e bike from scratch

Electrically assisted bikes, trikes, etc.
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Joined: 8 Jun 2020, 5:35pm

e bike from scratch

Postby 365bpm » 8 Jun 2020, 5:45pm

im new to this forum as ive been interested in an e bike but at the mo all the bike shops are closed :(
after lots of online browsing , I like the idea of a custom bike as opposed to a ready to go off the shelf jobby..
primarily because of the power / speed limiting here.
Does anyone know of a good combo (mens mountain bike style) of bike and ebike kit that could be recommended?
I would purchase a used custom made bike but currently there are not a lot available near me and i wouldnt want it posted.
Id like a lot of wattage (1000 +) and the potential to reach around 35mph (where permitted)
any advice would be much appreciated..
please bear in mond im neby so simple terms please..

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Joined: 16 Nov 2017, 5:40pm
Location: West Sussex

Re: e bike from scratch

Postby hemo » 9 Jun 2020, 10:21am

Ideally for what you want it's called a moped but they need licencing.
Any pushbike or legal ebike will do 35mph down a hill.

No legal kit will do 35mph and the illegal ones that can will cost about £700 - £1000 minimum as the battery you will need will have to be a good one with a whopping capacity and a continuous 40a+ discharge rate.

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Joined: 6 Jun 2018, 10:24am

Re: e bike from scratch

Postby stodd » 9 Jun 2020, 10:51am

I absolutely agree with everything Hemo said there.

Technically what you are suggesting is an s-pedalec (speed pedalec).
For more see https://www.pedelecs.co.uk/forum/forums ... ussion.43/
It is illegal to ride such a bike on the road without license, insurance etc.
It is illegal to ride it off road anywhere with public access (eg bridleway) even with license, insurance, etc.
It can be ridden on private land with landowner's consent away from public access areas.

The technical limit for a legal pedalec is a 250w nominal (continuous) motor and 15.5 mph assisted speed.
Most of these can generate 500w peak or more, many over 700w.
They have much better hill climbing capability than the big 1000w motors,
and don't require such a massive (and expensive) battery.

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Location: Northumberland

Re: e bike from scratch

Postby Oldjohnw » 9 Jun 2020, 4:17pm

No where is 35 mph permitted purely with electric power - more so if a speed limit!

I regularly reach 30+ mph on my e-assist bike. But the motor has long since switched off and I am on my own - with the help of gravity.

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Joined: 8 Jun 2020, 5:35pm

Re: e bike from scratch

Postby 365bpm » 10 Jun 2020, 12:11pm

can people please stick to replying to the questions in threads otherwise topics wander and replies get random and aimless.