I also had problems starting the bike. That happened after I had tampered with one of the slow jets. The gas pulses out of the left exhaust were weaker than those from the right one.

I had cleaned my jets but it is not until I renewed them (MJ & SJ) that the bike starts at 1st/2nd kick. Cleaning jets is not always a guarantee. I also changed the carb insulator and made sure it is correctly tightened and that the airbox rubber boots are airtight.
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