My bike not self starting, but starter motor and kick starting works.

My guess is that the starter relay / solenoid or wiring / contacts are the primary suspect. The relay contacts might not make a good connection when cold (higher resistance), but after heating (or vibration) they make better contact. Also the wiring / grounds may have marginal connections.

So I’d start by checking / replacing the starter relay / solenoid, and cleaning all associated connections.

Here’s a recommended order and what you should measure / observe:

1. Check for spark when self-starting (cold)
   • Disconnect a spark plug lead, ground the plug to engine, try self-start, see if there is spark.
   • If no spark when cold (but maybe spark when hot), ignition is suspect.
2. Measure voltage during cranking
   • Use a multimeter: check battery voltage, and voltage at the ignition coil primary, or at spark plug lead, while pressing the start button.
   • Also measure voltage at the starter motor terminals and across the starter relay when you push start.
   • Look for big voltage drops (> 0.5–1 V) between battery and starter / ignition circuits.
3. Inspect / clean / replace starter relay / solenoid
   • Open the relay/solenoid and check the internal contacts for wear, pitting, or corrosion.
   • Clean or replace the relay if contacts look bad.
   • Sometimes bridging (jumpering) the relay temporarily is a diagnostic (bypass the relay) to see if that restores starting (only do this carefully, understanding the wiring).
4. Check wiring and ground connections
   • Especially engine-to-frame ground, battery negative to frame, all main cables in starter/ignition circuits.
   • Clean and tighten all connections.
   • Look for broken wires, corrosion, loose joints.
5. Test the safety switches
   • Clutch switch, neutral switch, kill switch: sometimes these switches fail intermittently.
   • Try bypassing them (or testing continuity) to see if starting works when they’re “forced on.”
6. Test the starter motor itself under load
   • Remove the starter, bench test with battery, see if it spins strongly at cold and warm.
   • Check brushes, commutator, windings.
7. Check ignition / CDI / coil / HT lead
   • Even though you replaced coil pack, the rest of the ignition chain (CDI, wiring, leads) may have marginal connections.
   • Under cold conditions, slightly higher resistance or marginal parts can fail.
8. Battery condition under load
   • Ensure battery is fully charged and healthy.
   • Measure how much voltage it sags during cranking.