School me on hub drives

[sharp21]

I've been doing a ton of reading about the various ebike options but am still a little in the dark. I'm just going to put a few questions out there...

For what application would you select a front hub drive over a rear?

What application for fixed vs geared?

I know with golf carts the way the motor is wound limits the speed. Thats why if you run a 36v motor through a 48v controller you get a higher top speed. Is it the same with hub motors? If I bought a 36v kit from, say Amped Bikes, how far can you overclock them?

Last, would I be better going with a kit, or sourcing my own from various vendors? I'd like 30mph+ on the speed with the ability to upgrade past that later. Who is making the highest powered, most reliable components?

Thanks!
S.

 

[spinningmagnets]

Welcome to ES. Buy the battery and the charger from the same company...buy the hub, throttle, and the controller from the same company so the plugs all match.

Front hub is an easier install over the rear, but if you want 30-MPH, it will stress the front forks and many bikes don't have steel drop-outs on the front. If you hot-rod it, a rear failure is less lethal than a front failure (faceplant at 30-MPH).

Get two torque-arms regardless of what other parts you get, they are cheap...just do it.

Front hub has 2WD in slippery conditions, but slips some on steep uphills (when you want E-power most). Ive heard good things about the 9C, Aotema, and the Amped-Bikes geared hub (Haven't ridden any of them). Geared are smaller and lighter (more stealthy) but louder under acceleration, DD-hubs are clearly more visually obvious (bigger) and heavier, but they are so simple, many consider them to probably be the most reliable when used at their stock performance.

All the geared hubs I've read about can be upgraded from 36V to 48V, but any higher volts than that, I recommend a DD-hub (60V+). Many DD-hubs are near-silent. 20-MPH is the federal limit for an unlicensed/unregistered electric moped, so most kits are sold to the public with a winding that will do 20-MPH at 36V. 48V is an easy customer-implemented upgrade for higher speed (27-ish, the companies know this).

Some E-bikers who wanted a smaller geared hub ran them at 60V to get near 30-MPH. They had very good hill-climbing torque, but frequent hills build up heat, and the plastic planet-gears inside them act as a mechanical fuse (search peanut-butter Bafang).

My opinion? Get a bike that is comfortable for you with front suspension, fat tires, and a front disc brake. There are affordable suspension-forks that can be bought that will fit onto an aluminum beach-cruiser frame if you don't like the standard posture. Used MTBs that were $500 new are sold every month on Craigslist for $200. Get the DD rear-hub that will satisfy your end goals (it should last decades).

Your specs sound like a rear 9-Continents (search 9C) at 48V/60V. You will only need a single large front chainring (52T), and 5 or 6 gears in the back.

If you have a limited budget, get a 36V Sealed-Lead-Acid battery pack (SLA, don't laugh). They are cheap and after 6 months when the pack wears out...that is just about enough time to save up for the 60V lithium pack (doctorbass...soldering iron) and controller that will last a very long time and do what you want.

The three big expenses are the bike, the motor/controller kit, and the battery. If you can afford to upgrade all three, great. If you can't, decide which one of the three you're willing to compromise on now, and upgrade later.

 

[spinningmagnets]

I don't mean to post so much, but....this is coming up on a regular basis, so its good to post the definitive results of extensive search from the archives. Here's my 9C blurbs...

"...Doctorbass's E-bike recommendation:
9 continents, and I recommend the 12 mosfets 4110 infineon programmable controller, it's great powerfull simple and cheap. As for the battery, the Ping 48V 15Ah is always a great option, and that's the component that will limit the power... around 2500W peak and 2000W continuous. For the charger the Ping 5A 48V aluminum case is the best option. Charge in 4 hours, cheap, small, and strong.
That kit of around $1200 and everyone can do 50km (30 miles), 52kmh (32-mph) and go uphill to about 30kmh

Dogmans ebike suggestions:
Fast aint cheap, but it can be done fairly cheap for a 4-5 mile ride.
9 continent 2807 or 2806 rear hub motor. Around $250-300 shipped.
Lyens 12 fet controller and throttle. Around $150-250 shipped. Higher price for more fets and voltage.
72v 5 ah lipo battery and charger. $350-400
Learning curve. $500-1000. Starting out with this much power, it's quite likely you will ruin bikes, motors, etc in the first 50 feet of ride. When the motor twists itself right out of the bike on the first ride, it gets expensive. You will also screw up some batteries. This part can be avoided mostly, if you read enough build threads about torque arms and what frame to choose, and PAY ATTENTION.
For more miles, the ante is about $250 -300 for each 5 ah more battery. Battery is where the real money is, for going fast. Stock 9c kits on 48v go 27 mph though. Much cheaper to aim for 30 mph.
Lyens controllers in the for sale section, Batteries from Hobby King, 9c motors from either ebikes-ca or e-bikekit..."

