Advice on my first build: DD rear hub 48V 1000W

nezhac

100 µW
Joined
Nov 3, 2017
Messages
8
Hi everyone,
I've been trailing through endless sphere and r/ebikes for a while now and have gotten the courage together to go to the ordering part. I've got previous experience riding and maintaining motorbikes as well as bicycles, but nothing electric. Changing tires and wheel bearings, balancing/truing spoke wheels is something I'm comfortable with, just nothing electric.

I want an ebike for commuting, it's about a 20km/12mi round trip. Maximum grade on my commute is 5%, although for other general usage it can be 7% with short sections (2-300 meters) of 9%. All of this is going to be on smooth asphalt roads. The law here limits max speed to 25kmh/15mph and 500W if you don't want to pay insurance (which I don't). I don't have a bicycle yet, but I've got my eye on a cheap used Merida Kalahari 550: http://www.velospec.com:8080/en/bikes/merida/kalahari550sx-2006. Total budget would be around 1000-1500$, I'm obviously happy to save money but if the extra bucks are worth it then I'll put them in.

I want something simple and robust to get the job done. From what I've read, a hub DD will last the longest. I read good things about leaf motors, the 48V 1000W is recommended and seems like a good bang for the buck. So either I'd go for this leaf motor :http://leafbike.com/products/diy-bi...-rear-hub-motor-bike-conversion-kit-1067.html and get a battery from em3ev. Or go with a recommended eBay supplier, for example getting a full kit with battery: http://www.ebay.co.uk/itm/1000W-Ele...hash=item1a2887e396:m:myFSE2UyBrbMot26KATYSKg

I thought I'd limit it to 500W and 25kmh/15mph to comply with the no-insurance terms, with the possibility of increasing it in the future. From what I've gathered, this is what I need to look out for:

- 135mm rear dropouts is standard for rear hub kits, make sure this matches between the bicycle and motor
- Get torque arms if getting a bicycle with an aluminum frame
- 26" rim is also standard, order correct size matching bicycle
- Max discharge rate of battery matching controller
- Make sure battery can fit in the frame, best point for weight distribution would be on lower downtube

Anything else crucial that I'm missing out?

How about the leaf motor + em3ev vs the ebay supplier? It seems the ebay supplier is cheaper and supplies a 48V 15Ah battery with the kit. I expect delivery to be shorter as it's UK vs China. However, there's no info about the brand of motor, or if it's really a direct drive. It may also be simpler because everything is sold as a kit, so it all fits together easily. I'd like to get a 48V battery in any case to be able to test out the entire 1000W. I may also switch out the bicycle for something nicer if I'm not happy with it.

Thanks for taking the time to read and writing down your thoughts!
Nez
 
I am pretty much in the exact same boat as you. Sounds like we are thinking about building very similar bikes. My plan is to go with the leaf 1500w motor, but that's because I want a little extra power for fun. User neptronix has a thread where he tests the leaf 1500w motor extensively which is what turned me on to it (as well as several other reports I've read). I'm sure the 1000w motor is good as well if you don't need or want the extra power.

But anyways I have a thread going which I'll link below. If you scroll down, I have a list of parts I'm planning to buy (I still could change my mind though). If you want to check it out, it might be helpful for you when picking parts for your bike.

https://endless-sphere.com/forums/viewtopic.php?f=3&t=90947
 
If you are going to limit to 15 mph, 500w, then you should not carry around a 15 pound DD motor wheel. (1000w kit, but the motor is still a 500w rated motor in most cases)

Look at lighter 500w rated geared motors for your commute. 36v will get you about 700w total, closer to legal. Choose a low speed wind, so your 36v top speed is also closer to legal. Nobody cares about your wattage, they will notice, if at all, when you haul ass.

If you want legal, then look at 350w, 36v, geared motor kits. They will still climb your hill, with brisk but not exhausting pedaling. Your battery can be much smaller and affordable, and your bike will be 20 pounds lighter. Big motor needs a big expensive battery.

