Ibis Mojo HD and Bafang BBS02 marriage

[Abagrizzli]

What would you say about very compact and light LiIon 48V 20A battery priced at 950 USD? Domestic manufacturer though, which means quality, no shipping, no customs, problem free warranty etc.

The data as shown:
Size: 290 x 140 x 90 mm
Weight: 4.6 kilos
Voltage: 48V
Capacity: 20A/h
Chemistry: Li-Ion
Life expectancy: over 500 cycles
Safety: UL approved (USA)
Suitable for engines: up to 1000W
BMS: included
Overcharge safety: 4.35V-cell / 60.90V-pack
Undercharge safety: 2.75V-cell / 38.50V-pack
Discharge current: 25A
Maximum discharge current: 40A
Nominal charging value: 50.4A


Here's the link for those who use Chrome and can translate the page to English:
http://www.batteries.co.il/index.php/--2881

They have also cheaper Samsung cells for 48V 12Ah and 48V 14.5Ah, priced at 605 and 685 USD accordingly...

Looks good!

Which one? And the price? Is it comparable, even if it's 20% more, I can sustain it, since the customs may charge me VAT, if the package will be detained...

 

[Abagrizzli]

Wow, you are not making this an easy one are you?? I reckon if you mount anything like mine under that main tube it will interfere with the front wheel.

No, I'm not It's a bit of a large project , to build an optimal MTB bike with a kit (and not ready slick design like Haibike), and you guys helping me a lot, 'cos when I read your suggestions and think of it, the final picture becomes a little bit clearer. And even if I don't except those suggestions, it means I found another little bit of a puzzle, which you helped me with. There are a lot of aspects, not just electrical, that I become aware as we continue into this jungle more.

Interfering with the front wheel is definitely a concern, especially on small-sized frames (and this one is definitely small).

I have seen some pics of bikes with the batteries mounted on top of the top tube but looking at those pick always makes me uncomfortable for some strange reason??

Top of the tube won't work for MTB - the battery will be constantly hit with knees while pedalling... Unless it's really in the front, but then it may interfere with the handlebar and put too much weight on the front, which will make the front heavier and as a result climbing rock stairs more dangerous...

What about a beam type rear carrier?? Like:

http://www.torpedo7.com.au/products/DACRSNNMP/title/delta-megarack-post-haste

Which has a limit of 20lbs / 9kg and is 110mm wide and 375mm long in the platform.

On Pauls site:

http://em3ev.com/store/index.php?route=product/product&path=35&product_id=128

The 14 aH rectangle pack battery weighs 3.7kg and is 138mm by 203mm wide. You'd need to build a simple box to protect it but i'd be surprised if you couldn't get it mounted that way for less than 5kg for the battery and box plus 0.52kg for the carrier. That's well within the weight limit for the carrier and i am sure that there are other people on here who would be able to tell you of a carrier like that would give you problems off road??

Beam type also won't work - too much weight on the rear, the rack can fall of or bend, or ruin the dropper seatpost.

I.e. has to be downtube..

After re-reading this, it seems that I sound too negative, but I'm actually not, I'm very thankful for any suggestion

 

[tln]

Which one? And the price? Is it comparable, even if it's 20% more, I can sustain it, since the customs may charge me VAT, if the package will be detained...

The 20Ah one. The others don't have sufficient discharge current.

You can compare to this one:

http://em3ev.com/store/index.php?route=product/product&path=35&product_id=132

That should fit under the downtube in the same configuration as mine. Although thats probably something you should mock up
before commiting $$$

I'd suggest just buying from em3ev because they can supply the motor as well, and the plugs on the battery and motor will work
together out of the box.

 

[Abagrizzli]

Which one? And the price? Is it comparable, even if it's 20% more, I can sustain it, since the customs may charge me VAT, if the package will be detained...

The 20Ah one. The others don't have sufficient discharge current.

You can compare to this one:

http://em3ev.com/store/index.php?route=product/product&path=35&product_id=132

That should fit under the downtube in the same configuration as mine. Although thats probably something you should mock up
before commiting $$$

I'd suggest just buying from em3ev because they can supply the motor as well, and the plugs on the battery and motor will work
together out of the box.

