A Couple Newbie Questions About Building An E-Scooter

[Electric Earth]

I'm looking to build a small E-vehicle to get around town mostly on bike paths and side streets and have been thinking about doing a scooter rather than a bike this time. I like the idea of the smaller size and weight. I was thinking of using a 20" wheel platform. I know I at least want a disk brake in the front.

So far the cheapest usable looking scooter I've found is the Toucan 20" for ~$250. Any ideas on other/better options? I don't think I need suspension since I won't be doing any off-road, but maybe I'm wrong and suspension fork would be best?
https://www.bikehighway.com/catalog/product/view/_ignore_category/1/id/756/s/toucan-20-suspension-kick-bike-scooter/

For a motor I want to go with a small geared hub motor. Do these scooters usually have 100mm hub spacing, so a bicycle front hub motor is the way to go? So far I'm thinking of the Bafang G311. I would probably run a regular 36/48v "shark" battery pack.
https://www.ebikes.ca/product-info/geared.html

The only electric scooter I've ever ridden has been one of the Lime rented types. I found them to be sketchy, to the point of basically dangerous at higher speeds. Am I correct in assuming a scooter with 20" wheels and disk brakes will be suitable and stable for going ~20mph?

 

[amberwolf]

I'm looking to build a small E-vehicle to get around town mostly on bike paths and side streets and have been thinking about doing a scooter rather than a bike this time. I like the idea of the smaller size and weight. I was thinking of using a 20" wheel platform.

Realistically, a 20" push scooter isn't likely to be much, if any, lighter than a 20" bicycle. May even be heavier if it's a cheap scooter frame using thickwall mild steel tubing.

By the time you stick motor/batteries/etc on there, the difference will probably be irrelevant.

For a motor I want to go with a small geared hub motor. Do these scooters usually have 100mm hub spacing, so a bicycle front hub motor is the way to go?

Probably, but you'd have to check the specific scooter yo'ure after. There is *some* informaiton in some of the existing threads about converting push scooters; sorry I don't have any links.

The only electric scooter I've ever ridden has been one of the Lime rented types. I found them to be sketchy, to the point of basically dangerous at higher speeds. Am I correct in assuming a scooter with 20" wheels and disk brakes will be suitable and stable for going ~20mph?

Just like anything else, that depends on it's geometry, steering, brakes, tires, etc etc---but remember that these things were generally desigend to be kicked along at human speeds, maybe a fast jog at best, so unlike bicycles in general, not intended for those speeds. So they may have twitchy steerng or other undesirable issues at higher speeds than they were setup for, that might require frame modifications (steering angle, etc) to fix.

 

[macribs]

If this was my project I would look for used bargain stand up scooters. Or even go balls deep and make it yourself for true lightweight stand up scooter. Imagine you lugging that thing up and down the stairs in your building, several times a day maybe. As fun as those are to ride for 5 minutes I am not certain I would sink money into one, or even build one. Everything e-bike ends up costing way more then budget

If you are thinking in terms of ease of use, portability etc why not go electric skateboard, long board or all-terrain-board? Sure they can be heavy as well, especially those all-terrain 4wd boards, with suspension and those are sort of a bitch to lug around, but you can easily take it with you on the tube, buses, trains etc. Keep it beside your desk at work, charge it there if need be and don't have to worry about people stealing your shit. A simple electric skateboard is easy in all senses, light weight, small footprint, low cost (can be - or not!).

 

[Electric Earth]

Realistically, a 20" push scooter isn't likely to be much, if any, lighter than a 20" bicycle. May even be heavier if it's a cheap scooter frame using thickwall mild steel tubing.

By the time you stick motor/batteries/etc on there, the difference will probably be irrelevant.


Just like anything else, that depends on it's geometry, steering, brakes, tires, etc etc---but remember that these things were generally desigend to be kicked along at human speeds, maybe a fast jog at best, so unlike bicycles in general, not intended for those speeds. So they may have twitchy steerng or other undesirable issues at higher speeds than they were setup for, that might require frame modifications (steering angle, etc) to fix.

Just based on a couple websites, they say the scooter is 23lbs or 25lbs depending on which site you want to go on. That's lighter than converting a full suspension MTB, which would be the option if converting a bike. Then you're talking 30lbs or more. The scooter can also get away with a smaller, lighter motor. I'm not going to be happy putting along at 15-20mph on a bicycle, and I know from experience I don't enjoy sitting there like a pud just using the throttle. I actually found with my last build that I'm just not even comfortable sitting there doing nothing on the bike using the throttle. My neck gets stiff and my shoulders tense. I'm going to want to pedal and I'll be a sweaty mess by the time I get to work when it's 80-95 degrees out. If I build a bike, it's going to be a big, heavy, 35mph full suspension bike that's going to end up costing $500+ more, weigh more, and take up more room. I was thinking of building a fast-ish, long distance ebike for basically all of my travel, but I think I've traded that idea in for just using my truck for longer trips and building a small electric for around town use when I don't want to use my regular bicycle.

