Splendor Plus i3s BS6 (11 months old): self-start fails when engine is warm, kick starts instantly
Splendor Plus i3s BS6 (11 months old): self-start fails when engine is warm, kick starts instantly
Bike: Hero Splendor Plus i3s BS6 (FI), Oct 2025 model, drum brakes, ~11 months old. I ride very little (some days 0 km, sometimes 3 km, sometimes 20 km).
Problem:
- Cold engine: self-start works on the first press.
- After riding for a while and stopping, self-start sometimes does not work. If I leave the bike for 10-20 minutes, it starts again.
- When it fails, the starter motor still turns, but slowly. If I keep holding the button for 1-2 minutes, the bike eventually starts with a struggle.
- Kick start always works instantly, even when self fails.
What I checked:
- Spark plug looks normal (light tan tip, a little dry carbon). Gap about 0.8 mm.
- I have not measured battery voltage or cranking voltage yet.
What the Hero service centre said: it is because of low usage (battery not charging fully).
Questions:
Does this sound like a weak or undercharged battery, or could it be the starter motor, starter clutch or relay?
Has anyone seen the same on an i3s? What fixed it?
Will a 60-70 km ride help? Is a trickle charger worth it?
What cranking voltage should I expect on a healthy battery?