First E-bike DIY project

[iballan]

Hi everyone.

Just moved outside the city and now my wife has to comute 24 km each day. 12 km in each direction, there are som medium hills on the route.

We have been looking at electric bikes, but they seem very expensive here in Denmark.

Instead i have decided converting her existing bike, to an electrical bike.

I have been investigation a bit, and i have ended up with something like:

- 500 watt front
- Battery placed in ack rack

I do not know what voltage i need, or which controller i need.

Here are som pictures of the bike i want to mount it on.




Could you please advise me what kit i need?

 

[Eskimo]

Put 500W DD hub on it with 48V battery and 20A controller, and at least one good torque arm.
Denmark is very flat, this set is bit sporty for that bike but not overkill. Gives you around 1000W tops, 40 km/h.
I am very happy with this same setup, it"s just nice amount of power. It is quite cheap kit too.
That fork looks like a steel fork, is it?

 

[iballan]

Thanks for your answer. I've been searching for som components, and this is what i have found so far:

500w 48v thumb Controller 160 USD
http://www.elifebike.com/peng/iview.asp?KeyID=dtpic-2013-9T-FNM6.74VME

Or
QQ http://www.elifebike.com/peng/iview.asp?KeyID=dtpic-2011-43-GS2R.234MU

Which one to choose?

Controller Case 3 USD
http://www.elifebike.com/peng/iview.asp?KeyID=dtpic-2013-7W-BAXN.27YMM

EBike Carrier / Back Rack 20 USD
http://www.elifebike.com/peng/iview.asp?KeyID=dtpic-2011-1A-H3XX.52NUT

Battery 335 USD
http://www.elifebike.com/peng/iview.asp?KeyID=dtpic-2011-1J-9479.18EUD

Cherger 35 USD
http://www.elifebike.com/peng/iview.asp?KeyID=dtpic-2013-7S-C50E.6BJRD

Torque arm 18 USD

Total USD 833 + freight

When shipped to Denmark, i will have to pay another 25 % in vat and 15 % in custom

Total USD 1.166,- + freight

Can you recomend som European suppliers, or will they still be more expensive than the total including freight?

I have som other questions:
Where do i mount the controller?

How long will the battery last fully charged? I know that batteries looses capacity over time. Is there any rule of thumb of how long time it will be usefull. (usage 5 days a week, 24 km in total pr day)

Do i need other cables?

Do you have any idea for ligths? Bakclight could be integrated on the batterycase/carier....

 

[iballan]

And yes, it is a steelframe and fork.

 

[Eskimo]

This is my set:

http://www.greencycle.fi/product/111/500w-36v-muunnossarja-antiwater---etupyoraan

It has worked two years very well. It takes 48V very nicely. It"s from Finland. Starting price is higher, but because of EU you don"t have to worry about customs etc. Freight from Finland to Denmark is propably not high, it"s road freight.
I don"t really know much about other European suppliers.
Controller can be installed just about anywhere, where cables permit. Try to find a place away from waterspray.
It depends about battery chemistry, what type of battery, how it ages. Other guys here could advice you better about other than LiPoCo batteries what i use.
As a rule of thumb i would say two years with full capacity. Don"t store it fully charged if it has lithium chemistry. Charge always just before you go.
DD-motor is a good choice for you because you don"t have hills over there, what i know about Denmark. DD-motor is great on straight flat tarmac ride.
Grin Technology in Canada offers the best torque arms, as far as quality. I use V.2 arms, which are easy to install and rugged. They bolt on fender eyelets.
If you are happy with 32 km/h, then 36V battery is enough for you. If you want 40 km/h, then you need 48V. It"s up to you.

 

[iballan]

Thanks for the help. I've been reading and reading and reading on this topic. I actually wanted to bud mid og rear drive motors, but since the bike have pedal back brake, it dos not seem like an option.

Finally I ordered something.

I ended up ordering at BMSBattery.

- EBike Torque Arm
- Bafang BPM2 48V500W Front Driving Bike Conversion Kit - RPM : 201
- 48V10Ah LiFePO4 Alloy 03-CASE EBike Battery With a Carrier Rack - AC Voltage : 200V~264V, Rack Color : Black
- LED810

I've ordered it with thumb controller. The bundle controller is KU123.
I will try the PAS function, but i have read a lot of people not liking the PAS.

I have been renovating the rear wheel (two broken spokes), changes the chain and the pedals.
Now I will just sit and wait (un)patiently until my package arrives

 

[iballan]

Can anyone tell me what the difference between theese two 48V 10 ah batteries are? (besides that the 03-case has a room for controller - to small for my controller).

http://www.bmsbattery.com/48v/468-24v-lithium-ion-little-frog-abs-shell-ebike-battery-pack.html

http://www.bmsbattery.com/48v/623-48v-15ah-lithium-ion-alloy-shell-ebike-battery-pack.html

 

[motomech]

I never saw this thread. You could have gone with a 328 wind @ 36V with a light weight rider. Oh well, it should really climb.

