Thanks Flecc, the Dec 15 DfT document specifically says 'to help start up' that is why I am confused.
I know the document you mean, it was Guidance issued in December 2015 and in section 1, subsection 1.2 they state there's an exemption for start up assistance. Unfortunately they've issued several guideline documents and information sheets in the last few months and that is the only one stating this.
I think it's the DfT who are confused, partly because of the complexity of the changes in the law, partly because this isn't an area of the law that concerns them much (last time was 1983!), and partly because there are continuing discussions in the EU about the provisions for throttle controlled vehicles.
It's the actual law that counts and this is the law amending the old 1983 regulations:
The Pedal Cycles (Construction and Use) (Amendment)
Regulations 2015
Made - - - - 3rd March 2015
Laid before Parliament 5th March 2015
Coming into force - - 6th April 2015
It stipulates within that compliance with the EU wide type approval legislation 168/2013 is necessary and that contains the conditions for exemption from motor vehicle law. Here's the relevant paragraph copied and pasted from 168/2013:
(h) pedal cycles with pedal assistance which are equipped with an auxiliary electric motor having a maximum continuous rated power of less than or equal to 250 W, where the output of the motor is cut off when the cyclist stops pedalling and is otherwise progressively reduced and finally cut off before the vehicle speed reaches 25 km/h;
As you can see, that clearly states that power must cut off if the rider stops pedalling. The walk alongside throttle operates without pedalling so isn't legal when riding. What makes that throttle legal are the Pedestrian Controlled Vehicle regulations of 1963 and similar law in Europe, and if someone is riding they are no longer a pedestrian of course.
However, it's a minor point and if you pedal as well when setting off, no-one is going to bother you since that disguises that power is available without pedalling.
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