running good at higher rpm till this point but struggled at low end and 2-3K).
Hope I can get some ideas and get back to it after work tomorrow.
Thanks
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