On the other hand, you could just ride the 30 mph, 1000w setup at 15 mph, as long as cops are not going to bother you much where you are. I do this myself. I have a 30 mph limit here, and my bike does at least 35 mph, 40 on a downhill. 2000w. But mostly I ride 15-18 mph, pulling about 300w, because I like to go slow enough to enjoy the view, and pedal along with the motor. No cop here cares about my bike, because I'm so rarely seen going 35 mph. I use that burst of speed only when needed, on a dangerous road I really should not bike on at all. 95% of the time, there is a safe route to avoid a speedway road. When not, I unleash the monster.

So why do I ride the monster motor? Because at times I tow a trailer, which can be up to a 150 pounds more weight on the bike, and I live in the mountains. With the trailer up Augustine pass, I need all 2000w to go 15 mph up the mountain.
 
Welcome to the forum.

Sounds like you have a good grasp on what you need. The motors you picked are overkill for your needs, but overkill can be fun. EM3EV would be the place to get the battery, but Ebay could be fine for the motor, if you accept the risk and understand the drawbacks. The largest difference between an ebay vendor and a known quality vendor is the quality of the rim and spokes used. The motors themselves are often the same, but what ends up on ebay can be a few revisions behind what a name brand vendor is offering.

Torque arms are like condoms, Use them every time you ride. A properly tightened axle nut on a steel frame should be enough to hold the torque, but things happen, nuts loosen, and a 1000 watt motor has enough torque to destroy the dropouts and free it's self from the bike if it's not locked down.
 
Where are you located?

If I were you, I'd just go ahead and buy the Leaf 1500W kit with the KT display. Then for a battery, I'd just go to Home Depot store and buy some tool pack batteries.

EGO 56-Volt 5.0 Ah Battery
Model# BA2800
(194)
$219.99

Or look around for deals

Ryobi 18-Volt ONE+ Lithium-Ion High Capacity Lithium+ Battery Pack 4.0Ah (2-Pack)
Model# P122
(1964)
$99.00
*nets you 36V 4Ah, if you want 36V

Ryobi 40-Volt Lithium-Ion 5 Ah High Capacity Battery
Model# OP4050A
(351)
$139.00

DEWALT 20-Volt MAX XR Lithium-Ion Premium Battery Pack 6.0Ah (2-Pack)
Model# DCB206-2
(25)
Was $189.00
$159.00
 
markz said:
Where are you located?

If I were you, I'd just go ahead and buy the Leaf 1500W kit with the KT display. Then for a battery, I'd just go to Home Depot store and buy some tool pack batteries.

Ryobi 40-Volt Lithium-Ion 5 Ah High Capacity Battery
Model# OP4050A
(351)
$139.00

FYI. That Ryobi is not good for ebikes. I have one. Works OK for my 250W motor with 10A controller, but only delivers about 100 WH or 3AH. Resets if used on a 25A controller, so it cannot run a big DD motor. You also have to make a connector for it.
 
docw009 said:
FYI. That Ryobi is not good for ebikes. I have one. Works OK for my 250W motor with 10A controller, but only delivers about 100 WH or 3AH. Resets if used on a 25A controller, so it cannot run a big DD motor. You also have to make a connector for it.

And even at the rated 250 watt/hour, that's a fairly expensive battery for the energy it can store. If it delivers less than the rating, then it is super expensive.
 
Just what Dogman says.

You will be much happier with a bike that is 20 pounds lighter .
Also
You can get that 350 watt 36 volt motor and run it at 48 or 52 volts, But, It is better to just get a 500 watt motor and just ride it around at your 15 mph speed limit most of the time.

I can vouch for the Mac motor from Em3ev.com , It is a good motor.

Others will say they have good results with a Q 128 from BMS Battery,

and
Others are happy with the BBS02 From Luna, or a complete bike from Luna.
and


Many are happy with the Motors/Controllers/the Advanced Battery Charger , and the Cycle Analyst from ... Grin Technologies in Vancouver , B.C.

