There is nothing that prevent a scooter from being build with larger wheels and a longer wheelbase. In fact that used to be how human powered scooters were buil

There is nothing that prevent a scooter from being build with larger wheels and a longer wheelbase. In fact that used to be how human powered scooters were built a few decades ago. It would not help the rider steer with his legs like a motorbike but this is at least what I would do if I was looking to break speed records.