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jasmin89

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Hi, I've written some stuff together that serves as a basis for discussion (The goal is to discuss some technical details for the new development of an E-bike). Can someone look at this and tell me what I could possibly better formulate?




I would like to discuss the following questions from my engineering perspective:
Do we design an all-wheel drive E-bike? Is regenerative braking possible on an electric bicycle? And what type of braking system should we take?

I would like begin with my first point: In my opinion we should design an all-wheel drive.
The biggest benefit of all-wheel-drive electric bikes isn’t the power. That’s what most people think of when they hear of an AWD electric bike.
Of course, that’s one of the benefits – but I believe that the biggest benefit of all-wheel-drive electric bikes is the stability and comfort. By spreading out the power on both wheels, rides become smoother and riders can feel more control on both of their wheels.
Yes, two motors instead of one can increase the weight of an eBike. However, that’s not a downside. It’s actually an advantage as the added weight on both front and back helps stabilize the eBike more.


I will now come to the second question:
Is regenerative braking possible on an electric bicycle? In my opinion is the answer definitely yes. There are a lot of bikes out there with regenerative braking, but you do need the right components to make it work. It's not possible on every bike. You have to have the right parts. So, first of all, you have to have the right type of motor. The only motor that can really be used for regenerative braking is a direct drive hub motor. So those are the big ones. You can't use these little normal geared motors because there's a clutch in here and they're not directly driven when you're going forward. So you have no resistance.

They're able to regenerate electricity because you're basically driving them forward instead of letting the motor drive you when you coast. Or when you go to break and use regenerative braking, you're actually engaging the motor and that's sending electricity back out the opposite way to charge your battery. For your E-bike we need a gear less direct drive hub motor.

As for the brakes I would suggest to mechanical brakes. Biggest Advantage of mechanical brakes over hydraulic brakes is "price". Cost of an entry level hydraulic brake is at least 2x more expensive than a mechanical disc brake. Also, when assembling bike it needs much more labor work due to complexity of the system. I think another pro for the mechanical brakes is a very easy to adjust. You don't need any kind of special tools. One of the negative side effects that you do need to adjust this every couple of hundred miles as those pads wear down, you're gonna want to tighten that cable up. And that does require adjustment. But again, it's definitely easy to adjust yourself to do yourself sort of thing. You can also service these roadside, which is pretty nice sometimes.
 

Charlie Bernstein

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Hi, I've written some stuff [STRIKE]together[/STRIKE] that serves as a basis for discussion. (The goal is to discuss some technical details for the new development of an E-bike.) Can someone look at this and tell me what I could possibly say better?

I would like to discuss the following questions from my engineering perspective:

Do we design an all-wheel-drive E-bike? Is regenerative braking possible on an electric bicycle? And what type of braking system should we use?

I would like to begin with my first point: in my opinion, we should design an all-wheel drive.

The biggest benefit of all-wheel-drive electric bikes isn’t the power. That’s what most people think of when they hear of an AWD electric bike.

Of course, that’s one of the benefits – but I believe that the biggest benefits of all-wheel-drive electric bikes [strike]is[/strike] are the stability and comfort. By spreading out the power on both wheels, rides become smoother and riders can feel more control [STRIKE]on both[/STRIKE] of their wheels.

Yes, two motors instead of one can increase the weight of an eBike. However, that’s not a downside. It’s actually an advantage, as the added weight on both front and back helps stabilize the eBike more.

I will now come to the second question: Is regenerative braking possible on an electric bicycle? In my opinion, [strike]is[/strike] the answer is definitely yes. There are a lot of bikes out there with regenerative braking, but you do need the right components to make it work. It's not possible on every bike. You have to have the right parts. So, first of all, you have to have the right type of motor. The only motor that can really be used for regenerative braking is a direct-drive hub motor. [STRIKE]So[/STRIKE] Those are the big ones. You can't use those little normal-geared motors because there's a clutch in there and they're not directly driven when you're going forward, so you have no resistance.

Direct-drive hub motors can regenerate electricity because you're basically driving them forward instead of letting the motor drive you when you coast. And when you go to brake with regenerative braking, you're actually engaging the motor, and that's sending electricity back out the opposite way to charge your battery. For your E-bike we need a gearless direct-drive hub motor.

As for the brakes, I would suggest [STRIKE]to[/STRIKE] mechanical brakes. The biggest advantage [STRIKE]of mechanical brakes[/STRIKE] over hydraulic brakes is price. The cost of an entry-level hydraulic brake is at least twice that of a mechanical disc brake. Also, [STRIKE]when[/STRIKE] assembling the bike takes much more labor [STRIKE]work[/STRIKE] due to the complexity of the system. I think another pro for the mechanical brakes is that they're very easy to adjust. You don't need any kind of special tools. One of the negative aspects is that you do need to adjust them every couple of hundred miles. As those pads wear down, you're going to need to tighten that cable up. And that does require adjustment. But again, it's definitely easy to do it yourself. You can also service these roadside, which is pretty nice sometimes.
You have both E-bike and eBike. Use just one.

Online, put spaces between paragraphs. In print, use either spaces or indents to separate them.

You've certainly convinced me!
 
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emsr2d2

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Jasmin89, please don't post yet another "Thank you" post. I have already deleted two. There is never a need to add a new post to a thread to say "Thank you" to anyone. All you need to do is click on the "Thank" button in the bottom left-hand corner of any post you find useful.
 

Tdol

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which is pretty nice sometimes.

This doesn't fit the tone of the article for me.
 

jasmin89

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Can I say this when I agree something:
That’s a good point. I have not yet considered this aspect. For that I agree with you that we should use hydraulic brakes.

Are these sentences okay?:

-For example off road, having some drive available at the front is more useful. In this case, the bike can not pick up the front wheel as the available traction is more limited, the rear wheel would spin up before that.

-I think it is difficult to implement a robot that is changing the battery automatically. A human worker can still do that in a very good way. What I am trying to say is that this step is not easy to make and if complications arise during the change, a worker can still react better to it.
 

Charlie Bernstein

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Can I say this when I agree something:
That’s a good point. I have not yet considered this aspect. For that reason, I agree with you that we should use hydraulic brakes.

You might.

Are these sentences okay?:

-For example off road, having some drive available at the front is more useful. In this case, the bike can not pick up the front wheel as the available traction is more limited, the rear wheel would spin up before that.

That's confusing. I can't picture what you mean.


-I think it is difficult to program a robot to change a battery [STRIKE]automatically[/STRIKE]. A human worker can still do it easily, [STRIKE]What I am trying to say is that this step is not easy to make[/STRIKE] and If complications arise [STRIKE]during the change[/STRIKE], a human can [STRIKE]still[/STRIKE] react better [STRIKE]to it[/STRIKE].
There you are!
 
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