Looking for people that own E-bikes

[eCue]

IMO the e components matter more then the bike platform ,shop smart as price paid is not always relative to its performance. I have noticed $2000 ebikes have about $400 or $500 of e-parts including batteries on them the rest is glitter.

 

[John and Cecil]

Ok you got my interest in building an E-Bike.

I have looked at a few videos and the big issue I see is the battery size and cost. I see the cheapest method is to daisy 4 12 volt batteries together. But that adds 30 lbs to the bike.

What are your suggestions for the lightest inexpensive battery?

I would like to start out with an Basic Amazon Kit and a basic bike and go from their.

Thanks for any input

It depends on the range you are looking for and the motor that you will be using. We are currently using a 56v 2ah ego power tool battery for power. I bought it on ebay when they had a coupon and it came out to $42 and it was new still in the packaging along with a used charger. This battery is only good for 4 to 5 miles though.

I cannot help you with hub motors/kits, I ride a lot of steep hills and a mid drive motor is pretty much a necessity (or possibly a quality heavy duty, and probably not legal, hub motor). A mid drive motor (it replaces the crank and chainring rather than the wheel) allows you to use your bike's gearing with the motor so you can shift into low gear to climb hills and then shift into higher gears on the flats for top speed. I am in the process of changing my gearing though, my drivetrain at the moment will allow 10mph at 90rpm in 1st gear and 30mph in 8th gear but we are having difficulties climbing hills greater than about 8-10% grade without pedaling (rider weight + dog passenger = 215lbs). I have mid-fat tires too and the only time we get near 30mph is when we are going down hill. With a wider ratio rear cassette (11-32 will eventually be swapped with 11-40) and smaller front chainring (42t will eventually be 34t) our new 1st gear will be 6.5mph @90rpm and 8th will be about 23mph. This should allow us to climb perhaps 12-15% grades at 5mph without pedaling.

You cannot swap hub motor gearing so you need to design your bike for the environment in which you plan to ride first. A lot of people have hub motors and they like them, and they can also be a cheap build too. But I would not want one if I were riding in say San Francisco, at least not a cheap one that will burn up on all the steep hills. I suggest before you buy a kit determine hills, range desired, weight, speed desired, etc very carefully and then you can choose the setup that best suits your needs.

 

[Alan B]

Ego has 7.5 amp hour packs for additional range. Some vendors have reduced pricing on these packs. A pair of these in parallel at 15 amp hours is a fairly long range setup.

For the same power the mid drive may have the best hill climbing, the geared hubmotor second best and the direct drive the least.

However the direct drive will generally handle more power and with more power it may exceed the performance of the other two.

 

[rumme]

Ego has 7.5 amp hour packs for additional range. Some vendors have reduced pricing on these packs. A pair of these in parallel at 15 amp hours is a fairly long range setup.

For the same power the mid drive may have the best hill climbing, the geared hubmotor second best and the direct drive the least.

However the direct drive will generally handle more power and with more power it may exceed the performance of the other two.

The direct drive hub motor, if properly set up { laced to small rim, phase amps set properly, ferro fluid , hubsink heat fins, proper tires, properly matched to controller/battery upgraded phase wires, etc} can generally handle most hills/ torque that the majority of ebikers will ever be subjected to. The problem with direct drive hub motors is most people expect to much out of them, when they are improperly setup/matched for their desires....for example, buying a sondors ebike and thinking it is setup to be a torque monster and propel a 200 lb rider up a road that has a 7-10% incline for 1/4 mile. Generally speaking, anyone that is using a direct drive hub motor in a 26" wheel, and is wanting high torque, is doing things wrong.

I really like the setting on my ebike. 3kw-5kw direct drive hub motor, with the controller set so it can achieve 45mph top speed on flat roads with it programmed at 80amps max output and 120 amps phase , which gives me good torque to go up hilly roads, but not so much torque that it overheats the components. I weigh 210 lbs and my setup is damn near perfect. If I hammer the throttle, I can feel it has good torque, but not to the point of it wanting to pull wheelies, because I have no need for that much torque nor would I want to stress the compnents by doing wheelies.

I guess if a person wants a wheelie machine ebike, or needs to constantly be adjusting their ebikes torque/top speed ratios for many different terrains, then mid drives are the best way to go. So in that respect, the hub drive may not keep up. I personally dont like having to switch gears or the stress on the components that a mid drive offers. Simplicity often means less worries and less breakdowns. Direct drive hub motors are the king in those area.

 

[LockH]

Ok you got my interest in building an E-Bike.

I have looked at a few videos and the big issue I see is the battery size and cost. I see the cheapest method is to daisy 4 12 volt batteries together. But that adds 30 lbs to the bike.

What are your suggestions for the lightest inexpensive battery?

Might suggest you look at overall cost (re the battery) PER MILE/kilometer before eventual recycling and replacement? Like, I used to "burn up" lead-acid batts in less than one summer... within a few hundred cycles... Whereas lithium-flavoured chemistries are more expensive to purchase but can last a thousand and more discharge/recharge cycles... and require less energy to accelerate from stops and go "hill climbing", etc. due to being less weight than SLAs.

