Need Help Choosing Components for First E-Bike Kit

[Dan K]

Hi,

New to the forum and thinking about building my first electric bike. This post is going to be somewhat lengthy, as I figure it’s best to get all the info out there so people know what I’m trying to get at and what my requirements are.

First, my skills. I’m an avid cyclist, pretty good mechanic (cars, trucks, dirt bikes, pedal bikes, you name it) and competent with electrical stuff, but by no means an electrician. Most of my electrical experience comes with RC planes. Because of the RC plane history I am heavily biased toward A123, aka LiFePO4 batteries.

My goals:

• 
  20+MPH cruise, unassisted, for 40 miles.
  Ability to climb hills at a decent rate of speed (not riding up the white mountains, but I’ll still have some noteworthy hills to contend with. Stuff that slows me to 8MPH or so on a pedal bike, I don’t know the grade.
  The ability to pedal unassisted (I assume this requires a freewheeling model)
  Stealth, to avoid police issues if pedaling downhill above 20MPH (I’ll hold @ 20 on the flats, that is not an issue)

Other considerations:

• I would not mind a 30 mile range with the ability to swap batteries, if carrying and buying 2 batteries was not too big a deal
  I would really like something that can handle getting wet and dirty, if possible

I was initially inspired to use RC gear, since the motors can be so efficient and I am familiar with the gear. Unfortunately, I think the fabrication required to get a RC setup to work on a bike would involve too much machining, something I cannot do. It would also kill my stealth idea. This brings me back to hub motors. A rear hub motors also allows me to hide most of the electric parts under panniers, while storing batteries, controllers and chargers in the panniers.

I’m leaning toward a “29er” (700C) single speed steel MTB that I already own as a donor. I’m not married to that, and may buy a 26” wheeled bike to use if that makes more sense.

I have been leaning toward a Golden setup.
Option 1:
36V 500W with 16AH Lithium Battery
$788
Option 2:
36V 750W with 16AH Lithim Battery
$820.
Option 3:
48V 1000W with 20AH LiFePO4 Battery
$1,041.

The disadvantages of option #3 are the battery does not come in a nice metal case, the charging system is more cumbersome and a second battery is far more costly. If I needed the 48V 1000W 20AH to meet my requirements I would live with these difficulties.l

Then I came here. Golden products do not seem to be well spoken of. Used, prepackaged, issue-prone products. Not good.

I’ve also read of geared motors. Do these still run at a single speed, using the gears to gear down the motors speed (like a RC car transmission) or does it actually allow for different gearing for different conditions? Also, I read these are loud, which could kill my stealth approach. Worst of all I read they have nylon gears which are prone to stripping. Going back to RC cars, nylon gears were always a bad thing, and the fast/powerful cars ended up switching to all metal transmissions. So, perhaps geared hubs are not for me?

Being able to ride unassisted is a big deal to me. Even with the extra weight of the bike, maintaining some speed on the flats and pushing myself downhill unassisted is fairly high up on my priority list. It would also help me limp home if my electrical system gave out.

And, of course, I want to do this without breaking the bank. I realize it won't be cheap, but if it costs 5K it won't end up happening. A big part of what has me leaning toward Golden is the low cost.

So, all of that out of the way, what would you suggest/recommend?

Thanks,

Dan

 

[Dan K]

Allow me to ask a question I already think I know the answer to. You get what you pay for, so this has to be junk, right? http://largoscooters.com/wildernessenergy.html

If it’s even decent, I’m thinking it could be a way to get my feet wet without breaking the bank. Get it with the 12AH battery, and see how I like it. See how it pulls me around the hills, etc. If I dig it, then I buy a nice LiFePO4 battery pack for it. Then I buy a better wheel/controller/hub assembly, and that way upgrade piece by piece. It’d let me know if I was going to like this electric bike thing without breaking the bank. My concerns are this:
1) It’s too heavy.
2) Even with the 12AH battery, it’s not going to have any decent range at all. Obviously we wouldn’t have the 40 I’m looking for, but would it have 10?
3) Is it going to be weak, or is 600W basically 600W? The reason I ask is I wouldn’t want to be turned off from the whole thing thinking “if that’s all 36V & 300W gets me, this isn’t for me.” However, if that would give me a taste of what I’m in for, only on a heavier, lower quality and much lower range, it’d be a good way to get my feet wet. I could see saying “man, that was fun, too bad it’s dead at 8 miles.” Then I buy a battery. “Man, this is awesome, I wish I had a more powerful and more efficient motor, like a decent brushless”. Upgrade again.

So, this cheap-o system even going to give me a test ride, or am I throwing $ away? I could start at 400 and work my way into having spent thousands a whole lot easier than I can throw thousands at something to try it out, if that makes any sense.

Thanks,

Dan

 

[Drunkskunk]

Welcome to the forum.

Let me answer your second post first.
Thats a brushed motor. it has lead acid batteries.
Forget it.
You're familiar with RC, so I'm assuming you're familiar with brushless motors and there advantages. Brushed motors have no advantage anymore, they aren't even the cheapest.

Geared motors are single speed. They run a higher rpm motor through an internal gear set to drive the hub. The advantage is about half again more torque than the direct drive hub motor, and about 1/3 less weight. The disadvantage is 10 to 15% less efficiency at cursing speed, and noise. Geared hub motors are louder. Some sound like a pissed off drill on steroids, while others are so quiet you barely hear anything at cruising speed, and really only notice them when speeding up.

