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Discussion Starter #1
As some of you may already know. I am from the R/C insdustry and I know a lot on those. I am french and my english writting is suceptible of having many flaws.

Before building an EV I decided to build an E-bike first

The pedal bike will be a street pedal bike (no suspentions and very slim tires)

This is my intentions;

1- To keep the pedal bike fonction
2- To be able to use the electric function when ever I want

Im aiming for a Carbon fiber street pedal bike within 10LBS in weight. Im thinking of getting a used Specialised for 500$ or a used trek for 500$



I would like to travel long distances (for pedal bike) 20-50km (no hill climbing)

and I would like speeds from 40-60km/h I might be impossible but I'd like to build this project with my DiY buddies and advices

Let's discuss

1. Which bike would be the best bang for the $
2. Should I use my Hobby componments BLDC (from 1400kv to 2650kv) Controller rated at 22.2volts 210amps. controler with built in software to adjust current limiter, cutoff (lipo), timming, boost, drag, brakes and can be run sensored or dual mode. Downside is that I am limited to 22.2v @ 210amps (best RC ESC) for only 329.99$




If you have better electronics please let me know but please NO BRUSHES
 

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Is that 210 A peak or continuous? That's 4.6kw, which should be plenty. If it's peak you could only do that for a few minutes at most, and the continuous rating would determine if that would work well.

After seeing your RC video I'm tempted to start another project. :D
 

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Discussion Starter #3
Is that 210 A peak or continuous? That's 4.6kw, which should be plenty. If it's peak you could only do that for a few minutes at most, and the continuous rating would determine if that would work well.

After seeing your RC video I'm tempted to start another project. :D
It's continuous! Wait before that I am making a video just for you guys here!
I will talk a little showing you the setup for the RC and the software then I will take it for some speed runs

what is this new project your talking about?
 

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It's continuous! Wait before that I am making a video just for you guys here!
I will talk a little showing you the setup for the RC and the software then I will take it for some speed runs

what is this new project your talking about?
Probably just fooling around with a real basic, entry level RC kit. I've never really fooled with them before but that was awesome. :D
 

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Do you have any regulation over the power and function that you are allowed to have on a road legal bike where you are?

My understanding here is that we have quite stringent regulation over the maximum continuous power (250W I think it is) for a bike and it is not allowed to be able to power the bike over 15mph. In, I think, addition the UK laws still allow the motor to be independently controlled by a hand throttle but EU regulation says that it must only offer assistance during pedaling and must reduce assistance as the speed approaches 15mph.

Sadly the EU regulation seems to be one enforced even though the UK law should over ride it resulting in not being able to easily buy Ebikes that are throttle controlled.
 

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Discussion Starter #7
Where do I see all these laws? Even if it is not legal I can always hide de battery pack and motor under something like this

 

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Where do I see all these laws? Even if it is not legal I can always hide de battery pack and motor under something like this
I don't know, maybe a local cycling club or forum would know one way or the other on electric bikes.

I know that some UK people who motorise their bike will say that the only thing a police officer can go by is the continuous rating sticker on the motor.
If it says 250W continuous then it is fine even is it is 4kW peak for getting up hills.:D
It is unlikely the officer will check the spec of the controller if it isn't easily visible so you could have a grip throttle that allows 250W and a boost button that allows everything else.;)

The main thing that would give it away would be a bike doing 40mph with no 'frantic pedaling'.:D
 

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Discussion Starter #9
I started to make plans for the bike and I was wondering how to mount the motor and how to attach it to the drive system without removing the pedals

I thought of a front wheel drive system this way I could assist the motor while hill climbing or simply to save the batteries

What you guys think?
 

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Discussion Starter #11
Wow nice but is 48 volts enough? I mean I really want to build something fast that will be able to travel long distance

Thank you for showing me I think I will go with the 3rd link but still unsure
 

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Discussion Starter #12
thanks for showing me

Should go for the kit (external motor) or the wheel motor?

AWD Bicycle is very very tempting lol
 

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Discussion Starter #13 (Edited)
I will use Dual 48v 1000W Wheel motor with a switch to disable Rear or Front motor for power saving

They say it's rated at 50-60km/h or 30-36 MPH

how many AH should I use? for 40Miles trips?

Come on guys give me some thoughts!!!!!!!!
 

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Wow nice but is 48 volts enough? I mean I really want to build something fast that will be able to travel long distance

Thank you for showing me I think I will go with the 3rd link but still unsure
A lower voltage won't require you to go a shorter distance. It will depend on the type of battery you're looking at. Keep in mind most golf cars are 48v. You won't be going as fast as a golf cart can, most likely, and they can go a pretty fair distance holding four people and their clubs. I'm pretty sure you won't have a problem with a 48v bike.

I don't really know how to estimate the Ah drawn on a bike, or counteract how much energy you'll put into it pedaling, if any. But some of the light cars are getting low 200s, so with just a number to kick around like 50 wh/mi, at 40 miles that's 2000 wh. That's 41 ah. And I suspect that that number is still very high. You might want to scope out what the smallest deep cycle batteries would be available to you and see how it does.
 

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Discussion Starter #15 (Edited)
A lower voltage won't require you to go a shorter distance. It will depend on the type of battery you're looking at. Keep in mind most golf cars are 48v. You won't be going as fast as a golf cart can, most likely, and they can go a pretty fair distance holding four people and their clubs. I'm pretty sure you won't have a problem with a 48v bike.

I don't really know how to estimate the Ah drawn on a bike, or counteract how much energy you'll put into it pedaling, if any. But some of the light cars are getting low 200s, so with just a number to kick around like 50 wh/mi, at 40 miles that's 2000 wh. That's 41 ah. And I suspect that that number is still very high. You might want to scope out what the smallest deep cycle batteries would be available to you and see how it does.
Can I plug 2 motors on a single controller? Is that bad for the controller?

48v 1000w per motor. Controller is listed as 48v and 1000w
I am guessing it will be 1000w too weak.
for twin motor I would have to use the 48v 1000w controler with the 48v 500w wheel motor?

If I install 2 motors front and rear and while cruising I decide that I can turn off the front motor (to save power) will it create a rolling resistance even if the motor is brushless?
 
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