Here's some expert advice from D8veh:

<<<<I've bought several BPM kits, so I can explain a few things.

..... The normal 500w rear BPM kit comes with the KU123 controller that gives 30 amps, so at 36v, you use about 1200w, and at 48v, 1600W.
The motor has a lot of torque. The 201 rpm one will go a bit more than 25km/h, but not much. The 328 rpm one does about 40km/h, at the expense of a bit of climbing efficiency. They don't change the gear ratios. Instead, the motor coils are wound differently. There's not a massive difference in torque between the two, but the higher speed one uses more battery and gets hotter when climbing steep hills. I have very steep hills where I live, and the 328 rpm one has no trouble getting me up them.

Don't take too much notice of the photos on the BMSB site. Like most Chinese sites, they get things mixed up. The front BPM has the wire exiting next to the axle. I'm not too sure about the BPM2.

Don't go for a front motor unless you have strong steel forks. Even then, you'll get a lot of wheel-spin. A rear one is better for 500W.

The 30 amp controller is about as high as you'll want. Most people are happy with 25 amps at 48v.

...... but as a general rule, you need a high discharge rate one for 30 amps, so read the descriptions. You need one that can give at least 20 amps continuous.>>>>>

That is a lot of motor\power for the frt. of that bike.
She will have to be very careful.

 

[iballan]

Hmm now you got me confused!!!

What is 328 Wind?

I thougt i had read, that 500 W BPM kit with 48V would go around 40 km/h (with 201 RPM) is that wrong?

The front fork is steel.

I cannot use rear motor, because the bike uses pedal back brakes.

I will deffinately not like to make a too agressive setup. My wife has tried a Gazelle Ebike (Dutch brand) 250W motor and it was actually not helping at all uphill. I do not know the battery specs of that bike.

There are a few 3 % clims on her route (apprx 500 meters long each)

 

[motomech]

Hmm now you got me confused!!!

What is 328 Wind?

I thougt i had read, that 500 W BPM kit with 48V would go around 40 km/h (with 201 RPM) is that wrong?

The front fork is steel.

I cannot use rear motor, because the bike uses pedal back brakes.

I will deffinately not like to make a too agressive setup. My wife has tried a Gazelle Ebike (Dutch brand) 250W motor and it was actually not helping at all uphill. I do not know the battery specs of that bike.

There are a few 3 % clims on her route (apprx 500 meters long each)

A 328 wind is a faster spinning motor at a given Voltage. Off the top of my head, the slow wind 201 will do about 30 Kph on 48 Volts and will have very strong acceleration.
The 328 will do about 40 Kph on 36 Volts and 50 plus on 48V.
Although your hills are a bit long, the grade is not that steep.
I think the 350W BPM2, 328 wind @ 36 Volts would be a better fit for the bike and rider.
You can go to the simulator at EbikeCA and plug in the relavent motors and batteries and see the results.

 

[iballan]

Ok, now i am looking at 36V batteries. This is a jungle to me.

What maximum Continuous Discharge effect would i like to aim at?

Another question:

Why does BMSbattery recoment 201 RPM?

Quote from their website:

P.S. : High speed means low torque. Low speed means high torque. RPM means "Revolutions Per Minute". 201RPM is often used for 24", 26", 700C and 28" rim. 328RPM is often used for 16", 20" and 24" rim.

 

[motomech]

In general, it is a risky business to go inside the minds of the Chinese, but I think their recommended speeds reflect the Euro. legal speed of 25 Kph.
I am afraid you received some questionable advice early in your thread. You should have kept it active longer to get more input.
The larger geared motors, like the BMP are too much for that bike and a rider of the fairer sex. It will adversely effect the handling and will require accurate throttle control when the road surface is damp.
I would have recommended a smaller "mini" geared motor, which would have enough power and speed.
From BMS Battery, the most tested and easiest to install would be the Q100H:

http://www.bmsbattery.com/ebike-kits/632-250w350w-q-85100sx-motor-e-bike-kit.html

It is much smaller than the picture. You can see the size in my Rocky Mountain build thread below.
You will note that it comes in a 260 wind speed, which would do 31 to 33 Kph @b 36V.
48 V would be better, but unfortunately, BMS Battery does not offer a controller that works at 48V(some of us are working on this problem).
If she is a strong pedaler, a 328 Q100 might work at 36 V. It would do 36 to 37 Kph, but would not be a very strong climbing motor.
If I were you, I would order the Q100H frt. kit listed above and a bare motor Q100 328 to try out later. It is easy to change motors, the core is swapped out.


http://www.bmsbattery.com/front-driving/298-250w350w-q-85100sx-motor-e-bike-kit.html

When ordering the Q100H kit, you want to use the SO6S controller and order the LCD3 display and speed sensor.

