71 test personnel drove along a prescribed test road under the following conditions: when sober with 0.8 promille and 1.3 promille (alcohol contents in the blood) on a bicycle and on a motorcycle. The tests with bicycle indicated at 0.8 promille, compared with the performance when sober, a reduction in performance of 80.6 percent and with 1.3 promille, 81.8%. In the motorcycle tests the performance at 0.8 promille fell by 70 percent compared with the performance when sober. The lower fall in performance compared with the cyclists is based on the fact that with the motorcyclists the performance when sober was already worse. At 1.3 promille there was a reduction in performance of 87 percent. Measured against the performance when sober of the cyclists, the performance of the motorcyclists at 0.8 promille (increased number of errors) was 83.5 percent worse and at 1.3 promille 88.5% worse. Taking these results into account equal legal treatment of cyclists and motorcyclists can hardly be based on similar performance requirements. The courts have however other circumstances to consider, for example the lower danger to other road users due to the low weight and low speed of these vehicles. (TRRL)