Just go for lighter weight conversion for now, no need for a DD Hub for the speeds you will be going.



dogman dan said:
If you are going to limit to 15 mph, 500w, then you should not carry around a 15 pound DD motor wheel. (1000w kit, but the motor is still a 500w rated motor in most cases)

Look at lighter 500w rated geared motors for your commute. 36v will get you about 700w total, closer to legal. Choose a low speed wind, so your 36v top speed is also closer to legal. Nobody cares about your wattage, they will notice, if at all, when you haul ass.

If you want legal, then look at 350w, 36v, geared motor kits. They will still climb your hill, with brisk but not exhausting pedaling. Your battery can be much smaller and affordable, and your bike will be 20 pounds lighter. Big motor needs a big expensive battery.
 
docw009 said:
FYI. That Ryobi is not good for ebikes. I have one. Works OK for my 250W motor with 10A controller, but only delivers about 100 WH or 3AH. Resets if used on a 25A controller, so it cannot run a big DD motor. You also have to make a connector for it.

I'd actually look into the Dewalt, b/c of the higher Ah.

DEWALT 20-Volt MAX XR Lithium-Ion Premium Battery Pack 6.0Ah (2-Pack)
Model# DCB206-2
(25)
Was $189.00
$159.00
 
$ 159 x 2 = $ 318 Plus tax, plus shipping, so over $ 350 , and it will only have 6 amp hours.

Too much $ ,

better to just get a battery from the known and trusted vendors. Grin Technologies / Luna / Em3ev
 
I just bought 5 x 36V 4.4 Ah batteries from eBay for ~ $160. I would recommend that if you live in the US. I wired them in parallel with xt60 connectors for 36V 22Ah 792Wh battery for like $165 including the connectors. I already have a 36V ebike charger so I am using that.

It is also nice having the 10s2p packs in a modular format so I don't need to take all 5. Each one is supposed to put out 20amps or something but I am only using 10 amps total so 1 pack is able to power the bike by itself if necessary.

One downside of the packs is that I don't think the BMS balances the cells. It does protect the cells from overcharging and over discharging though.
 
SHIBBY said:
I just bought 5 x 36V 4.4 Ah batteries from eBay for ~ $160. I would recommend that if you live in the US. I wired them in parallel with xt60 connectors for 36V 22Ah 792Wh battery for like $165 including the connectors. I already have a 36V ebike charger so I am using that.
<snip>
One downside of the packs is that I don't think the BMS balances the cells. It does protect the cells from overcharging and over discharging though.

The other negative is weight. There are more energy dense options. But still, a very good value if they suit your situation. I've been running seven in parallel for my regular commute of 32 miles roundtrip.

I only charge mine to 41v(in the interest of longevity) with an occasional full charge right before a ride.
 
ScooterMan101 said:
$ 159 x 2 = $ 318 Plus tax, plus shipping, so over $ 350 , and it will only have 6 amp hours.

Too much $ ,

better to just get a battery from the known and trusted vendors. Grin Technologies / Luna / Em3ev

Actually its 36V 12Ah for $318, shipping to your closest HD store is free, and yes whatever the taxes are. Still works out to ~$25 per Ah compared to $60 per Ah for legit batteries from em3ev and the like. Even cheaper is to tab weld or solder some cans together from ru.nkon.nl, then it works out to $12 per Ah, if you already have a suitable soldering iron and solder. Can buy one cheaply if you dont. You could also look around Endless Sphere and see the other concepts people have done to connect cans together. If I were to solder cans together to make 36V or 10 in series, I'd make 18V modules, connect two to make 36V, connect three to make 54V.
 
markz said:
ScooterMan101 said:
$ 159 x 2 = $ 318 Plus tax, plus shipping, so over $ 350 , and it will only have 6 amp hours.

Too much $ ,

better to just get a battery from the known and trusted vendors. Grin Technologies / Luna / Em3ev

Actually its 36V 12Ah for $318, shipping to your closest HD store is free, and yes whatever the taxes are. Still works out to ~$25 per Ah compared to $60 per Ah for legit batteries from em3ev and the like. Even cheaper is to tab weld or solder some cans together from ru.nkon.nl, then it works out to $12 per Ah, if you already have a suitable soldering iron and solder. Can buy one cheaply if you dont. You could also look around Endless Sphere and see the other concepts people have done to connect cans together. If I were to solder cans together to make 36V or 10 in series, I'd make 18V modules, connect two to make 36V, connect three to make 54V.