Gearless direct drive hub motors, on the other hand work like a ceiling fan, and the good ones only make as much noise as a ceiling fan. Some of them will hum , pur, or growl under heavy loads, but that goes away as the load eases up.

All of the major brands can handle getting dirty. But the best at wet resistance seems to be the 9 continents.

For what you want to do, the motors I would recomend would be
9 continents 9X7 36V
Crystalyte 408 48volt
Aetoma 48 volt (parent company of the Wildernes Energy Brushless version, also called the WE)

And for geared hubs, I would look at:
BMC 600 watt,
BMC 400 watt
Ezee 36v


In order to do 40 miles, your going to need something like a 48 volt, 20Ah battery. those don't come cheap, and you get what you pay for.

 

[Gordon]

Welcome to the forum.

...

Geared motors are single speed. They run a higher rpm motor through an internal gear set to drive the hub. The advantage is about half again more torque than the direct drive hub motor, and about 1/3 less weight. The disadvantage is 10 to 15% less efficiency at cursing speed, and noise. Geared hub motors are louder. Some sound like a pissed off drill on steroids, while others are so quiet you barely hear anything at cruising speed, and really only notice them when speeding up.
....

Cursing speed being ? Going down any hill and having a car cut you off :lol: Sorry, I couldn't resist.

I don't find my Ezee geared motor to be very noisy. It's a loud hum but it's really not annoying or noticeable, inless I go by you very close. It is very good on hills but I probably don't get the range you are looking for. It does have the advantage of being easy to pedal without using the motor. The hub itself also has a much smaller profile than the direct drive motors.

 

[dogman dan]

Heh Heh. Cursing speed would be about a half mile an hour, going up about a 15% grade?

You are on the right track with lifepo4, in my opinion, but don't have to have a123 for the smaller motors. Good vendors are Ebikekit.com, Hightekbikes.com, and for more flexibility on size and shape, pingbattery.com. I run a ping and love it. Of course if you have a place that gives away warrantee returned tool batteries, then A123! for free! It sounds like you have or could learn the skills to build a pack. The doc sells used cells also.

Lipo is up and coming too, for those with experience it can be very good and very affordable. But bigger packs, like 20 ah or more are just plain easier to charge with lifepo4. Plug it in, let the bms do the work, ride in the morning. The ready made packs come with cheap but easy to use chargers, custom home made lifepo4 packs can be a different story. Are you in canada? if so, its real hard to beat the yardworks tool packs from canadian tire.

On motors, if you really want to ride without using throttle, you do want a gearmotor. The ezee is one of the better ones. But us direct drive folks know that to ride with little resistance from the motor only take a tiny bit of throttle, so we don't mind doing that when we want to save power. I have a dd motor and a gearmotor, and there is no way the dd will coast like the gearmotor. So for sure, a gearmotor can hypermile better. You can power up to speed, coast a bit, then pedal some, and get unbelivable range with a gearmotor and strong legs. The gearmotors tend to be lighter too.

I have some of the Wilderness Eenergy type motors. The brushed hub is pretty lame, stay away from it. For the brushless version, High Tech Bikes is the source, and he offers a killer deal on a kit with lifepo4 battery, free shipping for es members. If a direct drive front hub is what you want, it's a good value. I like mine, and am trying unsucessfully to destruct test it. At full throttle, 23 mph, it will go 23 miles on a 36v 20 ah lifepo4.

Another front hub direct drive that is getting good reviews is the 9 continents from ebikes-ca See the epic topics in the general section to see what the owner of that shop has been up to.

 

[Dan K]

Welcome to the forum.

Let me answer your second post first.
Thats a brushed motor. it has lead acid batteries.
Forget it.
You're familiar with RC, so I'm assuming you're familiar with brushless motors and there advantages. Brushed motors have no advantage anymore, they aren't even the cheapest.

Yeah, I know RC and I know brushed is bad news. Ineffecient, brushes wear out, etc. In RC they’re no longer cheaper, but in that application they seemed to be. That’s why I was wondering if it’s enough to get my feet wet. I’d hate to shell out 4 figures on this and discover that it can barely get me up hill, the power isn’t there, etc. One of the reasons I was considering building a kit from RC stuff is I know I could overpower it insanely, with a very very efficient motor. It’s just too complicated and obvious a project that way. A rear hub motor under panniers is fairly stealty, which is what I want.

Geared motors are single speed. They run a higher rpm motor through an internal gear set to drive the hub. The advantage is about half again more torque than the direct drive hub motor, and about 1/3 less weight. The disadvantage is 10 to 15% less efficiency at cursing speed, and noise. Geared hub motors are louder. Some sound like a pissed off drill on steroids, while others are so quiet you barely hear anything at cruising speed, and really only notice them when speeding up

I think it’s the efficiency that will kill the geared thing for me. Noise as well, but it sounds like I could get a pretty quiet one. Still, it’ll be louder than a non-geared, and the big thing is efficiency. I’m looking for serious range, and losing 10-15% would be a serious detriment. OTOH, torque is nice. I’d really like to be able to get up hills, and do minor off roading (I won’t be climbing steep hills in the woods or anything, but smooth trails and rail trails will be at least 15% of my use). For this reason the Phoenix Brute appealed to me, but the range seems limited. Also, you need a 48V system just to hit 25MPH, with their test rider, who probably weighs 140lbs. I’m 180lbs.