:wink:

 

[John and Cecil]

Yeah I would avoid the lead acid battery route. Actually the cheapest battery out ther might be the lowes 24v max 1.5ah lithium battery packs which cost $8 each after 20% off coupon. 2 of them connected in a series creates a 12s1p configuration which I guess is about a 44v battery. If you have a motor that can run on a 12s configurations and can come up with a way to safely join a bunch of them together it could be a very inexpensive lithium battery solution.

 

[Alan B]

The cheapest lithium battery may have a short life, and may not be the cheapest per mile. Ebikes draw more power than the usual power tool. You want something that is cheap per mile, not necessarily the same as the cheapest in up front procurement cost.

Gradients are a very important thing to consider. Also rider plus bike (system) weight.

If you are riding in a flat area, the answer is different than if you are riding in something hilly like San Francisco.

For me 15% gradients are fairly common. A low power DD hub may stall on this gradient (and overheat), whereas many geared hubmotors or any mid drive will climb it readily. A DD hubmotor with 4-5kW will climb 15% and maintain 20 mph while doing so.

 

[John in CR]

You won't get it until you build your own, but the satisfaction of building your own primary transportation with absolute reliability is hard to beat. No ready built ebike can offer that. Plus their performance in a word "sucks". Add in that's it's relatively simple to built for performance levels that laugh at motorcycles and cars that's like the best amusement park rides, but no lines and pennies a ride, and you're able to plant a permanent smile on your face with a hobby that quickly pays for itself.

 

[rumme]

For me 15% gradients are fairly common. A low power DD hub may stall on this gradient (and overheat), whereas many geared hubmotors or any mid drive will climb it readily. A DD hubmotor with 4-5kW will climb 15% and maintain 20 mph while doing so.

Yes. My direct drive hub motor is rated at 3kw....but I mounted it in a 19" rim and its treated with ferro fluid, so I can run 5kw bursts thru it and it does not overheat and handles the hilly roads in my area with my 210 lb bodyweight. I like this setup more then a geared hub motor or mid drive system, because a geared hub motor usually limits your top speed and mid drives involve to much wear and tear on components and involve much more gear changing. I like the simplicity of just turning the throttle and getting the performance you need. A typical generic 750-1000 watt direct drive hub motor / controller system, cant offer that, especially if the rider weighs more then 160 lbs and wants high top speed and good torque. I do think that for most scenarios , a 48 volt or higher , direct drive hub motor that can handle 1500k nominal and 2500k bursts is enough to satisfy most riders / situations .

 

[Streamingpete]

Thanks for the info on motor size. I am 210 lbs and want the correct motor.

 

[Alan B]

Choosing a 3kW DD hubmotor vs a 750W mid drive or geared hubmotor changes things in a fundamental way. This approach leads to a larger battery pack with higher current and amp hour capacity, heavier motor, and a need for tougher rims and tires. The result is a much heavier machine. While a mid drive or geared hubmotor bike with front suspension and bicycle tires can be around 60 pounds, a 3-5kW capable hubmotor bike with full suspension, moped rims and tires will be well over 100 pounds.

 

[John and Cecil]

Thanks for the info on motor size. I am 210 lbs and want the correct motor.

A mid drive like the bafang bbs02 or the tsdz2 750w might be a good starting point. They are fairly easy to install (a couple of hours maybe) and they use the bikes existing gearing so they will be able to tackle hills or go faster on flat areas. The tsdz2 has less power than the bafang but it has a better torque sensor and adjusts it's power assist according to how hard you pedal. The bafang bbs02 is more powerful (programmable up to 1300w) but it does not have a torque sensor and it assists by merely moving the pedals. Both units can have throttles and the tsdz2 costs about $375 and the BBS02 about $500, and each will fit most bikes with a 68 or 73mm bottom bracket width. Bafang also makes an even more powerful heavy duty mid drive BBSHD motor but it is more expensive ($750) and that motor can also fit on the larger fat bike bottom brackets.

I am sure some other people can recommend some powerful but inexpensive hub motors for you too. We are pushing the same weight as you, I think the terrain and hills where you ride is going to be a very important factor for making a decision, especially when you will be pushing close to 270lbs rider, bike, and gear. I think the mid drive might be better for a first build if you are going to be taking on hills and you want a legal motor.

 

[John and Cecil]

Yes. My direct drive hub motor is rated at 3kw....but I mounted it in a 19" rim and its treated with ferro fluid, so I can run 5kw bursts thru it and it does not overheat and handles the hilly roads in my area with my 210 lb bodyweight. I like this setup more then a geared hub motor or mid drive system, because a geared hub motor usually limits your top speed and mid drives involve to much wear and tear on components and involve much more gear changing. I like the simplicity of just turning the throttle and getting the performance you need. A typical generic 750-1000 watt direct drive hub motor / controller system, cant offer that, especially if the rider weighs more then 160 lbs and wants high top speed and good torque. I do think that for most scenarios , a 48 volt or higher , direct drive hub motor that can handle 1500k nominal and 2500k bursts is enough to satisfy most riders / situations .

