Need guidance

Lightweight / Folding / Portable EVs - seats optional
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Joflo   10 µW

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Need guidance

Post by Joflo » Aug 31 2018 11:20pm

Hi,
I stumbled upon y'all's site while looking for a bird type scooter. The fabricator in me searched "modded electric scooter" now I'm here😀😀😀
I have $1800 to spend
1st: I need a scooter immediately for a 16 mile(round trip)daily ride. this scooter I want ready to ride but I also want to modify it in the future.i weigh 210 and want to maintain atleast 20mph (the faster the better) I've looked into these so far
Xiaomi 365

Zoom stryder(with an added battery pack Itll make my trip)

Super cycles 1000(this one seems like the most modifiable)
is the 1500 worth the extra money?

With the left over money what should I get towards the 2nd scooter? I want to build a big scooter like the s1000 that goes at least 45mph but has super acceleration(controlled).
Im going to design the frame (I weld)

I spent a good amount of time reading through the "build your own ev". I would like y'all's expert opinions. I would greatly appreciate any knowledge y'all may have. I'm from Texas BTW

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Chalo   100 GW

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Re: Need guidance

Post by Chalo » Sep 01 2018 12:41am

Man, for that kind of distance, I'd use a bike over a mini scooter every time. What's your rationale? No workable parking? Even a godforsaken folding bike would be more roadworthy.

8 miles each way means a lot of opportunities to stuff that donut wheel in a hole and grate your face on the street.

Keep in mind that the claimed range for these scooters is probably at their most efficient speed (very slow), and they won't go nearly so far at 20mph.
This is to express my gratitude to Justin of Grin Technologies for his extraordinary measures to save this forum for the benefit of all.

Joflo   10 µW

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Re: Need guidance

Post by Joflo » Sep 01 2018 4:16pm

Thanks for the reply. I'm from Austin,tx and were growing really fast and getting really crowded. I've been riding my bike for a year steadily. My daily milage is about 20-25 miles. My problem is that by the time I get to where I'm going I'm all sweaty. Pedaling hard I can maintain 25mph, pedaling moderatly15mph.

After reading your reply I looked into the hub motors for a bicycle.
I have a very lightweight candidate for the frame(only 20lbs). What motor, battery setup, controller would you suggest? I'm looking to just pull the throttle and go, no pedaling. It's a road racing 27.5inch rim. I'd like to spend no more than 1000 for parts on this 50mph rapid acceleration and hopefully 20 mile range per charge
Im working on a design for a big wheel scooter. I really love the riding posture of a scooter.
I'm an entrepreneur so if I can build these in my spare time as a hobby and sell them. That would be pretty cool. Heck Austin's growing so fast I could make a business out of it, there's definitely a market here for it.
Again I appreciate anyone's input

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Chalo   100 GW

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Re: Need guidance

Post by Chalo » Sep 01 2018 8:13pm

50mph and $1000 budget don't really meet at any point. I ran your weight and estimated bike data through the Kreuzotter speed and power calculator. You need about 800W to the ground to sustain 30mph on the flat. 1800W will get you a steady 40mph, and to go 50mph, you need about 3500W-- real mechanical power to the wheel, not electrical energy at some arbitrary RPM. That means to sustain 50mph in neutral conditions, on level ground, you'll need at least 5000 real world electrical watts, and you'll have to do a good job of load and speed matching.

Short version is, you won't get a motor and controller that can take 5000W, Plus a battery that can provide 5000W, for anything close to $1000 total.

If you play your cards right, you can probably get a motor kit and batteries for $1000 that will build into a 35mph bike with enough range to do your round trip. The bike won't be very pleasant at that speed, but it should hold up ok.

For 50mph, the battery alone won't fit in your budget, and the bike won't hold up worth a damn either. None of the motors I know of that can put out 3500W will fit in your road bike frame.

You are on the right track about one thing-- above 35mph cruising speed, you don't need to trouble yourself with pedaling. It costs more in aero drag to pedal at those speeds than your pedaling will contribute to total power. So it might as well be a scooter.

Familiarize yourself with Texas Transportation Code Chapter 551, Subchapter E. That's the part that governs motor-assisted scooters. It's more permissive than what's allowed for an electric bicycle. Know the law and be ready to cite it to a cop.
https://statutes.capitol.texas.gov/docs ... TN.551.htm
This is to express my gratitude to Justin of Grin Technologies for his extraordinary measures to save this forum for the benefit of all.