Gearless direct drive hub motors, on the other hand work like a ceiling fan, and the good ones only make as much noise as a ceiling fan. Some of them will hum , pur, or growl under heavy loads, but that goes away as the load eases up.

Sounds like the way to go for me.

All of the major brands can handle getting dirty. But the best at wet resistance seems to be the 9 continents.

For what you want to do, the motors I would recomend would be
9 continents 9X7 36V
Crystalyte 408 48volt
Aetoma 48 volt (parent company of the Wildernes Energy Brushless version, also called the WE)

And for geared hubs, I would look at:
BMC 600 watt,
BMC 400 watt
Ezee 36v


In order to do 40 miles, your going to need something like a 48 volt, 20Ah battery. those don't come cheap, and you get what you pay for.

Thanks. I’ll check all of those out. I know the battery is not going to come cheap. If it gets me the range, power and speed I want it will be worth the $.

I notice that the first motor you suggested is the 9 continents 36V, but you’re saying I’ll need a 48V system for what I’m trying to do. What’s the big difference between 36 & 48? Obviously 48 is more volts, hence more power. Does this come with a higher amp draw and lower battery life? Alternatively, if I were to run a 36V & 48V system at the same speed, would they draw roughly the same amount of power, with the 48V just having more in reserve for when I need it?

Thank you for all the help and walking a newbie through this. I’m pretty set on building one of these things, but want to know as much as I can before dropping the $. The stuff can be expensive just to learn it does not do what I want.

 

[Dan K]

I don't find my Ezee geared motor to be very noisy. It's a loud hum but it's really not annoying or noticeable, inless I go by you very close. It is very good on hills but I probably don't get the range you are looking for. It does have the advantage of being easy to pedal without using the motor. The hub itself also has a much smaller profile than the direct drive motors.

Thanks for the reply. What kind of range do you get from your Ezee? I see from your sig you are using a 36V 15Ah LifePO. Also, how is the power? You said it climbs hills well, which is a bonus. Curious how far 15Ah woudl get me in a 36V system with enough torque to climb hills. Also, what is it's top speed?

Thanks,

Dan

 

[Dan K]

You are on the right track with lifepo4, in my opinion, but don't have to have a123 for the smaller motors. Good vendors are Ebikekit.com, Hightekbikes.com, and for more flexibility on size and shape, pingbattery.com. I run a ping and love it. Of course if you have a place that gives away warrantee returned tool batteries, then A123! for free! It sounds like you have or could learn the skills to build a pack. The doc sells used cells also.

I can build packs, but for this application, especially charging (I’d like to be able to charge at work without too much headache) I think a premade pack is the way to go.

Lipo is up and coming too, for those with experience it can be very good and very affordable. But bigger packs, like 20 ah or more are just plain easier to charge with lifepo4. Plug it in, let the bms do the work, ride in the morning. The ready made packs come with cheap but easy to use chargers, custom home made lifepo4 packs can be a different story. Are you in canada? if so, its real hard to beat the yardworks tool packs from canadian tire.

I’m quite familiar with LiPo, it’s all I use in my RC planes these days. Prettymuch gave up on the A123, now that I don’t crash often it’s not worth the extra weight for such a short run time. My 2.3Ah 9.9V A123 pack weighs twice what a 2.3Ah 11.1V LiPo weighs, and with the plane+camera only being a couple pounds the added weight really matters. I still have and occasionally use my A123 packs, but won’t buy or build another. I’m mainly running 2.5AH 11.1V LiPo on the plane now.

On motors, if you really want to ride without using throttle, you do want a gearmotor. The ezee is one of the better ones. But us direct drive folks know that to ride with little resistance from the motor only take a tiny bit of throttle, so we don't mind doing that when we want to save power. I have a dd motor and a gearmotor, and there is no way the dd will coast like the gearmotor. So for sure, a gearmotor can hypermile better. You can power up to speed, coast a bit, then pedal some, and get unbelivable range with a gearmotor and strong legs. The gearmotors tend to be lighter too.

My big concern with the gearmotor is the lack of range. I can learn to apply light throttle and pedal as well. I want to do this not only to save power but because I like the energy of riding. My intentions is to power in to work (no sweat, not arrive tired) and then get my workout in on the way home. I suppose if the gearmotor coasts that well, I might make up for the lack of efficiency by maintaining speed on downhills with my legs? If so, the gearmotor could be the way to go. Another concern is the nylon gears wearing out… how often does this happen?

I have some of the Wilderness Eenergy type motors. The brushed hub is pretty lame, stay away from it. For the brushless version, High Tech Bikes is the source, and he offers a killer deal on a kit with lifepo4 battery, free shipping for es members. If a direct drive front hub is what you want, it's a good value. I like mine, and am trying unsucessfully to destruct test it. At full throttle, 23 mph, it will go 23 miles on a 36v 20 ah lifepo4.

The High Tech Bikes sounds great, but there are 2 major problems. One is that 23 miles is not enough range. That’s from a 20Ah battery too, ouch! What am I going to need for a battery to get 40 miles? I could just buy two batteries. I planned on buying a second down the road anyway, but I was hoping to do that to extend my range to 80 miles, not to make my AM commute. I really don’t want to have to stop and change batteries en-route. With a top speed of 23MPH it’s a safe bet I’d be running it WOT the vast majority of the time. In R/C, the A123 packs can take a charge about as fast as we can throw one at them. Some guys are direct charging larger packs off of car batteries, less than an hour for a good sized pack. How long does it take to charge a 20Ah LiFePO4 with the supplied charger?