I'm on the fence with this one... I'm about to pull the trigger on the motor in the middle of January. You helped me a lot in choosing the type of the battery. But I don't know where to purchase it yet.

The plus of em3ev - I'm getting the plug'n'play version. The downside - shipping time, custom fees and possible demand for certification with our Institute of Standards for the battery. Although I hope to avoid the latter. After all these the cost may be close to what our supplier demands, plus I have to pay him in full in one payment.

The plus of local supplier - no problems with shipping the battery and certifying it, plus can do several payments... But have to connect the battery by myself.

I'm definitely leaning towards em3ev, unless in these 3 weeks I will learn how to be an electric genius

 

[Abagrizzli]

Now all starts again

Why not 500W or even 350W motor? Given I don't want my wife to hurt herself by mistake, will it be wise to get her less powerful motor? Or just stick with 750W max power and be happy about it not using the whole potential, 'cos it prolongs its life?

 

[astmacca]

After re-reading this, it seems that I sound too negative,

naH!! Its useful bouncing around stuff in discussions like this. Ideas come, go, get picked up knocked back and modified by others who think differently.

Beam type also won't work - too much weight on the rear, the rack can fall of or bend, or ruin the dropper seatpost.

Yeah it is nice for balance having the battery and motor central and low.

I have seen ones where people have actually cut out the top tube or down tube and replaced it with a hollow structural member that houses the battery??

http://ballaratebikes.com/collections/frontpage/products/frame-kits

Or what about a distributed battery pack? I'm thinking the cells all wired up into one BMS, one charging port and one output, but in smaller groups wired together in different locations on the bike?

On this link they have a single battery pack, but its a really nice setup.

http://www.empoweredcycles.com/collections/batteries/products/empowered-cycles-frame-and-battery-case

Yup and they are huge Headway cells.

And you would have to learn battery pack construction or get someone to do it for you.

But it may be one answer to getting a decent size battery on a small full suspension frame?

 

[tln]

Why not 500W or even 350W motor? Given I don't want my wife to hurt herself by mistake, will it be wise to get her less powerful motor? Or just stick with 750W max power and be happy about it not using the whole potential, 'cos it prolongs its life?

I wouldn't call the 750w dangerous... the biggest danger is your wife will leave you in her dust on your rides!
Maybe you need to buy two motors at once?

You might want to go with the less powerful motor if your battery choice doesn't have enough discharge
current. I find I don't use max power on the trails, so a 500w would do me fine; but I really want the full
power for steep 20%+ hills.

 

[DanGT86]

You are not sounding negative, maybe just a little too cautious. I dont think a toptube mounted battery will be as big of a knee clearance issue as you think. Find out the batt dimensions of some of the packs you are shopping for and make a cardboard box template that size. Attach it to the bike and see how much it is in the way.
I was quoted for a 72v 10ah pack with bms that was going to be 75x120x403mm. Seems like that would fit in that triangle especially if it wasn't 72v. I think you will be surprised how much room you have and how small theses packs can be. People claim to have enough clearance with this bag http://endless-sphere.com/forums/viewtopic.php?f=31&t=57623

Split packs may be the goal. You can even run two small packs both with their own bms and connect them in parallel or series. There are plenty of threads here that can help with that. Many have reported that they like the feel of a pack mounted on the front fork. If you put a small pack there and another small pack in the triangle you could fit a lot of capacity.

As far as power, i would get the most powerful kit (750). You dont have to turn it all the way up if its too dangerous but its nice to have the option. If you get the small one and want more power later you have to buy the whole thing over again. The price difference doesnt justify starting with the low power kit. Very few of us have built a bike and wished it had less power.

 

[Abagrizzli]

I wouldn't call the 750w dangerous... the biggest danger is your wife will leave you in her dust on your rides!
Maybe you need to buy two motors at once?

You might want to go with the less powerful motor if your battery choice doesn't have enough discharge
current. I find I don't use max power on the trails, so a 500w would do me fine; but I really want the full
power for steep 20%+ hills.