Joflo   10 µW

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Re: Need guidance

Post by Joflo » Sep 02 2018 5:57pm

Can you point me in the direction of what to buy and where.. I been looking at different sites. I ended up at Luna for the hub motor then looked up reviews about Luna's lack of customer service. Then re-read the bulid your own ev. It states that hub motors aren't as efficient. My question to you is, can I get a steady 25mph with good acceleration out of a hub motor? Where should I buy it? I feel really comfortable buying things on Amazon because I can return it easily if I'm not satisfied but I also don't want to waste my time and labor.

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Chalo   100 GW

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Re: Need guidance

Post by Chalo » Sep 02 2018 6:28pm

Joflo wrote:
Sep 02 2018 5:57pm
My question to you is, can I get a steady 25mph with good acceleration out of a hub motor?
Absolutely yes. Which hub motor is best for that job depends greatly on what wheel diameter you use. So, what wheel diameter are you going to use?

Steady 25mph is a totally different ballpark than 45-50mph. Electric propulsion is not like gas motors. Reasonable cruise speed is likely to be 90% of maximum speed. Regular e-bike stuff is usually usable for 25mph. To go 50mph, you're in the market for special ingredients.
Where should I buy it? I feel really comfortable buying things on Amazon because I can return it easily if I'm not satisfied but I also don't want to waste my time and labor.
Luna has been fine to me, and I appreciate that they are in the same country as me. EM3EV (cellman) is a native English speaker in China who goes the extra mile to provide top quality goods and solid customer support. Grin Tech is unsurpassed for quality, service, and expertise. They're in Canada, so that slows things down a bit, and the prices are First World (but worth it if you can afford them).

Your problem to solve is mostly not about the motor, but the battery. Reckon you'll need 600W at the wheel to cruise at 25mph on flat pavement. Reckon further that you can realize 70% efficiency from battery to wheel. So you need about 850W electric power to roll at 25mph. That's about 18 amps at 48V. Double that so you can climb and accelerate affirmatively. Thus you are looking for a system that can transmit 35ish amps at 48V. If the motor and wheel give you a no-load speed of about 35mph, then cruising at 25mph in varying conditions should be realistic.

So, you're looking for a motor that won't overheat at 35A, that spins at a surface speed of 35mph at 48V when the wheel is held up off the ground. That narrows the choices down somewhat. But it's still highly dependent on wheel diameter.
This is to express my gratitude to Justin of Grin Technologies for his extraordinary measures to save this forum for the benefit of all.

Joflo   10 µW

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Re: Need guidance

Post by Joflo » Sep 02 2018 7:21pm

I have several bikes from the one I'm looking to build firs would most likely be the 20inch

Joflo   10 µW

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Joined: Aug 31 2018 9:57pm

Re: Need guidance

Post by Joflo » Sep 02 2018 7:41pm

https://www.hyperpowersports.com/produc ... s-red.html
Do you think this would fit my immediate need? I've read some reviews and it seems like the only problems are the connections, I can solder those together when I get it to avoid that problem

Joflo   10 µW

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Joined: Aug 31 2018 9:57pm

Re: Need guidance

Post by Joflo » Sep 02 2018 7:43pm


e-beach   100 MW

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Re: Need guidance

Post by e-beach » Sep 02 2018 8:21pm

Like Chalo has stated. 48v and 15ah to 20ah battery with a 30 to 40 amp controller. If you aren't going to pedal, a 48v direct drive (also called a DD hub motor) for your rear would suite your needs. If your controller can take the extra voltage, you could always over volt the motor by 12v to 24v. Just don't over heat the motor and fry it. Remember, you are on a bicycle frame not a scooter or motorcycle frame. You are adding weight and inertia so every part of the bike takes a pounding.

If you are into pedaling sometimes, then a geared hub motor that will freewheel while not in use. Depending on how you abuse your motor, sometimes the internal gears go bad. You might even consider a mid drive motor.

Make sure your torque arm is well installed so the motor doesn't crack out of the dropouts.

I have had good success with my yescomusa.com kit. https://www.yescomusa.com/products/brus ... -motor-kit

Others have as well like Wesnewell viewtopic.php?f=3&t=66302

I always advocate putting your batteries in the triangle of the bike for best weight distribution.

:D
.
Favorite Quote: "This is L.A., sugar. There is no 'over the top." --- Chris Erskine

Current build: Liahona w/ cheap front suspension and suspension seat post. Yescomusa 36v 800w generic front hub motor. 15ah Headway triangle mounted pack. Tronsung 30 amp,

Previous Build:1992 Trek Antelope 800 - Bone Crusher (no suspension) - Yescomusa 800 watt 36 volt front wheel kit. Don't do it! Get suspension!!!

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