My very quick guess would be a TORS issue. There's a switch in the throttle mechanism at the handlebar which should trigger when you thumb the throttle. The pivot point should move when you apply pressure, tripping the switch before it actually starts pulling the cable. If the switch doesn't trip, the engine management system thinks the cable is jammed open and prevents the engine revving fast enough to activate the primary clutch; it does this by cutting the spark. Make sure the throttle cable is adjusted with some slack in it (check the book or a Yamaha forum). There's a way to by-pass the switch, but most advise against that except in a test scenario.
Last edited by RogerG; 02-15-2020 at 03:07 PM.
Reason: correcting a typo