Edit: I'm told the 9C on 72V is a beast, and much cheaper/lighter than the Crystalyte 530X-series (which is almost a moped/scooter motor), plus controllers for over 72V are much more expensive. Not many people using 60-ish volts, save info gathered on 48V and 72V for the performance you are looking for...

 

[Drunkskunk]

+1 to what Spinning magnets wrote.

The front VS rear debate is ongoing. Most agree a rear motor is best for a cargo bike or when the bike has an aluminum fork or for riding on loose terrain. But for an average commuter bike on established roads or trails a front motor is a easier solution. A front motor can also help shift the weight forward on the bike, better balancing the bike. Ultimatly, its a matter of personal taste, though.

Geared hubs make better starting torque, weigh less, and accellerate more efficently than direct drive motors. but they have less mass to absorb heat, and the gearing can suffer from abuse

Direct drive are heavier, quieter, and can absorb and disapate many times more heat. They're more efficent at cruising speed, and with only 1 moving part, they can handle far more abuse.

Most of the direct drive motors thrive on higher voltages. not every controller can handle higher voltages as well as others, and for some, you'll need to modify various parts. However, motors like the 9C (Nine Continents) and the various Crystalytes, Aetomas, and 1st gen GMs realy come alive in the 48 to 72 volt range. 100 volts isn't a problem for most of them. the limit realy is the controller

The internal geared motors can handle some higher voltages, but not to the extream. 12 volts over is fine for most of them, but going beyond that is risky

 

[sharp21]

Thanks guys. The learning curve is pretty steep & there is a lot of digging through posts required to get the big picture.

So the 9c motor sounds great! I've read some about the Crystalite motor as well, as the high power offering. What is the difference between the two? The other big motor I've come across is BMC.

So a DD will be heavier & wont freewheel, but it can be over volted easier for bigger speed. The geared has more low end torque but can't be volted much past its rated voltage. If you want a geared hub + the big speed you need to pony up for a big 9c, Crystalite or BMC.

Arent the 9c motors the same as Amped bikes? Theirs was the first kit I was considering.

Here is a great page comparing various hub drives:
http://www.electric-bikes.com/bikes/kits.html

S.

 

[spinningmagnets]

Nothing wrong with the Crystalyte 530X-series, but they are heavier and more expensive than the 9C.

edit: if you were going to go 40-MPH, the Clyte 530X would be my first choice. Not only can it take the power needed and dissipate the heat, but it is stronger, so when you hit a pothole at 40-mph it can take the abuse, you're more likely to break a spoke. At 30-mph, (which is pretty fast for a bike), it just didn't seem to be worth the extra expense. Also when just cruising around town, I've been given the impression that the 530X will suck your battery dry pretty fast...

I have not owned or ridden either one.

 

[John in CR]

For more speed later invest in the X5 up front, so all you have to do is go up in voltage. I'd suggest the X5304, because the 5303 is very hard on controllers, that is unless you live where the roads are quite flat and you're not a fatty like me. To get the kind of power it sounds like you will eventually go to, a 9C simply isn't going to cut it without drilling holes in the covers for centrifugal ventilation, but that opens the motor up somewhat to the elements. One 9C now with an upgrade path of adding another 9C and upping voltage later is a viable alternative, but the extra motor and controller is likely to cost more than the X5 plus one controller.

Planning ahead goes for the controller too. Get a variable voltage controller, so you can start at 48V (needed for 30mph) and later go to 72V or 84V. Connections aren't that big a concern, because the stock ones are crap anyway, though stuff from Ebikes.ca may be an exception. Sourcing best prices different places is a non-issue to me, and only a problem if you really need plug and play.

Fast ebikes need good brakes. Regen is a big help and reduces use of the regular brakes. If you want low maintenance on the brakes then regen braking plus hydraulic disk brakes is the only way to go.

