The reasons why the Met have taken action against these illegal pedicabs now and a number of times previously over the last few years is twofold:
First, the licenced taxi drivers resent the pedicabs so raise the illegality complaints in the first place.
Second, the law restricts e-trikes to 60 kilos weight, and these pedicabs are far, far in excess of that weight.
That makes the seizure and, if necessary, prosecution very easy. That some are using motors far in excess of what the law permits doesn't need to be pursued, avoiding the complications such a prosecution brings.
Here's what I posted on this subject a short while ago:
On the morning of Thursday the 4th December 2008 the Metropolitan Police conducted an extensive operation specifically to seize a number of illegal EAPCs, arresting the riders. The EAPCs in question were trikes, pedicabs operating in London, falling victim to the 1983 EAPC legislation when their riders fitted e-bike motors to make their life easier. Some of the motors were 250 watts, legal for e-trikes only under our law, but others were illegally higher powered. However, all were illegal under our EAPC law which specifies a maximum e-trike weight of 60 kilos which the pedicabs could not meet. That made the prosecution very easy, no complex legal arguments about motor power needed.
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