Advice needed for my new project

[zooz]

Hi All,

I appreciate your time reading and responding to this thread.

So, I have had a 350W BPM motor with 450W controller for some time now on my Mongoose Rockadile ALX mountain bike, it's been running okay considering my weight (I am pretty tall and big). It pushes me around London without many issues.

The company I work for is moving office, which will increase my travel costs by travelling on a public transport, so the company agreed to pay the difference for the whole year - which is kinda cool.

So I thought I might as well use that amount of money to build a new e-bike project for work commute as well as for leisure. I've been reading ES for some time now, it's a great place, especially the people who are lurking in there

I have got a budget of about £1000 (approx $1500 USD). I have a Mongoose Rockadile ALX 2010 bike with hydraulic disc brakes, so I will not need to buy a new bike. I can dedicate roughly £1k for the motor, battery, controller and other bits and pieces. I do not want to go mad and waste too much money obviously and I like the DIY idea.

I would like to get about 1kW read wheel drive setup with 48V 10Ah LiFePO4 battery. I was thinking about Crystalyte HS3540 rear hub motor with Crystalyte controller and self-built headway battery. But I have so many questions about that, so I will try to list them below and if you could just let me know what you think - shout if I am talking total nonsense.

1. What would be a reasonable rear DD motor for about 1kW of power? Does Crystalyte HS3540 make sense?

2. What controller should I get? AFAIK Crystalyte do some nice configurable controllers? Will I need to buy the expensive add-on for their controllers so I can re-configure them?

3. Does it make sense to build my own battery out of Headway cells?
I was thinking about 16S Headway 38120S 10Ah 10C to get 48V and a pretty good amps out of it. I think that I can handle the battery without a BMS. The main reason why I want to build my own battery is that I can then design my own battery mount and probably fit a battery inside the triangle of my bike. I hate having 6kg on a back of the bike. It's wobbly and sometimes the bike gets unstable.

4. What charger?
Knowing the fact that I will need to balance every cell separately, I will need a smart charger for lifepo4. Is there a charger which can charge 16S cells at the same time as well as balance them using balancing wires?

5. Speedict or Cycle Analyst? I looked at the Speedict features it seems very cool. Being an IT guy and especially involved in open source a lot, I liked the idea of being able to control my e-bike using my android phone or even a computer.


My current kit was bought from BMSbattery, they seems to be okay, but it takes ages for them to ship an order. However they do not sell Crystalyte motors anyway.

What suppliers would you recommend to buy Crystalyte stuff from? I live in the UK, so I would prefer the ones in the UK (if there are any).

I guess there is too much from me to absorb in one go already, so let's take it from there then. I am sure I will have a lot more questions.

Thanks in advance for your answers and ideas!

-- zooz

 

[Eujangles]

Hi Zooz, welcome to the forum.

I'm no expert but I'll do my best to help answer your questions:

1. The crystalytes are pretty well regarded motors that would definitely do the trick for you. If the HS series is the one I'm thinking of, they're pretty heavy duty and meant for big time overvolting. You might be better off with a 9c motor, both for your power range and your budget.

2. Not too sure about this one...though I would recommend getting a controller with your motor from the same place. What is your goal in configuring it yourself? It may be possible to get whoever you are ordering it from to do a custom configuration.

3. Headways are good cells, with fairly high discharge rates, and are apparently pretty easy to put together into packs. It all depends on how much work you want to put in to your project, and how much you'll wind up saving by doing it yourself. I think ampedbikes.com has headway packs pre-assembled. If weight is a concern lipo is the way to go, but do some research before you hop in to that (they can kind of, well...explode).

4. Again not sure here, but I can tell you a BMS would probably sort out your balancing issues. If you decide to just buy an assembled pack, all this stuff would be included. Since you're looking for 48v 10ah lifepo4, I'd recommend just checking out what's on ebay...battery pack prices seem to have dropped a bit in the last year or so.

5. most people here seem to go for the CA as something tried and true, but the speedict sounds pretty awesome too.

Not sure about in the UK, but I buy my stuff locally at ebikes.ca, and they ship.

 

[cal3thousand]

I don't have any direct experience with DD hubs so I won't try to advise there.