Going fast on a normal upright bike is a matter of taste. Some accept it, but the high center of gravity and short wheelbase was too much for me. I modded a mountain bike frame to be longer and lower, and now I'm perfectly comfortable now at 50-60mph. OTOH the little dual suspension bike I have that does almost the same speeds (lower due to greater wind resistance) is like an amusement park ride, thrilling and scary.

John

 

[Drunkskunk]

Thanks guys. The learning curve is pretty steep & there is a lot of digging through posts required to get the big picture.

So the 9c motor sounds great! I've read some about the Crystalite motor as well, as the high power offering. What is the difference between the two? The other big motor I've come across is BMC.

So a DD will be heavier & wont freewheel, but it can be over volted easier for bigger speed. The geared has more low end torque but can't be volted much past its rated voltage. If you want a geared hub + the big speed you need to pony up for a big 9c, Crystalite or BMC.

Arent the 9c motors the same as Amped bikes? Theirs was the first kit I was considering.

Here is a great page comparing various hub drives:
http://www.electric-bikes.com/bikes/kits.html

S.

Yeah, its got a bit of a steep learning curve on it.

The BMC is a geared motor, were the Clytes and the 9C are direct drive motors.
Crystalyte makes a 500watt motor called the 40X, were the x denotes the winding count. a higher number being slower. (404 through 4013) they are 15lbs motors, and take being pushed to high wattage fairly well. They also make the 750 watt series refered to as the 530X series (5302 through 5306) , weighing in at 25 pounds. these motors are the kings of abuse, but very heavy, and are wasted when run at their normaly rated power.
9C are 500 watt motors, weighing just 12 lbs. they can't technicly take as much abuse as the 40X, but the larger diameter means they make better torque, and they still take plenty of punishment. they have 2 naming conventions, being called 280X, were the X has the same meaning as the Clytes, or as a ratio of copper windings, denoted as X*X. confusing to be sure. a 2807 is the same as a 9X7. A 2806 is the same as a 10X6, ect.

As for ampedbike, No. those aren't real 9C's. They claim it's something similar. I don't think anyone has had an oppertunity to run a head to head comparison yet.
Ebikekit.com is the only Authorized American dealer of 9C. Ebike.Ca is the Canadian dealer I would recomend also.

 

[amberwolf]

For what application would you select a front hub drive over a rear?
What application for fixed vs geared?

I think a much better way to ask your questions to get the answers you really need is first to decide what your application *is*, and then find out what is best for that.

Otherwise you are in for what would probably be a few months' to a few years' learning to find out all the details of all the applications, methods of doing things, stuff there is to do it with, etc. I've been learning it for about 3 years now, a bit more, because I have many applications and had not found ES back when I started. Also because I try to make do with whatever I have, and so I often find an application for a method or object I already have, rather than the correct way, of finding an object for an application I need it for.

If your goal is simply to learn all about ebikes and such, then your questions are good ones. If your goal is to get an ebike for your own application up and running, the questions are sort of the opposite direction you want to go.

If I bought a 36v kit from, say Amped Bikes, how far can you overclock them?

Motors can almost always be run at significantly higher voltage. Controllers (part of a kit) often cannot be run much higher than their listed voltage, unless you wish to physically modify them and in some cases reprogram them as well.

Last, would I be better going with a kit, or sourcing my own from various vendors?

Do you need service or warranty support? Or are you going to do all your own setup and repairs? THe former suggests a kit is better, but you may be able to get a better deal and also get exactly the items that suit your application best if you do it yourself.

 

[litespeed]

For me I wanted low end torque most of all because it's a bike and used at slower speeds. Stop and go on streets, trails or what have you. I'm 6'4" tall and 215 lbs so I'm not a light weight. I have some pretty steep hills and was realistic knowing that being a bike and riding on trails, paths, side walks and the like wasn't going to permit me to do extended high mph riding. I chose a geared BMC motor from Ilia ( http://ebikessf.com/catalog ) and couldn't be happier. I'm running the 600 watt speed version at 66.6 nominal and 75.6 volt hot off the charger (18s3p lipo's ) at 15 amps. My no peddle speed on flat pavement is 33.8mph. Would I like to go faster...absolutely but 90% of my riding is at the 20 to 30mph range. I also was able to squeak out a ride of almost 35 miles on 10.2 of the available 12 amps (80% capacity lipo rule!!!) with an average speed of 22 mph. For a last note the 33.8 mph with no peddling and all the rest is with me sitting upright on my XL bike. The controller and hub stay cool most rides but when I go off road (grass and light dirt trails with intermediate hills) the controller and hub get warm. Max has been 120 ish.

http://endless-sphere.com/forums/viewtopic.php?f=6&t=21516

For my next bike I do want a "motorcycle replacement and will either go with a big DD hub or R/C motored bike but I'll use it to ride with traffic......