Another front hub direct drive that is getting good reviews is the 9 continents from ebikes-ca See the epic topics in the general section to see what the owner of that shop has been up to.

I’m pretty sold on a rear hub. I want to be able to conceal it with panniers. I also think I’d be more comfortable with the power pushing me than pulling me, since I ride motorcycles and dirt bikes.

Thanks for your help!

Dan

 

[Dan K]

OK, so I’ve done some poking around on the suggested products.

It seems I can get an ezee, sans battery and charger, for $750. Not sure what the battery and charger would set me back. Not cheap by any means, certainly a lot more than the other stuff I was looking at, but if it’s going to give me what I am looking for it’s worth note. They also say that although normally sold with 36V systems, the new controllers are good for 24-48V batteries. A custom LVC can be set through the included cycle analyst, which is a bonus if I were to go to 48V. I still worry about range, if a 20Ah 36V LiFePO4 is only getting 23 miles @ 23MPH.

On to the BMC. I’m wary of the 400W version, as I’ve heard a few times now that anything that low wattage is lacking. The 600W BMC “Thunderbolt” complete kit looks very tempting, but I have some doubts in their numbers. Also, all their kits come with LiPo batteries, but they sell some tempting LiFePO4 batteries. I’m going to call them today to get a feel for if I can get a kit with a LiFePO4 rather than a LiPo, what cost would be and what motor and conditions their suggested ratings are. They claim 60 miles from their 51.2V 20AH LiFePo4! They also claim 43 miles from their 36V 20AH LiFePo4. If the 36V pack is enough (which it may be, considering this is a geared setup) that may be the way to go. Again, a big problem is that it’s a front wheel system. I’m not ruling it out, but I’m still looking.

I looked at e-bikekit, but they seem to only have 500W 36V systems, and the kits are all with small batteries.

Hitekbikes.com seems to have a decent 750 watt system. Again, the included batteries are lacking, but @ $330 for the motor kit, I can supply my own battery and charger.

A couple more questions, if I could.

1) Any suggested sources for buying batteries and chargers separately from the motor kits?
2) It seems all chargers supplied with the LiFePo4 batteries are 2A. Why is this? It’s my understanding LiFePo4 can take a much faster charge than 2A, well into the double digits in fact. @ 2A I’m looking @ a 10hr charge for a 20AH battery.

Thanks again!

Dan

 

[BVH]

I, too, am mystified why so many LifePo4 chargers are charging at a .1C and .2C rate? In the DeWalt 36 Volt tool packs, they're being charged at 4C with good results.

 

[Dan K]

OK, so I've done a bunch more looking around and thinking. I think my best bet will be to buy my batteries and charger separately, so I can choose battery size and a charger that will allow me to charge a 20AH battery in less than 10 hours. Once I find a good source for LiFePo4s and chargers, that is. the 2A charge is just unacceptable to me. My $50 R/C charger can charge lipo and A123 at up to 4A. There's no reason to be charging such a large pack @ 2A.

The BMC 600 looks really good. All reviews say it's quiet, it seems to have plenty of power, overall I like it. The problem is, I can only find the 600 as a front hub! I am concerned the 400W will lack the power I want. Tests show it has more than enough top speed, but I'm worried about the hills and being off pavement. Also, I've decided against buying a less expensive motor as a temporary stopgap. I'm going to spend the $ and do it right. This means rear wheel drive. I'm simply not comfortable with a front wheel drive, for both esthetic reasons and because I am more comfortable with RWD due to dirt bike and motorcycle experience. If I'm going to lose traction in the dirt, I want it to be the rear wheel that breaks free. Any similar alternatives I should know about in RWD?

 

[Drunkskunk]

After reading your responses, I figured I'd add some info on how this all works out.

Voltage gives speed. the higher the voltage, the higher the speed.
Amperage gives torque, so the higher the amperage, the harder you will accelerate and better you will climb hills.
Wattage is Amps X Volts. Higher voltage needs lower Amperage to get the same wattage.


Motor wattage in Ebikes isn't like in RC. a 500 watt RC plane motor is hitting it's peak at 500 watts. a 500 watt bike motor cruises at 500 watts at full speed and normal voltage, but will peak much higher, and sustain much higher if pushed. I run my 500 watt motor at 3000 watts under acceleration. At cruising speed its commonly above 800 watts. I've been doing that for a 1000 miles. I outrun and embarrass mopeds with my 500 watt motor, but I run it at higher than normal voltage. Not something I recommend starting with, but the potential is there.

Not all motors react the same to voltage. A 9 continent 9X7 will run around the same speed at 36V as a Clyte 408 at 48V, but the 9C will need to pull more amps. the wattage will be about the same. And for geared motors, they make so much more torque, that they don't need the wattage to make the same output for acceleration.

 

[Dan K]

Current options:

BMC 600W Rear Hub w/ motor, controller, throttle.

After reading your responses, I figured I'd add some info on how this all works out.

Voltage gives speed. the higher the voltage, the higher the speed.
Amperage gives torque, so the higher the amperage, the harder you will accelerate and better you will climb hills.
Wattage is Amps X Volts. Higher voltage needs lower Amperage to get the same wattage.


