Obviously the Harley swing axles has adjustment nuts for correct tension and centring the wheel, there are plenty pf video's on line for Harley rear wheels and belt removal/replacement to view.
For checking that a Harley Kevlar belt is correctly tensioned you use one of these tools, whether they are also appropriate for M3W I'm not sure [img]
https://www.ebay.co.uk/i/1723014360...msclkid=51a52b4be7c61a16e55474e82b7351aa[/img]
regards