Yes, this isn't as bad as some of the others power tool batteries that you listed. But using the Grin 36v 14ah battery as an example, it comes in at $30 per 36v Ah - only a little bit more. And it comes with a charger, and it is already configured to mount to an e-bike downtube. You don't have to fiddle with building a case etc.

But if you like to fiddle like I do and are willing to take a bit of a chance, you can get down to $6.25 per 36v Ah (and I'm counting each pack as 4 Ah, not 4.4 Ah) with batteries on ebay if you purchase packs 36v LG batteries in lots of 10.
 
Ok, I now see that it is a 2 pack for that $ 159. I was thinking it was for one, since that is the usual price for 1 pack when I have looked at HD battery packs in the Past.

So for 4 of them it would be $ 346-$ 347 here in California , after tax.
I would like to see someone take them apart then wire them together , then post the amount of time to do that to see if it is worth it .
Also what make and model of cell's are they, for low amp draw they might be just OK, but I would question amp draw's of over 15 amps .
I have a 15 amp controller on a very small and low power Q100c motor. But the original poster says he wants a larger/more powerful motor.


markz said:
ScooterMan101 said:
$ 159 x 2 = $ 318 Plus tax, plus shipping, so over $ 350 , and it will only have 6 amp hours.
Too much $ ,
better to just get a battery from the known and trusted vendors. Grin Technologies / Luna / Em3ev

Actually its 36V 12Ah for $318, shipping to your closest HD store is free, and yes whatever the taxes are.
 
If you go with a 1000w dd motor kit, you'll need about a 4 pack of those dewalts in paralell to run it. At least 10 ah, preferably 20 ah.

Part of why a petite motor might suit your 15 mph needs better.

I'm not saying overkill is wrong, it IS fun, when the cops are not looking. Or could care less like they do here.
 
Thanks for all the feedback!

Based on what you've said I'll probably re-adjust to a 500W DD. I'm sure it'll still do faster than 15mph on flat roads if I want to.
But if I'm going for that smaller motor it seems LunaCycle becomes more interesting, with the smart pie v5.

I'd go for a standard 48V 13.5Ah battery, should be plenty for my 12mi round-trip. From what I've read it also seems the smart pie can do 1000W peak, which could be fun for mini boosts. Apparently the pedaling resistance with the motor off is also less than the bigger magic pie, which could be nice if I happen to run out of juice. What I really want is to stay with DD for reliability reasons, which the smart pie is.

I'm in central Europe, so ordering from Luna is a little expensive. But if I get a friend or two along we can split the shipping.

So thoughts on the build? I'm ready to press the button :D
 
[strike]You do realize that a smart pie is NOT a DD (direct drive) but rather a geared hub[/strike] with a built in controller? Granted that it is as heavy as DD hub. You will also need a Windoze computer to program it. If you are in Europe then you might want to consider ordering direct from Golden Motor in China. Be sure to get a battery pack with a switch because the GM system does not have one. FYI I am running a Smart Pie with a Luna 52 volt pack and hit right around 900 watt peaks (see Grocery Getter in signature).

"I just got back from my usual trip to the Post Office and Kroger grocery store. That is a round trip of 6.2 miles (per google maps). I used 3.6 Amp Hours of energy (I do not pedal much). That works out to 1.7 miles per amp hour. If I derate the battery to 12 Amp Hours then I should have a realistic range of about 20 miles."

Reference: https://www.goldenmotor.com/
 
Thanks for the info LewTwo!

It's not a DD? I looked around a bit more and I couldn't get any info on whether it's a DD or not, anyone care to chip in?
Here's a link from the CA web saying the SP5 is gearless https://www.goldenmotor.ca/products/Smart-Pie-5-(VECTOR)-16-Inch-Front-Conversion-Kit.html
And two more, one from GM forum and the other electribke.com
https://www.goldenmotor.com/SMF/index.php?topic=4631.0
https://electricbike.com/forum/forum/kits/golden-motor-magic-pie/7799-smart-pie-v5-vs-mp-edge
I'm a little confused as to whether it's geared or not now...