Motor wattage in Ebikes isn't like in RC. a 500 watt RC plane motor is hitting it's peak at 500 watts. a 500 watt bike motor cruises at 500 watts at full speed and normal voltage, but will peak much higher, and sustain much higher if pushed. I run my 500 watt motor at 3000 watts under acceleration. At cruising speed its commonly above 800 watts. I've been doing that for a 1000 miles. I outrun and embarrass mopeds with my 500 watt motor, but I run it at higher than normal voltage. Not something I recommend starting with, but the potential is there.

Not all motors react the same to voltage. A 9 continent 9X7 will run around the same speed at 36V as a Clyte 408 at 48V, but the 9C will need to pull more amps. the wattage will be about the same. And for geared motors, they make so much more torque, that they don't need the wattage to make the same output for acceleration.

Thanks, that is very helpful! Now it’s all starting to come together. Everything I’m looking at provides plenty of speed. That said, maybe 36V would be enough for my application? It seems that would still push me to 25MPH with most kits I’m looking at, and the controller is what decides how many amps to let at it, right? In fact, with a lower voltage battery I’d be able to draw more amps before hitting the max watts, but from what you’re telling me max watts isn’t much of an issue since most of these can be pushed well beyond their “named” wattage.

I also made a mistake in my earlier post, although many retailers do not have the 600W BMC in rear hub, it is available from some.

The 9 continents seem to be direct drive. The more I learn, the more I lean toward geared, which unfortunately leaves them out.

 

[dogman dan]

Keep reading, you are getting the picture. I wish I'd seen this fourum before I decided to buy cheap brushed hubs for my first buy.

On the range thing... you want range, you want speed. You sound like the ads of some vendors. " it will go 20 miles on a set of 12 ah sla's , top speed is 25 mph. Notice they didn't say 20 miles AT 25 mph.

Range wise, 23 miles at full throttle isn't so bad. If you get a 48v 20 ah pingbattery you will have a better top speed and still go 20-25 miles at full throttle unless you are over 200 pounds. I also ride a commuter bike, so it's got stuff strapped all over it, and tall handlbars. So I'm sitting up tall and mabye have a coat flapping in the wind. Not exactly your best mileage configuration. When I test the range on my bike, I ride full throtte, and climb a 500 vertical hill along the way, so it's a pretty realistic test. The other day I rode 1500 vertical feet uphill, into about 5-10 mph wind at 12-15 mph and went 28 miles. Most of the ride was at 3/4 throttle. The only way to get fantastic range is to pedal a lot, coast a lot, and go slow. That's where the gearmotor suggestion comes in. The freewheel lets you coast more, so you will get amazing range if the throttle is only used on the uphill parts. But this is not riding fast, it's riding normal bike speed, and using the motor just to get up hills.

But the bottom line is, if you want to go 40 miles at fast speed, you are going to have a 40 ah battery. Two 48v pingbattey 20ah packs will weigh 44 pounds, or about the same as a 48v sla pack. It's a lot of battery but the weight is doable. You can get a higher amp charger for a bit more money than the usual 2 amp. I can charge my 36v 20 ah ping with a 3 amp charger in about 8 hours. or 12 hours with the 2 amp. I think you can now get a 5 amp charger, so about a 6 hour charge? You can charge faster, but not through the bms. I suppose you could do a 20 amp for 45 minuites, and finish through the bms, but you would risk overcharging it.

There are almost too many options out there. But many of the competing motors are pretty similar, and you end up buying from the vendor you like best.
You have three main decisions, Geared or direct drive, front hub or rear, and what battery. If I were you, I'd decide how much speed I was looking for. If much over 25 mph, then the decisions get real easy, Chrystalyte 530x motor, and you have to build your own pack for voltage over 48v. If 25 mph or so is fast enough, pick a reputable vendor for a lifepo4 pack, and a motor that runs at a speed you like. Ride it some, and then decide how much range you really need, 40 mile range is a lot for commuting. But for touring, it may be real nice to have that much. Personally, I find my 15 mile commute to be about the max I'd want to do on a bike.

 

[Dan K]

Dogman,

Thanks for the reply. As far as speed, I’m fine w/ 25MPH. I’ll probably cruise around 20, since that’s the supposed legal limit (although I pedal faster than that, so I doubt I’d get bothered for going a hair over, especially if they can’t tell it’s electric <G>

Sounds like ping is the way to go for the battery? He actually sells a 48V 40AH LiFePo4 pack that weighs 20lbs, for $725 once it’s shipped. That could very well be the ticket, but if it still won’t give me the 40 miles I still have an issue. It comes with a 2A charger, but that will just take too long. The specs on the battery say it needs to be charged <5A (I have no idea why this is, the A123 cells in RC can handle brutally fast charges). If I could charge @ 5A and charge it in 6 hours, that would work. It would at least allow it to recharge while I was at work.

Ecrater.com has a 40Ah 48V that can charge < 8A for $722, basically the same $ as ping, but it’s a vendor I’ve never heard of. It’s also 27lbs as opposed to 20lbs.

Cammy_cc on ebay has a 48V 40Ah pack with a 5A charger for $500, shipped. That sure is tempting, but again I don’t know the vendor. They do point out in their ad something I’ve read elsewhere, which is that many chargers do not charge at the rate they claim. They show theirs showing 5.23A in charge on a multi meter and say that you can return it for a full refund it does not live up to expectations. Also comes with a warranty. Big downside to that one seems to be that it’s 32lbs, rather than 20. If it were a good pack, the free 5A charger and the $225 less it costs would make up for the extra weight, IMO. All reviews are positive except people complaining about shipping time, which is to be expected with anything coming from china that is not shipped express. Learned that with RC.

