Everyone is unique, including those who fall on the autism spectrum. I was trying to get the OP to be more specific about what issues are arising for them.
Parents of kids on the autism spectrum seem to think only about how their child is cursed. They seem convinced that their son/daughter will never have friends, never hold a job, never marry or have a family, and be dependent on them for the rest of their lives. While this may be true for some of the lower functioning auties, it's not true for the vast majority of Aspies or Auties.
I know several people who fall on the autism spectrum, including my friend, an aspie and very avid cyclist, and my father, a high functioning Kanner autie. Autism can be a blessing, if channeled. It's helped my father, a bio-engineer, in his research.
Both of them enjoy cycling and don't seem to have any issues riding a bike. I was simply asking the OP to include more details about what issues they are having.
As for autism vs. asperger's vs. PDD, they are seriously considering dropping all the different labels and calling everyone on the spectrum-Autistic.