For twitchy geometry, would that be something as simple as adding a longer fork to slacken the steering angle, or would it likely take more than that to stabilize it?

 

[Electric Earth]

If this was my project I would look for used bargain stand up scooters. Or even go balls deep and make it yourself for true lightweight stand up scooter. Imagine you lugging that thing up and down the stairs in your building, several times a day maybe. As fun as those are to ride for 5 minutes I am not certain I would sink money into one, or even build one. Everything e-bike ends up costing way more then budget

If you are thinking in terms of ease of use, portability etc why not go electric skateboard, long board or all-terrain-board?

I live in a house these days, so no need to worry about lugging up and down stairs. I would actually just park it in the garage and take the battery inside to charge. This would primarily just be for commuting to work, so just once per day dealing with charging too. I was thinking about just converting a cheapo 12" wheeled scooter from craigslist. I suppose I could always do that first and see if I like it. I could just use whatever is the cheapest 12" motor/wheel I can find. Then if I decide I do like it and want to have a nicer one, I'm only out the cost of a cheap rear wheel/motor. Everything else would swap over to the nicer one. If I decided I didn't like the scooter, I would have saved myself the money buying a nicer scooter.

As for the powered skateboard, well, I don't want to kill myself. :lol: Those things just seem dangerous to me, and I've seen too many videos of people crashing with them. You're just standing atop a flat board with small wheels zipping along at 20mph. That sounds like a fun recreational activity on appropriate terrain, but not ideal for commuting on a mix of bike paths and crappy roads every day.

Out of curiosity, what is the build cost on one of those? Having built a couple ebikes now and general research on this forum a lot, I know I can spend $500 and have a totally functional, reliable, simple ebike. Those skateboard builds are a mystery to me.

 

[amberwolf]

Just based on a couple websites, they say the scooter is 23lbs or 25lbs depending on which site you want to go on. That's lighter than converting a full suspension MTB, which would be the option if converting a bike. Then you're talking 30lbs or more.

What do you weigh? Plus the electrics? 5 to 10lbs of bike won't make any significant difference to the final in-use weight, or the power needed to move it. Let's guess the electrics and anything else you add is 25lbs. Let's guess your weight is 150lbs. So there's 180lbs, plus say 25lbs of scooter, for a total of 200lbs. The bike would, if 10lbs more, would be 210lbs with the same stuff on it.


Something else you might think about is that the aerodynamics of you standing upright on the scooter will take more power to overcome, vs common positions on a bicycle, all else the same, for the same speeds. So the electric system would have to be the same for each one, for the same results. (doesn't apply to 35mph bike, just same-capability systems).


Not that it matters if the reason you want to use the scooter is not solely or primarily the weight...but if weight is a main factor, you might reconsider your reasons.


Regarding wheel size...the smaller the wheel, the worse the ride on non-smooth roads. The worse the road conditions, the larger diameter wheels you will need (regardless of suspension) to help negate them.


Suspension...until you get into some of the >$100+ (per wheel) stuff, and even many of the cheaper ones of those, you don't get much (if any) help with anything more than small road imperfections, and cheap forks tend to be flexy and often dont' respond very well simply because of that (they may even tend to bind and not operate with hubmotors in them, due to either torque action or due to wider-than-usual axle shoulders forcing the fork tubes against the stanchions enough to cause enough friction to stop normal movement).

I've only ever had one of the more expensive suspension options (an old Manitou Skareb) but it was the only one that really did much; the next best was a Suntour XCV (I think) but it wasn't very good, and everything else was either nearly or completely useless, including everything that actually came on any of the bikes I had. Sometimes it seemed at the time that it helped, but I usually found after a while that the help was so minimal I was better off with a rigid fork (gave me better control without the flexiness of the cheap suspension).



Everything is a compromise, so you just have to decide what specific things are most important to your goals, and make sure those things are covered well, and then sometimes give in on lower priority things to ensure you can cover the most important stuff.


Regarding the steering/etc at higher speeds, what exactly you would need to do to fix it depends on the existing geometry of what you start with, and how it behaves. Sometimes it's just a trail/caster thing, and sometimes it's a rider-position thing, etc. If you have ridden something that handles the way you want the new one to, under the same conditions the new one will be used, then you can try to make sure the new one has similar geometry/trail/weight distribution/etc., and it should then handle similarly.