At this point the battery is a tough call. The ebay battery looks good, the reviews are positive, it comes with a 5A charger and is $225 less than ping.

I’m definitely getting hit with the “too many options” thing.

As for my decisions:
Geared. I want the torque for the hill climbs, and the ability to freewheel.
Rear hub. This is for comfort in my riding as well as being able to hide most of it under panniers.
Battery… 48V 40Ah seems like my only option. Not cheap @ $750, but there isn’t much that can be done about that.

I hear you on 40 miles seeming like a lot, but it’s not an optional thing. My commute is 35 miles each way, and since the batteries lag a touch with use I want a little overhead. Right now I usually take the bus most of the way in, and ride back home. I don’t want to pedal in, because I’ll arrive tired and sweaty.

 

[Dan K]

I have some of the Wilderness Eenergy type motors. The brushed hub is pretty lame, stay away from it. For the brushless version, High Tech Bikes is the source, and he offers a killer deal on a kit with lifepo4 battery, free shipping for es members. If a direct drive front hub is what you want, it's a good value. I like mine, and am trying unsucessfully to destruct test it. At full throttle, 23 mph, it will go 23 miles on a 36v 20 ah lifepo4.

As much as I don't really want a front hub, nor a direct drive, I've got to ask here and it just may make my list. If this will do 23MPH, WOT, for 23 miles with a 36V 20Ah LiFePo4, what would it do with a 48V 20Ah LiFePo4? If I kept the speed around 23MPH, it should use about the same amount of juice, right? So would that give me 40+ mile range, with a little extra oomph in reserve?

Also, I assume you are talking about www.hightekbikes.com? $329 for a 700C wheel, 750W motor, controller, throttle, rack and bag sure is tempting. Throw in that ebay battery and for $830 I’m rolling. Well, once I convert one of my many bikes, which I can probably do for nothing.

Edit: How do you go about getting the free shipping for E-S members?

 

[Dan K]

I think I'm going to do either the hitekbikes wheel, to save some $ for now and get a taste, or just bite the bullet and buy BMC 600W. One thing I'm not sure of is if I'd want the BMC high torque, or high speed. The high torque only gives #'s @ 72V, no idea how it will perform @ 48V. The high speed will give me more than enough speed, the question is will it have enough torque. General concensus seems to be that the geared motors all have enough torque?

I think I'm sold on the cammy_cc battery. 48V 40Ah LiFePo4 with a 5A charger for $500.

Then I have to decide:
High tek bikes front drive hub. $329 with motor, 700C wheel, controller, throttle, rack and battery bag. One poster gets 23 miles @ WOT 23MPH w/ a 20AH 36V LiFePo4. Looks pretty darn good, and very affordable. Downside: It's FWD, and direct drive, so no coasting. I suppose I can do the touch of throttle to eliminate drag trick, and if it can do 23 miles @ 23MPH on a 20Ah pack I should be able to get my 40 miles on a 40Ah pack if I'm easy on the throttle, no? I'd probably upgrade it down the road, but it would let me get started a lot sooner.

The other option is biting the bullet and buying the BMC 600W. Still not sure high speed or high torque. Either way it's going to be $962 before shipping, so probably well over a grand for the motor, controller, throttle, wiring harness and freewheel. The good thing is it's a plug and play solution, and exactly what I want. The downside is it pushes my project over $1500, which will slow down it actually happening. Tempted to buy the high tek for now, and the BMC later.

Any suggestion, advice, anything I'm missing, something else that should be in real contention, please let me know.

Thanks,

Dan

 

[dogman dan]

Ok, at 20 mph you will get a bit more range, and you won't need to choose a particualr motor to get speed. For more info on the Hightekbikes motor, I have a long thread going on the review section, as well as a pingbattery thread. When I like something I like to let the world know, too much of the forum is aimed at fixing a problem or bashing a vendor or product, with little posted on what did work. Anyway, I have found the aotema brusless motor a good commuter. I don't know your climate, but I have found some issues with heat building up on a long ride. With a thermometer in the hub, I now know when on my ride to slow down. It may not matter to you, but I live in the desert, and my ride home is all uphill. One of my gripes with the brushed motors is that they run hot compared to brushless.

Your ride home of 35 miles is a whole different animal than trying to get to work on time, riding in 35 miles. If you need to ride slower, it can be done, unlike the time pressure on the way TO work. I was seeing trying to do a days work and ride 80 miles, Whew! That would be hard for me! At 20 mph you might get 25 miles out of the same pack as mine, and a 48v 20 ah will be 25% bigger, so perhaps 30 miles wouldn't be very hard to do reliably.

Ping can also suppy you with a 5 amp charger. Cammy is right about chargers, my 4 amp, actually puts out closer to 3 amps. Lots of 2 amp chargers only do 1.5. Ping can make you a bigger battery too, you just have to email him and ask for what you need. His good reputation is partly based on this ablility to do custom stuff. He can make it in two pieces so you can carry easier, etc. A 48v 25 ah might just be big enough, or the option I would choose, two 15 ah packs and two chargers. Then paralell connect em. That way two chargers can be used.