I do have experience with the Speedict and I just bought a Cycle Analyst for my wife (not installed yet;work in progress)

The Speedict is awesome since you can add things like PAS sensor and throttle control. It can limit current and speed etc. I also love the included logging features. I don't have to use My Tracks or MapMyRide when I'm using the Speedict.

Danny is an awesome fellow and will give you excellent service. He's always updating the Android App and firmware to support our suggestions (e.g. He's changing font color options next release since someone asked)

One drawback is that it requires your phone to be on and using GPS and Bluetooth all the time. Not a big deal in my book. Another thing is smartphone use with gloves can be tough but not impossible.

The Cycle Analyst is a great product as well from what I read. It will serve a good purpose on my wife's bike as I don't expect her to strap her phone to her bike for every ride like I am accustomed to.

 

[zooz]

1. The crystalytes are pretty well regarded motors that would definitely do the trick for you. If the HS series is the one I'm thinking of, they're pretty heavy duty and meant for big time overvolting. You might be better off with a 9c motor, both for your power range and your budget.

So yeah, that was one of the main reasons I wanted to choose Crystalyte HS3540, so in the future if I decide to upgrade my battery I will not have to change my hub motor. Also Crystalyte are pretty badass from what I read what other people say.

2. Not too sure about this one...though I would recommend getting a controller with your motor from the same place. What is your goal in configuring it yourself? It may be possible to get whoever you are ordering it from to do a custom configuration.

Good point. If I go for the Crystalyte controller I can always ask the supplier to pre-configure it for me.

3. Headways are good cells, with fairly high discharge rates, and are apparently pretty easy to put together into packs. It all depends on how much work you want to put in to your project, and how much you'll wind up saving by doing it yourself. I think ampedbikes.com has headway packs pre-assembled. If weight is a concern lipo is the way to go, but do some research before you hop in to that (they can kind of, well...explode).

So one of the main reasons I wanted to build my own battery pack is that I can build it in any shape pretty much, so I can nicely fit it on my bike.

I am still not sure what charger I would need for 16s LiFePO4, but I guess I will try to find more information on ES first or will open a new thread about it.

Not sure about in the UK, but I buy my stuff locally at ebikes.ca, and they ship.

http://www.crystalyte-europe.com/home.php seem to have reasonable prices at least for the motor. And since it is in EU I will not have to pay any tax on top.

Thank you very much for your answers and ideas. Great stuff!

 

[dogman dan]

For the kind of start and stop riding you will have in the big city, I would defintitely not advise the HS motor. Get the HT. Less top speed, but you won't blow your efficiency on every stop or slowdown like you would with the HS motor. HS is born to cruise, and you won't be cruising in the city.

Battery, before you make decisions, look at the Emissions Free website. A very trusted vendor, who makes an excellent 48v A123 battery made to fit perfect in a triangle frame bag.

You might reconsider the motor once you are at E F, and get interested in the Mac 10T motor once you are there. The Macs make a great city motor, since they are larger more powerful gearmotors. Like your current motor, they work great for a quick start, followed by a coast to the next inevitable stop.

Being a guy who wants his phone as dumb as possibe, I favor the CA. The ca is a great tool.

 

[zooz]

For the kind of start and stop riding you will have in the big city, I would defintitely not advise the HS motor. Get the HT. Less top speed, but you won't blow your efficiency on every stop or slowdown like you would with the HS motor. HS is born to cruise, and you won't be cruising in the city.

That is a very good point actually! Given that I am a big guy.

Battery, before you make decisions, look at the Emissions Free website. A very trusted vendor, who makes an excellent 48v A123 battery made to fit perfect in a triangle frame bag.

Thanks! I had a look at the Emissions-free website, they do some nice battery packs for a pretty good price, indeed. I am contacting them.

 

[Drunkskunk]

Since you only want 1k of power, you might as well cross the Crystalyte off your list. its big and powerfull and heavy, and good for 3-5k. A 9 Continents or MXUS is smaller, lighter, and cheaper, and good for 2-3000 watts.

Or as others have sugested, a MAC geared motor may work better for you in the city. A 9C would still be a good choice, though

You could build a battery out of headways, but E F sells a triangle battery that will probably fit your frame. Less hastle, less trouble.

I prefer the CA. I'm sure the Speedist is fine, but I don't want to be tied to my phone any more than I need to be.

