Slow starting F80 Yamaha

[barrymorerman]

Hi
I have F80 Yamaha and is slow to start from cold.I have charged the battery and it takes a few minutes of cranking before it fires and then runs normally.It starts with less effort when warm but may take a few cranks to fire Any ideas to rectify this?
Thanks in advance

[boats.net]

Load test battery and cables. May need to remove and clean carbs and test prime start system.