Cammy cc has a good reputation with customer service so if you want to spend less on a 18650 round cell pack, that is the vendor to choose. Others come and go, and one has too many selling names to keep track of. With the round cells, there are so many cells, like 140 or more in a 48v pack, where pings have 80 cells in a 48v pack of the same size. On the round cells, the pack is made with spot welded connectinc strips, while the pouch cells ping uses are soldered. The tabs on the pouch type can tear, but not as easy as the spot welds can pop. A lot of packs get damaged by the shipper with the spot welds. The thing falls off a conveyor, and poing. There are many other options, but for what you need, either cammy or ping may be the easiest to choose from. But if you are buying a motor from High tech, ask terry about a package deal on two 15 ah packs, and a motor.

To get the free shipping deal on High Tech bikes, look for Terry in the for sale section, and then Personal Message him. If you are going to buy, he will send you a special link that pays for the purchase with no shipping charge. Terry is an ok vendor, and his lifepo4 battery is the equal of a ping.

Your goal of 40 mile range is doable, it's just a question of riding a bit slower or buying a bit more battery. Different size batteries of the same voltage can be paralelled, so it wouldn't be so bad to buy a 20 ah pack , and add a 10 later if needed.

 

[dogman dan]

You got another one in while I typed. On the subject of torque, is there a particular reason you need torque, other than it's fun? I want the bmc too, but for a dirt bike to ride single track, steep as hell trails with. For my commute, which includes a hill with some 6% grade, and a mile of 5% my aotema flys up it and that is at a mere 36v. Unless your ride has serious hills, most any direct drive motor will have sufficient torque to get you going. I have climbed some 10% hills with the aotema, but I find it can handle a lot more, if you really slow down. In the lowest gear, with just a tiny bit of throttle, you can climb really steep hills but with lots of pedaling. The trick is to not stall the motor by putting more power in it than it can use at such slow speed. It's weird, totally counter to what you think would work, but it does get you up steep hills with pedaling that is still easy to sustain.

 

[dogman dan]

Just one more, I forgot about the charge rate thing. The bms is what limits the commonly avaliable batteries to 5 amps. Bypassing the bms to charge can be done, but it's risky, you might overcharge if you don't stop it in time. I'd love a 20 amp charger for a quick partial charge en route, but in that size , a charger might be harder to carry than a second battery. If you do a stop on the way home, like dinner, a split pack with two 5 amp chargers going would get a noticable range extension for a half hour stop.

 

[Dan K]

Ok, at 20 mph you will get a bit more range, and you won't need to choose a particualr motor to get speed. For more info on the Hightekbikes motor, I have a long thread going on the review section, as well as a pingbattery thread. When I like something I like to let the world know, too much of the forum is aimed at fixing a problem or bashing a vendor or product, with little posted on what did work. Anyway, I have found the aotema brusless motor a good commuter. I don't know your climate, but I have found some issues with heat building up on a long ride. With a thermometer in the hub, I now know when on my ride to slow down. It may not matter to you, but I live in the desert, and my ride home is all uphill. One of my gripes with the brushed motors is that they run hot compared to brushless.

Sweet. I read your review thread, and it was very helpful. I live in New England. It gets hot, but not desert hot. We have hills, but I don’t have anything like you describe in my intended rides. There’s the white mountains, but I’d only go there on a pleasure bike and it would be my road bike, not the e-bike. This is for commuting and maybe visiting semi-local friends.

Your ride home of 35 miles is a whole different animal than trying to get to work on time, riding in 35 miles. If you need to ride slower, it can be done, unlike the time pressure on the way TO work. I was seeing trying to do a days work and ride 80 miles, Whew! That would be hard for me! At 20 mph you might get 25 miles out of the same pack as mine, and a 48v 20 ah will be 25% bigger, so perhaps 30 miles wouldn't be very hard to do reliably.

This is all good insight. Sounds like 40AH with that motor would do me just fine.

Ping can also suppy you with a 5 amp charger. Cammy is right about chargers, my 4 amp, actually puts out closer to 3 amps. Lots of 2 amp chargers only do 1.5. Ping can make you a bigger battery too, you just have to email him and ask for what you need. His good reputation is partly based on this ablility to do custom stuff. He can make it in two pieces so you can carry easier, etc. A 48v 25 ah might just be big enough, or the option I would choose, two 15 ah packs and two chargers. Then paralell connect em. That way two chargers can be used.

I’d still be concerned with overall range. I want as much as I can get, so I’m going to go 40Ah. I thought about doing to 20Ah packs, but it would cost quite a bit more than a single 40Ah. The dual charger thing is a nice thought though, so I’ll reconsider the dual 20Ah batteries. It would even the weight in the panniers more as well, which is a bonus.

Cammy cc has a good reputation with customer service so if you want to spend less on a 18650 round cell pack, that is the vendor to choose. Others come and go, and one has too many selling names to keep track of. With the round cells, there are so many cells, like 140 or more in a 48v pack, where pings have 80 cells in a 48v pack of the same size. On the round cells, the pack is made with spot welded connectinc strips, while the pouch cells ping uses are soldered. The tabs on the pouch type can tear, but not as easy as the spot welds can pop. A lot of packs get damaged by the shipper with the spot welds. The thing falls off a conveyor, and poing. There are many other options, but for what you need, either cammy or ping may be the easiest to choose from. But if you are buying a motor from High tech, ask terry about a package deal on two 15 ah packs, and a motor.

