I need to replace the rear tyre on a R2J model the tyre size is 150/60/18, usaually for my other MC18 have always fitted Bridgestones BT090 however they appear to be discontinuted. What choices have people used on their MC18's?

I also read that you can fit a MC21 rear wheel straight in as its a direct fit. But what tyre size would you use? does it affect the ride height? or any performance issues?

Prop a silly question just looking for some solutions.