Good luck with the decision.

Tom

 

[sharp21]

It seems like the way to go is to buy the best motor you can afford, followed by controller then batteries. That way the motor will be able to take the upgrades later, the controller is relatively cheap in comparison so that can be upgraded as needed & the batteries will need to be saved up for no matter what!

Do most hub drives have the option of attaching a disk brake to them? I know the eZee bike kit is set up for that

S.

 

[marose1]

I bought the BMC rear 600W torque motor/wheel from Ilia for my brother and he loves it. I am getting ready to purchase a hub motor for myself -- probably the same motor that I purchased for my brother, but I am curious as the what are currently considered to be the best quality geared and DD hub motors under 750 watts REGARDLESS OF PRICE.. BMC, eZee and Amped sell geared hub motors -- is one currently considered to be of superior quality/construction to the others? Also, Nine Continent, Crystalyte, Amped, BMC v4 (not out yet?) and others sell DD hubs -- is one currently considered to be of superior quality/construction to the others?

 

[biohazardman]

Quality wise from what I have read the BMC and E-zee geared hubs are comparable China quality motors. Looks like for the money the 9C can't be easily beat although if you want the most power and don't mind the extra weight the 53xx or similar C-lites are the ticket in the DD. As far as the disk brake capabilities you need to watch what you buy as some are some are not. I like my BMC 600W rear motor has lots of torque for the hills and a good 34mph on 52V and hole for the disk brake as well. The wires heat up on the longer steep hills but that's a common problem with most of the hub motors. I do tend treat my BMC geared motor a bit better than I did my DD unit plastic gears and all. Over 3K on it replaced a poorly fit cover plate bearing at 2k is about it. The newest version of the BMC 600 has the V3 clutch so you might want to be on the watch for that as it is posed to be the latest and greatest. Good to get a kit to make it more plug and play as well as matched components so things will play well together. Even my GM 500w DD has near 3K on it also with no motor problems. That’s not to say the regen controllers did all that well as they died repeatedly. So plenty of motors out there personal preference as to weight and power I guess.

 

[sharp21]

The Amped geared hubs are supposed to be very high quality. They are produced at their own factory in china, to their own specs.
S.

 

[dogman dan]

For 30 mph + The 5304 cyrstalyte or 9c 2807 or 2806 are your best options. Put 72v through either of those and you will be plenty fast.

What do you want to do with the bike? For a daily commute, a 48v pingbattery type setup works very very well. Charging is easy. The 2806 or an Aotema kit would give you 30 mph, with slightly less performance on extreme hills.

But if it's more of a recreational bike, then go to lipo for it's lower weight and ability to expand to 72-100v as you get the money. Do some learning curve stuff with 14s battery,(48v) and a cheap 48v controller. Then get a 72v controller and more battery later. Rear hub if you are going with that much power. I'm trying some racing with front hub, but anything over 2000 watts front hub starts to show the reason big motorcycles never put front drive on the bikes.

 

[sharp21]

What is the difference between a 48v ping type & a 14s, which is also 48v?
S.

 

[Jeremy Harris]

What is the difference between a 48v ping type & a 14s, which is also 48v?
S.

A 48V Ping battery is 16S of LiFePO4 cells which is actually 51.2V (16 x 3.2V) , 14S of LiPo cells would give you 51.8V nominal (14 x 3.7V).

Jeremy

 

[dogman dan]

The the 16s ping and the 14s lipo have very similar voltages. Both would make a 9 continent 2807 go 27 mph. The ping has a c rate of 2 while the lipo could have a c rate of 15- 50, or more. What's the difference? Not much if you are commuting and running a 20 amp controller. The typical 48v 15 ah pingbattery will provide 30 amps, and be plenty for the typical bike kit controller. But if you go to a 50 amp controller the ping's low c rate won't allow enough amps without damaging the cells. But go to 30c turnigy lipo, and you can easily draw 300 amps from a 10 ah pack! So the lipo can handle discharging the same watthours in a lot less time if you need to go from 0 to 40 mph in a hurry. The typical bike motor kit with a 48v ping is not all that slow though, so most commuters get by just fine with 48v and 20 amp controllers.