Sounds like Cammy is what I need for a battery. I am set on 40Ah though. I can ask Terry about a package deal on two 20Ah packs and a motor. His charger is still 2A though, and from what I’ve read they take even longer than simple math would lead you to believe, balancing and such. A big selling point for me using Cammy is that 5A charger. 2 48V 20Ah packs with 2 5A chargers would be sweet, I’ll have to see what I can get and how it effects cost and overall weight. Still, I’ll see what Terry has to offer.

To get the free shipping deal on High Tech bikes, look for Terry in the for sale section, and then Personal Message him. If you are going to buy, he will send you a special link that pays for the purchase with no shipping charge. Terry is an ok vendor, and his lifepo4 battery is the equal of a ping.

Awesome. Thanks for the heads up. Do you know Terrys user name on here? I did a quick search and came up empty handed.

Your goal of 40 mile range is doable, it's just a question of riding a bit slower or buying a bit more battery. Different size batteries of the same voltage can be paralelled, so it wouldn't be so bad to buy a 20 ah pack , and add a 10 later if needed.

Again, thanks for all your help. You’ve been hugely helpful on this entire subject.

 

[Dan K]

You got another one in while I typed. On the subject of torque, is there a particular reason you need torque, other than it's fun? I want the bmc too, but for a dirt bike to ride single track, steep as hell trails with. For my commute, which includes a hill with some 6% grade, and a mile of 5% my aotema flys up it and that is at a mere 36v. Unless your ride has serious hills, most any direct drive motor will have sufficient torque to get you going. I have climbed some 10% hills with the aotema, but I find it can handle a lot more, if you really slow down. In the lowest gear, with just a tiny bit of throttle, you can climb really steep hills but with lots of pedaling. The trick is to not stall the motor by putting more power in it than it can use at such slow speed. It's weird, totally counter to what you think would work, but it does get you up steep hills with pedaling that is still easy to sustain.

I only wanted the torque for hills, acceleration and mild off-roading. Not insane stuff like I do on my MTBs, just trails that are alternative to roads. From what I gather, the aotema will be more than enough.

 

[Dan K]

Just one more, I forgot about the charge rate thing. The bms is what limits the commonly avaliable batteries to 5 amps. Bypassing the bms to charge can be done, but it's risky, you might overcharge if you don't stop it in time. I'd love a 20 amp charger for a quick partial charge en route, but in that size , a charger might be harder to carry than a second battery. If you do a stop on the way home, like dinner, a split pack with two 5 amp chargers going would get a noticable range extension for a half hour stop.

Sounds like the split pack thing would be the ticket, especially with 2 chargers. I have 5A RC chargers that are very small, but nothing that can handle that many cells. Buying a much bigger charger is probably overkill, if I can charge at a true 5A with split packs, allowing me to get 10A in an hour, that'll be fine. Once again, thanks so much for your help. Sounds like the motor from Terry is the ticket. I wanted rear wheel drive, but for the cost difference it's not worth it. Especially with direct drive being more effecient. I can lay on a dab of throttle to pedal and coast downhill. Saving a ton of $ over the BMC is a nice touch as well.

 

[Drunkskunk]

With your goal of 40 miles, I would steer clear of the BMC 600.
Its true it does offer better torque, but at a cost of range.

The Clyte and the Aetoma are very similar motors. the older Aetoma compared to a 408, I think Dogman's and some of the newers would compare better to the 407 in terms of speed and torque. The 9C motors make more torque than the smaller sized Aetoma and Crystalytes, and they have a slightly higher efficancy. But they also have a narrow spoke mount, and I wouldn't want too much side load on one. So trail riding, at least for mine, is out.

If you want some trail use and long cruising capability, then the Clytes and the Aetoma are the best motors.

The Aetoma comes in only one type. if it is in your speed range then its a good match. And I think it very well may be.
The Crystalyte 40X series comes in a large selection of motors. the 40 in a 408 motor means a 40mm magnet, the 8 is the number of windings. I'm sure you understand winding count from RC motors, he higher the number of windings, the slower the motor. What doesn't come up in RC much is peak efficiency. the closer your top speed is to your desired cruising speed, the more efficient you are. With Clyte motors, you can pick from a 404, 405, 406, 407, 408, 409, 4011 (yeah, no 4010) 4012, and 4013. the 408 is the generic default as it Preforms best in the low to mid twenties. But then there are alternatives, Such as running a 4012 at 74 volts (20s2p lipo) to get 26mph top speed but huge torque from a small package.

there is a tool at http://ebikes.ca/simulator/ that will let you setup diffrent motors, voltages, wheel sizes, amp limits, ect. Its notoriously Accurate and many of us here have found it reflects near exactly what we get on the road so it's not just some vendor hype. the thing to remember when reading it is the top motor speed is unladen, and to find your true speed you need to look at the blue line (thrust) Its similar to plane thrust. when you reach a certian point, you can't go any faster. its different for every person, but for me, its roughly 7 pounds to go 20mph, 10 pounds needed to go 25mph. and 17 to go 35mph

 

[davespicer]

The trick is to not stall the motor by putting more power in it than it can use at such slow speed. It's weird, totally counter to what you think would work, but it does get you up steep hills with pedaling that is still easy to sustain.

Cool! I'll have to try that with my BL36

There sure are a lot of variables to consider... "throttle opening" wasn't one I had thought about. We could use someone on the forum with a small dynamometer to run bunches of tests and chart the results - in this case, torque/thrust vs throttle amount at low speed. Um, while also tracking motor temperature, and watt-hours used, and... wait. How many axes/dimensions can a chart have? We're gonna end up charting in hyperspace