Scooterotica

When changing to a twenty toothed front sprocket on a sil gp200 do I need to get a stretched chain or add a link? The chain thats on it has done 4000 miles might it fit?

i've got a 20 tooth front and 46 rear. I've put a 83 link chain on with a Rocho down-push tensioner....fits fine and runs fine...

20X47 83 link

Thanks Lads