Do you have any other recommendations for a small and reliable 500W DD?
Thanks!
 
Get a good or great battery don't get some kind of Flea bay s*** that ain't going to work that you can't return cuz batteries can't be returned to China it's a one way ticket. Em3ev is worth the money plug and play. His motor kits are more but better rims and spokes.
 
nezhac said:
Thanks for the info LewTwo!

It's not a DD? I looked around a bit more and I couldn't get any info on whether it's a DD or not, anyone care to chip in?
Here's a link from the CA web saying the SP5 is gearless https://www.goldenmotor.ca/products/Smart-Pie-5-(VECTOR)-16-Inch-Front-Conversion-Kit.html
And two more, one from GM forum and the other electribke.com
https://www.goldenmotor.com/SMF/index.php?topic=4631.0
https://electricbike.com/forum/forum/kits/golden-motor-magic-pie/7799-smart-pie-v5-vs-mp-edge
I'm a little confused as to whether it's geared or not now...

Well to be honest, I would have to tear down the Smart Pie before I could swear it was a geared hub (and I am NOT inclined to do that without a darn good reason). There are however major differences between the Smart Pie and the Magic Pie series. I have always thought that those difference were consistent with the difference between a DD and geared hub. When I was first looking at the GoldenMotor line I tried to find something, make that anything, that definitively described the differenced in the two series. I found nada but I distinctly remember 'someone' pointing out that the Smart pie is a geared hub.

The one person that could definitive answer this question (and natively speaks english) is Gary Salo of Goldenmotor Canada. I am going to try email him after I post this message. He has on occasion posted on this forum.

nezhac said:
Do you have any other recommendations for a small and reliable 500W DD?
Thanks!
I do not ride DD hubs ... I happen to prefer the lighter, smaller geared hubs that suit my purposes. I do note however that GoldenMotor does have a 500 watt DD hub that is known as the the Magic Pie Edge. This is newer, smaller, lighter design than the traditional Magic Pie. I believe ALL GoldenMotor "pie" designs include an internal controler and I believe that they use the SAME controller and software (for a given generation).
 
I stand corrected:
Gary Salo, 5:58 AM (0 minutes ago)

Direct drive

Enjoy the Ride!
Gary
So I have at this point what the definitive differences are between the Smart Pie and Magic Pie series.
 
Well, I was going to order the smart pie form Luna today and I got an answer form their sales team (super fast answer btw):
"The smart pie is throttle only."

In order to comply with the law I need a PAS motor, and ideally i want it to be a DD too, for reliability. I then found this in relation to golden motor:
https://www.goldenmotor.ca/FAQ/questions.php?questionid=167
From what I've understood any of the Golden Motor v4 or v5 can be pedal assist (PAS), but you need a Cycle analyst V3 and a pedelec ring (for cadence assit). A cycle analyst v3 with a torque sensor is apparently even nicer but more expensive. So why don't Luna cycle sell the CAV3, pedelec ring or torque sensors?

So the question is what do you think is my best choice for an easy installation? Get a smart pie, add the CAV3 + ring to get PAS? Or go with a leaf rear 500W DD kit which already ships with PAS? The smart pie does have the + of an integrated controler, but only if everything works with the CAV3 and PAS.

Thanks!
 
It's easier if you just get a kit that does what you want. The Cycle Analyst is a fantastic tool and enhancement to almost any e-bike, but just setting it up amounts to learning a new set of skills.

If you can install Debian Linux, or root your phone without somebody talking you through it, you'll probably enjoy setting up the Cycle Analyst. If that sounds painful to you, maybe find a kit that doesn't require setup on the programming side.
 
If I were you, I'd buy the Leaf 1500W DD kit with KT display from www.leafbike.com and get the motor already laced, and you will be rocking in style.
 
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