I don't think there is a danger - I think it's a given

I'm recovering now from the spinal surgery, and getting back to MTBing after 8 months of excruciating pains and lying down. Actually, it will be another 2-3 months before I'll start pedaling again. So I thought to take the wife and start making a riding buddy from her. Now, with this motor, it seems I'm making a more of a coach, who I'll need to chase all the time. Which is good, I presume

About the motor - point taken.

 

[Abagrizzli]

You are not sounding negative, maybe just a little too cautious. I dont think a toptube mounted battery will be as big of a knee clearance issue as you think. Find out the batt dimensions of some of the packs you are shopping for and make a cardboard box template that size. Attach it to the bike and see how much it is in the way.
I was quoted for a 72v 10ah pack with bms that was going to be 75x120x403mm. Seems like that would fit in that triangle especially if it wasn't 72v. I think you will be surprised how much room you have and how small theses packs can be. People claim to have enough clearance with this bag http://endless-sphere.com/forums/viewtopic.php?f=31&t=57623

Split packs may be the goal. You can even run two small packs both with their own bms and connect them in parallel or series. There are plenty of threads here that can help with that. Many have reported that they like the feel of a pack mounted on the front fork. If you put a small pack there and another small pack in the triangle you could fit a lot of capacity.

As far as power, i would get the most powerful kit (750). You dont have to turn it all the way up if its too dangerous but its nice to have the option. If you get the small one and want more power later you have to buy the whole thing over again. The price difference doesnt justify starting with the low power kit. Very few of us have built a bike and wished it had less power.

I thought about split batteries, but since I'm not that electrically or technically skilled, it seems to me like too much for the beginner. So I'll stick with one battery. Top tube is back on the list, I will need to check it actually after I'm getting the battery, so it won't interfere with the dropper post and the knees. Maybe this idea does have a right to exist, after all.

The point about the motor taken. I will stick to 750W, as both of you suggested.

 

[astmacca]

I will stick to 750W, as both of you suggested.

Good idea. I have the 750W de-rated to a nominal 500W by limiting current to 18amps. It has heaps of power if you use the gears properly.

On Batteries. Came across this in another thread:

http://ntsworks.com/battery/mini-48v-battery/

Its certainly compact???

 

[Abagrizzli]

I will stick to 750W, as both of you suggested.

Good idea. I have the 750W de-rated to a nominal 500W by limiting current to 18amps. It has heaps of power if you use the gears properly.

On Batteries. Came across this in another thread:

http://ntsworks.com/battery/mini-48v-battery/

Its certainly compact???

Wow, this battery looks a blast, small and light. Does anybody have any input on this one? Will it be sufficient for BBS 750W?

 

[astmacca]

Will it be sufficient for BBS 750W?

From what i was advised my 48v 11aH with the 29E cells is not really speced up sufficiently to use on the 750W 25amp version of the BBS02. That's based on C rate if i want the pack to last well. Carries the 18amp of the de-rated drive with no prob. And at 18 amp max i figure i'm much less likely to have controller blown FET problems.

However, same pack with different cells can carry the 750W easy. The following from Pauls site where i bought the battery.

We recommend a controller rating of approx ~17A with the 22P pack, ~22A with the 29E pack. The high Power 20R pack can deliver 30A or more, but we recommend the continuous discharge rate is kept within reasonable limits to avoid stressing the BMS.

The 20R pack is rated at 7.6aH. Some info on the 25R's here:

http://endless-sphere.com/forums/viewtopic.php?f=14&t=57291

That nts works pack looks really interesting. I like it that it leave open the upgrade path every few years if higher capacity cells become available in this VERY common format, and also that if a cell goes bad it should findable and fixable much more easily than with a wrapped or RTV'd battery pack. Main prob for me would be cost. AUD$ going through the floor and postage from the US.

How do the dimensions work for you and that small MTB you want to put it on??

 

[Abagrizzli]

Hey guys, can somebody enlighten me please, how does this motor works? I mean can the transferred power be regulated in its stock condition, or is it just on-off going? I mean either it's on full 750W, and then it's off down to zero, or I can regulate the speed at several levels from the throttle and/or display?

