Lack of proper labelling, virtually no pedelecs are correctly marked in every respect. Here's what the law says, the first way is for current machines built to EU standards, the second for 2015 and before machines. (Forget about kit builds, a police officer isn't qualified to determine if an e-bike is kit built or just a non standard manufactured one.):
"Must be fitted with a plate securely fixed in a conspicuous and readily accessible position showing— (a) the name of the manufacturer of the vehicle, (b) the nominal voltage of the battery (as defined in the 1971 British Standard) of the vehicle, and (c) the continuous rated output (as defined in the 1971 British Standard) of the motor of the vehicle;
or (ii) visibly and durably marked with— (a) the name of the manufacturer of the vehicle, (b) the maximum speed at which the motor can propel the vehicle specified in miles per hour or kilometres per hour, and (c) the maximum continuous rated power (as defined in the Electrically Assisted Pedal Cycles Regulations 1983)(d) of the motor of the vehicle specified in watts or kilowatts;”
If not plated in one of the above ways, suspicion exists that it may well be illegal since it's well known that there are numerous illegal e-bikes and other two wheelers on the roads.
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