Hi everyone, iv had my XTR stall on me a few times in random conditions

1, when its cold....i can understand that one tho
2, when i have been pulling away on a junction, before i have even got to the biting point on the clutch it has chucked out.
3, when im decelerating and going down the gears, it will sometimes just cut out

any help would me much appretiated!!!!