 

[Abagrizzli]

Contacted Paul, waiting for his response.

 

[opperpanter]

Maybe you should read soms more first. I would start with the display manual on em3ev site.

 

[Abagrizzli]

Can you please link me to the page? I can't find it on his website.

I read all the time. The problem is that I try to process a lot of info in this short period of time, and get easily confused. I'm sure, most of the things I don't get pretty easy to contain, it's just it is easier when somebody explains it in short and understandable words, than reading 2-3 deep articles...

 

[tln]

Hey guys, can somebody enlighten me please, how does this motor works? I mean can the transferred power be regulated in its stock condition, or is it just on-off going? I mean either it's on full 750W, and then it's off down to zero, or I can regulate the speed at several levels from the throttle and/or display?

Yes, there are a number of power assist levels you can switch to while riding. By default there are 3 levels (as well as a no assist) level. You can configure the display to use up to 9 levels, if you want to be able to finely tune the assist while riding. This is all end-user settable via buttons on the display. At least it is on the C961 (thats the display model I have).

The main thread about the BBS02 has this info but it also has almost 4000 posts! Can't blame you for not finding the info.

BTW you may want to research which display will be in the kit, as there are now a few choices, and some never ones look different and have different levels of adjustability. For the manual, search for "bafang installation pdf" or "bafang C961 pdf" or "bafang C963 pdf" of bafang C965 pdf". I haven't found an english version of the C965 manual yet, but if you compare the C961 and C963 manuals, you'll notice that the C963 max speed limit is 40kph and C961 is 50kph. Some display models have auto-backlight.

Have you decided on a battery?

 

[Abagrizzli]

Thank you, friend. As always you are of huge help )))

Yes, I tried to read that thread, but gave up after 6 or 7 page. Too much stuff irrelevant for me or out of my knowledge.

Concerning the battery. As I mentioned above, I've already wrote to em3ev. Depending on how it will go, I will either go for a foolproof option, getting the easy to instal complete kit from him. If it won't work out for some reason, I will explore other options. For now I'm considering getting a new frame and building a new bike instead of cheap Haro.

 

[opperpanter]

Can you please link me to the page? I can't find it on his website.

I read all the time. The problem is that I try to process a lot of info in this short period of time, and get easily confused. I'm sure, most of the things I don't get pretty easy to contain, it's just it is easier when somebody explains it in short and understandable words, than reading 2-3 deep articles...

Go tot the bbs02 page: http://em3ev.com/store/index.php?route=product/product&product_id=166

Click seconde link from the bottom:
http://1drv.ms/1fdhZM2

 

[Abagrizzli]

Can you please link me to the page? I can't find it on his website.

I read all the time. The problem is that I try to process a lot of info in this short period of time, and get easily confused. I'm sure, most of the things I don't get pretty easy to contain, it's just it is easier when somebody explains it in short and understandable words, than reading 2-3 deep articles...

Go tot the bbs02 page: http://em3ev.com/store/index.php?route=product/product&product_id=166

Click seconde link from the bottom:
http://1drv.ms/1fdhZM2

Thank you, now I see it.

 

[Abagrizzli]

Yes, there are a number of power assist levels you can switch to while riding. By default there are 3 levels (as well as a no assist) level. You can configure the display to use up to 9 levels, if you want to be able to finely tune the assist while riding. This is all end-user settable via buttons on the display. At least it is on the C961 (thats the display

Then what is the NuVinci gear hub everybody is talking about?

 

[tln]

Yes, there are a number of power assist levels you can switch to while riding. By default there are 3 levels (as well as a no assist) level. You can configure the display to use up to 9 levels, if you want to be able to finely tune the assist while riding. This is all end-user settable via buttons on the display. At least it is on the C961 (thats the display

Then what is the NuVinci gear hub everybody is talking about?

Its an internal gear hub, with CVT (continuously variable transmission) gears. Not sure what it has to do with your project

 

[cjh]

I haven't found an english version of the C965 manual yet

Here you go. I have also added the C965 manual for Lectric Cycles as they have a Left and Right buttons as well as the Up and Down buttons.

 

[Abagrizzli]

Excellent, thanks