I have a very aggressive son who is 4ft 4inches tall and weighs 67 pounds. He is beating the death out of his XR70 and wants something with more suspension and lighter with a clutch. Some persons have suggested a stroke 65 or 80 and he has had time on a ktm 50 and did not like it besides how light it was. SO CAN I GET SOME INPUT ON WHAT ALTERNATIVES I HAVE? I really would like a light four stroke or some REAL advice on how to tame down a two stroke 85 without a ton of engine work ( flyweight changes because i am not that engine savy) I had a kdx200 back in the day and that type of power band would work!