I wonder how difficult it would be to get something like this street legal in Europe. I don't think anyone is going to be fooled into thinking it is a 350w bicycle I would love to build something like this that could be ridden at highway speeds there I have been looking at electric motorcycles but they are pricey and the range is not great and they are heavy too - 300 - 400lbs. I would like an alternative to a gas powered motorcycle. I was looking at the KLX 250, supposedly it gets close to 80mpg.

 

[rumme]

Choosing a 3kW DD hubmotor vs a 750W mid drive or geared hubmotor changes things in a fundamental way. This approach leads to a larger battery pack with higher current and amp hour capacity, heavier motor, and a need for tougher rims and tires. The result is a much heavier machine. While a mid drive or geared hubmotor bike with front suspension and bicycle tires can be around 60 pounds, a 3-5kW capable hubmotor bike with full suspension, moped rims and tires will be well over 100 pounds.

3kw of power certainly requires a more beefy frame, spokes, when compared to 750 watt hub motors . Yes, the ebike will weigh more, but the performance is much better . I personally would not feel very safe with a 3kw-5kw hub motor mounted on a typical bicycle frame , but do understand that a normal bicycle frame can handle 1kw or less motors quite well if setup properly.

Ive had a rear hub motor on 48 volt battery doing 1500 watts on a Gravity fat bike which is a lightweight aluminum frame. It was alot lighter then my current ebike which is 3kw-5kw on 72 volts setup on a all steel stealth bomber type frame, motorcycle tires, heavy gauge spokes, etc. It probably weighs 2x as much , but it performs so much better as far as top speed, torque, suspension , etc. Sometimes the extra weight isn't a bad thing if the ebike is properly made with components that achieve the riders needs without over stressing the battery/motor/ controller/phase wires, etc.

a standard ebike compared to a stealth bomber styled ebike are truly like comparing apples and oranges. One is more of a lightweight bicycle setup with a motor, that can still be comfortably ridden using only the pedals, and the other is more of a moped/ motorcycle setup with a motor where the rider probably wont be using only pedal power, to often.

 

[Alan B]

3-5 kW is not really adequate for safe operation at highway speeds, nor is a moped weight machine. That's motorcycle range, and they are up to 30 or even 60kW and 300-400 pounds for many reasons.

Depending on where in the world you are, the rules for ebikes can be very different, and the level of enforcement as well. This must be taken into account in the build planning.

 

[rumme]

3-5 kW is not really adequate for safe operation at highway speeds, nor is a moped weight machine. That's motorcycle range, and they are up to 30 or even 60kW and 300-400 pounds for many reasons.

Depending on where in the world you are, the rules for ebikes can be very different, and the level of enforcement as well. This must be taken into account in the build planning.

Luckily I do not use my ebike on the roadways at highway speeds. I only drive on the sides of roads, backroads and usually stay at 25 mph or less. ..which is about 1/2 throttle. The main times I use 3/4- full throttle is to ascend the several steep hilly paths in my area, which allows me to stay at 25 mph going uphill around full throttle. If I did full throttle on flat areas...it would do about 45 mph , but I dont use the power that way.

Im not a ebike speed demon , I just learned that a typical 1000 watt hubmotor ebike, is lethargic on the local steep roads , even at full throttle it bogs down. The 3kw- 5kw power on my current ebike, is most often accessed for those steep inclines to keep the ebike moving at 20-25 mph without overheating the motor itself or pushing the motor well beyond its limits. Much of this is how a person uses the extra power/ speed. Whenever I see a cop , I always start the motion of pedaling to make it known that this isn't just a powered moped/motorcycle.

 

[John and Cecil]

I have ridden 200lb motorcycles on the freeway at 80mph. You just have to know what you are doing (how to shift your weight, etc). We used to ride modified 50cc mopeds at 50+ mph when I was a kid on major roads without issue and they only weighed 100lbs. With wider tires, strong suspension, a lower center of gravity, triple tree heavy duty fork, etc a heavy duty ebike should be more than capable of highway use. Perhaps a large electric mid drive motor pushing 10-15kw with a 2 or 3 speed transmission or a heavy duty hub for gear changes. Maybe the best option is to buy an older e-motorcycle without batteries and then build your own lighter battery.

 

[Alan B]

It is really nice to have a power surplus. More than nice, it is a safety feature. Power limitations on ebikes don't generally provide any margin, and the manufacturers of commercial products usually abide by those rules. So the first time you hit a big hill the bike cannot maintain even 20 mph. Then it becomes less safe as more traffic passes than would happen if the ebike could maintain speed on the grade. Many more chances to meet that texting driver.

Sure, people drive on the freeway with light motorcycles, but it is not considered terribly safe by motorcycling experts. Similar to driving the family minivan at 100 mph. It is just beyond the usual safety envelope.

Anyway, highway speeds are getting away from from this thread's purpose.