Section 1671. Access of motorcycles

No local authority may enact or enforce
  a  law  that  applies  only  to motorcycles and the principal purpose of
  which is to restrict the access of motorcycles to any highway or portion
  of a highway under the jurisdiction of  any  such  local  authority  for
  which  state funds have been utilized for planning, design, construction
  or maintenance. Provided, however, that nothing contained  herein  shall
  be  deemed to supersede the authority of any local authority to regulate
  traffic pursuant to the provisions of this title, or to regulate noise.