 

[zooz]

Since you only want 1k of power, you might as well cross the Crystalyte off your list. its big and powerfull and heavy, and good for 3-5k. A 9 Continents or MXUS is smaller, lighter, and cheaper, and good for 2-3000 watts.

I am not too sure if 9C hub motor is cheaper for where I live (in the UK). I did a quick look and the price works out as per below for me:

Crystalyte HS3540 with 26" rim including shipping - £270 (no import tax, since I can get it within the EU)
9C with 26" rim including shipping and import tax - £380 (buying from ebikes.ca)

Or as others have sugested, a MAC geared motor may work better for you in the city. A 9C would still be a good choice, though

I want to stay away from geared motors, I believe that less moving parts == less trouble.

You could build a battery out of headways, but E F sells a triangle battery that will probably fit your frame. Less hastle, less trouble.

EF has got definitely cool triangle battery pack, but it is very pricey, it is $600 + shipping + import tax, so the total will easily be $800 (over £500). That's hell of a lot of money just for a battery pack. So I would rather build my own pack out of headway cells without a BMS the price would come close to £220 (including shipping, import tax, also various bits and pieces) - more than twice cheaper.

Thank you for your ideas and suggestions, it helps me a lot to figure out what is more suitable for me.

I bet e-bike DIY project is a lot easier and cheaper in the US or CA, but I live in Europe, so sometimes it gets a bit tricky.

 

[zooz]

Just had a look at BMSbattery site, so I could get a 16S Headway 48V 10Ah battery pack which is capable of 50-100A discharge for about £300 including shipping and import tax, not bad I guess.

 

[zooz]

Hey,

Just a quick update on my new project - It is finished finally. \o/

I went for a Crystalyte HS3540 + Crystalyte 48V 40A controller + a direct plug-in Cycle Analyst and a 12s2p Zippy 5000mAh lipo. I am pretty happy with the result I achieved. I know people recommended me to go for a HT3525 rather, because I ride in urban areas more.

Today I did my first round trip to work and back, it was 40km in total, I was pedalling a bit, as well as cruising, so I used 10.5Ah for 40km range in town, which is pretty good I have to say. The CA says 12Wh/km.

More details on my build with pictures: http://endless-sphere.com/forums/viewtopic.php?f=6&t=40892

Thanks for your advice and support. Cheers!

 

[dogman dan]

As long as your battery is not too small, the HS is still fine. In my commuting, I used to have a bit of a problem if I took a different route with too many stop signs, to visit a store downtown. On the normal route, bypassing downtown on a bike trail with few stops, my battery size was fine. Both routes the same length, but if I took the route with stop signs I'd have to ride a few mph slower or I'd run out of battery.

Once I tried a slower speed winding, the efficiency got better, and range improved dramatically. Partly this was the lower top speed, but testing proved that if I rode the fast motor at a slower speed, I still used more battery on all the stops. The slower motor just wastes less heat on the stop signs. This improvement was also measurable on a thermometer on the motor.

So that's why I recomend the slower motors for urban riding. Longer range, cooler motor temps, all good usually. But if you don't have to stop for a mile or more, a fast motor does cruise very nice.

 

[zooz]

As long as your battery is not too small, the HS is still fine. In my commuting, I used to have a bit of a problem if I took a different route with too many stop signs, to visit a store downtown. On the normal route, bypassing downtown on a bike trail with few stops, my battery size was fine. Both routes the same length, but if I took the route with stop signs I'd have to ride a few mph slower or I'd run out of battery.

Once I tried a slower speed winding, the efficiency got better, and range improved dramatically. Partly this was the lower top speed, but testing proved that if I rode the fast motor at a slower speed, I still used more battery on all the stops. The slower motor just wastes less heat on the stop signs. This improvement was also measurable on a thermometer on the motor.

So that's why I recomend the slower motors for urban riding. Longer range, cooler motor temps, all good usually. But if you don't have to stop for a mile or more, a fast motor does cruise very nice.

I totally see what you mean and it makes sense. My commute is about 25 miles round trip. So for 25 miles I use about 10Ah out of 15Ah, that's with a bit of pedaling from dead stops. I will try to find alternative routes where there is less movement going on.