UN R51 allows the use mechanical or electronic devices to control the gear shifting and measures to avoid accelerations greater than 2.0 m/s². However, the measures are not defined and the manufacturer or technical service is not obliged to document the methodology in the test report. This proposal would introduce a table with examples for devices and measures for reference and would require documentation of methodology used.

Proposal to exclude pure electric vehicles, including vehicles with auxiliary electric propulsion, from the scope of the regulation, to include sound-level measurement conditions for powered cycles equipped with compressed air engine and to introduce sound-level limits for powered cycles.

Proposal including indoor testing as an alternative to type approval tests of Annex 3 to Regulation No. 51 including ISO 362-3.