For a battery, a 15 Ah will give her the range plus some extra. I would try and use this one:

http://www.bmsbattery.com/36v/475-36v-15ah-lithium-ion-electric-bicycle-battery-pack.html

I would require fabricating some sort of mount, but would leave the rear rack for cargo. A rack battery of the same capacity would be an option.

Some extras you might think about getting would be:

A pair of torque arms
A left-hand half-twist throttle
and a KU63 or Ku65 controller as a spare.

 

[d8veh]

Assuming that the forks are 100mm wide. I think the 350W BPM kit would be perfect at 36v with any 36v 15aH battery. The 201rpm one will do about 30 km/h depending on which code number they supply. The 500w one spins the wheel too easily.

 

[motomech]

that is good news, D8veh has lot's of experience with the BPM. I forgot about the 350 Watt version. I assume that he would recommend the BMSB 9-FET, 22 Amp controller.

 

[iballan]

Ok, i have now been reading about the Q100H motor. 260 rpm would be a good compromise between speed and torque, as i understand

Would you prefer the BPM over the Q100H?

BMSBattery recomends following controllers for Bafang: You can select S09P, S12P or S12S controller for this motor.

This will still be a 36V kit right?

What rpm should the bafang have ? 201 or 328?

 

[iballan]

Bump

 

[motomech]

Yeah, I really prefer mini-motors, when they fit the application.
They really retain that bicycle "feel". A bare Cute motor weighs 1.8 Kg. while a BMP is around 5 Kg.
Did you see this thread?
http://endless-sphere.com/forums/viewtopic.php?f=2&t=59345
He runs a regular Q100 on 50 to 60Volts with a KU65 controller.
I ran KU63 controllers (basicly the same as the KU65) for a long time on 50 to 55 Volts with no problems
You could run a Q100H on a 48 V battery while using the KU 63 or KU65 controller.
The simulator shows a top speed of 38.5 Kph and the ability to climb a 3% grade for 19 Kph before overheating(with no pedal input).
Using the KU controllers would mean the loss of the display unit, but you could add a cycle computer and a Voltmeter, easy to do both.

 

[iballan]

Ok. now im back again. I had to wait for BMSBattery to confirm refunding the old Bafang500W order. Now my money has been refunded.

I think the 48 V Q100H solutions sounds good.

I am planning to make the following setup:

Q100H 260 rpm http://www.bmsbattery.com/ebike-kits/632-250w350w-q-85100sx-motor-e-bike-kit.html
Torque arm http://www.bmsbattery.com/36v/450-a-pair-of-ebike-torque-arm.html
KU65 controller incl. led http://www.bmsbattery.com/controller/415-hall-sensorsensorless-250watts-brushless-hub-motor-controller.html
Controller case http://www.bmsbattery.com/controller/365-ku63-controller-case.html
Thumb throttle http://www.bmsbattery.com/accessory/612-thumb-level-throttle.html
Brake Grip http://www.bmsbattery.com/ebike-parts/52-brake-grip.html
Pedalsensor http://www.bmsbattery.com/ebike-parts/49-pas-pulse-padel-assistant-sensor.html
Batteri rack http://www.bmsbattery.com/accessory/485-rack-for-our-03-and-05-battery-case-.html
48V 15ah http://www.bmsbattery.com/48v/403-48v-10ah-lithium-ion-alloy-shell-ebike-battery-pack.html

Total 524 USD

I'm planning to order two of each part, besides the battery. Then i will have the posibility to play with another bike, and also have spares if needed.

 

[iballan]

Finaly i received the email from BMSbattery.

Your order has been shipped.

I decided to build my own wheel, and i have already received rim, spokes and nipples from another company. (Rosebikes)

Looking forward to get my package, and hoping TNT is fast

 

[iballan]

WOW, this is awesome.

Recieved the kit las week. My friend build the wheel yesterday, and today i did the first real test of the bike.

Pedal assist is working great, i am really impressed right now. I was smiling all the way to work Maybee i should build one for myself

Installation was easy and motor is not noisy at all. The 350W combined with 48V seems to be a really good combination.

I will come back with pictures later.

 

[Lebowski]

your title says it all, First DIY project... to be followed by second third fourth and fifth

 

[bikeonfire]

Following...

 

[d8veh]

WOW, this is awesome.

Recieved the kit las week. My friend build the wheel yesterday, and today i did the first real test of the bike.

Pedal assist is working great, i am really impressed right now. I was smiling all the way to work Maybee i should build one for myself

Installation was easy and motor is not noisy at all. The 350W combined with 48V seems to be a really good combination.

I will come back with pictures later.

Can you confirm what you finally got? Your shopping list shows a KU65, which will probably fail with a 48v battery sometime in the future.

If you want to buy another kit, they have some new batteries with included 20 amp sine-wave controllers in them. A 36v one with the 260rpm Q100H should be pretty good.

 

[iballan]

I got the KU65 controller. I thought this was the recomendation when running 48V with the q100.

Why do you think the KU65 will fail in the future?