Green coolant should be changed in every two years. Red/pink/purple(newer cars use those) are 5 years.
Its because it gets bad and corrosive to engine parts after two years of usage.

I will put red car coolant when i get my engine fixed. It lasts over 5 years. Polar premium longlife 8.5€ for 5 litres.

And it doesnt matter if it is car vs motorcycle coolant cause engine cooling system is the same for both. You just pay more for "motorcycle" name on the bottle.