 

[sharp21]

So the 'S' designation refers to a single cell in the pack, with a small voltage, that is dependent on the battery type?
S.

 

[spinningmagnets]

In the names of LiPo battery packs, "S" means series, and "P" means parallel. I'm told each cell shouldn't be charged to over 4.0V, and they also should not be drained below 3.4V It seems 6S is becoming very common because you can get a single brick in that voltage, I think that most people who want 8S, 10S, and 12S have to parallel two lower voltage packs?

So, the voltage of a 6S pack would run between 24V off the charger and you shouldn't run it below 20.4V, but its discharge profile voltage is pretty flat during most of the ride, and you would probably read around 22.2V from a 6S pack (6 X 3.7V) I am still learning...pic is from the battery section of ES.

 

[dogman dan]

I lost my page of links when my laptop crashed, but dig down in the battery section and there is a lipo noob links thread with some links to good reading for those interested in lipo.

 

[sharp21]

Ohhhh... That makes perfect sense when I see it in print!

So a 14S battery pack will give me about 48V. What kind of range can you get from that? And how big is it?

The connection I am not making is why people are using SLA batteries when something small & powerful like this is available?

S.

Edit: Also, a lot of these packs look home made. Is that the case? Are the cells purchased individually from an RC shop then connected together? How dangerous is that?

 

[dogman dan]

Partly it's fear of exploding batteries. But those were 2-3c rate types. Now we have 30c lipo that barely even warms up when putting out incredible watts. You still don't want to charge one that has been overdischarged though. The modern chargers will check for that first before starting.

But mostly it's cost. The lead gets the bike on the sales floor cheaper.

The current lipo from hobby king is not really intended to run bikes, nor are the chargers. So there is a bit of homebuilding of wiring harnesses to put them together in series, and to paralell packs into larger ah units.

Typically people buy 5 ah packs for $40-60 each, and paralell at least two into a 10 ah pack. A 5 ah pack is jut too short range. Then making series connections, build the voltage the rider wants. Some will leave the pack assembled and charge with a power supply, monitoring it manually. Others break the pack back down to 5s or 6s sections to charge with a 6s lipo charger. then reconnect back to 14s or whatever to ride.

It's still somewhat expensive, but for about $400 you could have just about everything to make a 48v 10 ah pack and charge it. On a bike that goes 25 mph, that should get you 10-15 miles of range on typical street riding.

BTW, 7s lipo is dang close to 24v sla voltage. I run my 24v B&D mower on 8s and it goes like a bat out of hell. 8s is pretty close to 30 v when hot off the charger.

 

[sharp21]

What does the 'C' stand for?

Is connecting those batteries a plug & play affair, or is there sodering involved?

Is this kind of along the line of building a pack using dewalt batteries?

S.

 

[dogman dan]

the c rating is a measure of can the battery dispense it's full capacity at a given amp draw. It can be somewhat misleading, so the general advice is to go big and cut the advertized c rate in half for continuous use. When a battery is 10 ah in size, the calculations are easy. A 10 ah battery rated 1c could put out 10 amps continuous. But its lifespan is longer if used at 5 amps continuous. A 10 ah battery rated 2c should last well used at 10 amps. Better batteries like headways are said to take 5c, so even halfing the rate, you get 25 amps continous out of a 10 ah battery. At the top end of the scale are RC lipo, which often has a 30-50 c rate. At that point, even a 100 amp controller can't phase em.

So generally, the higher the c rate the better, and the higher the quality of the battery. Lots of the really cheap lifepo4 batteries on ebay are 1 or 2c. So the appeal of lipo is 30c or more, allowing racing and other high performance setups.

There are lots of ways to connect the lipo batteries. Some solder wires together, others crimp connectors to wire making wire looms to hook up all the batteries as desired.

http://endless-sphere.com/forums/viewtopic.php?f=14&t=21363&p=311264#p311264 here is how I did my last ones. I still break the whole pack down to individual batteries to charge.