BMS Battery conversion kit

[Deleted member 4366]

When you file the drop-outs, don't forget to file them deeper as well as wider to keep the motor shaft central, and if you don't file them deep enough, the anti-rotation washers won't be fully in the drop-out, so more likely to spin.

IIRC Scotty has the 9 FET controller (was it 22 amps?). You have the 12 FET controller that can give 40amps - so nearly twice as much torque (maybe). I think I'd be happier if I had a torque arm on at least one side. If you find the throttle a bit fierce, it might be worth getting a couple of the KU93 controllers from BMSbattery because they're not that expensive.

Please keep us updated on your build

 

[catsnapper]

Having tested several BPM motors bolted into a substantial steel truing stand, I was surprised at the amount of reverse force from the axle trying to push it's way out. I've always used torque arms on any BPM installation, whatever the frame material.

I've tried a BPM hub with both the 9 and 12 FET controllers using 36V 15Ah and 20Ah Ping batteries. I've not noticed a huge difference, apart from better hill climbing, but I would guess it's much more noticeable with decent 44V LiPo packs.

Alan

 

[Scottyf]

9fet correct, nice enough to offer decent range and decent amount of hill climbing. And wheelies. Although not power ones only when I pedal.

This was a standard controller with a max current of 20amp. Which is mega low compared to what they can go. I shunted it up to 27amp at one point. And although acceleration was much quicker and hill climbing improved it wasn't really enough to justify itself. I turned it back down to 22amp which is still plenty quick enough.

My bpm is for a 24inch wheel which I have laced into a 28inch wheel. 36v = 20mph @ 44v it's about 24mph with some pedalling.
Again plenty quick enough for me. But it does chew up quite a bit of battery now on my commute.

Can't complain it's really become good fun booming round the city on it and going to work.
I hope you have as much fun as I've had so far and learnt.

 

[aseb]

just for reference there is now a pedelec sensor that connects via the throttle rather than directly to a controller available now. It may help as it will give a wider choice of controllers and can also be fitted as an add on to a non pedelec controller when needed. It may be easier to fit to an existing installation as you only need to access the throttle wiring, not the controller so jumper settings or links to change. I got mine from Lyen (ES).

 

[Deleted member 4366]

Could you post a photo and a link?

 

[Hurricane]

When you file the drop-outs, don't forget to file them deeper as well as wider to keep the motor shaft central, and if you don't file them deep enough, the anti-rotation washers won't be fully in the drop-out, so more likely to spin.

IIRC Scotty has the 9 FET controller (was it 22 amps?). You have the 12 FET controller that can give 40amps - so nearly twice as much torque (maybe). I think I'd be happier if I had a torque arm on at least one side. If you find the throttle a bit fierce, it might be worth getting a couple of the KU93 controllers from BMSbattery because they're not that expensive.

Please keep us updated on your build

Been busy on building first bike. Thought I would start with the most difficult. Turns out it was not that easy. I have managed to fit one torque arm (6mm thick steel) but because I had to space out the disc brake side so that the hydraulic brake caliper would clear the motor I did not have enough axle left for a torque arm.
See couple of photo's.

Pictures by hurricane868 - Photobucket

Waiting now for ping 20ah batteries to arrive. Heard from Ping that they are in Honk Kong. Will try more photo's soon. The snow has now arrived btw.

 

[Deleted member 4366]

That torque arm looks enough. I only have one 6mm one on one side on my rear motor. On my front one I have a 5mm one on one side and a 2,5mm on the other because of the lengths of the axle on each side.

It's not clear from your photos, so is the wheel central to your frame? Have you dished it or will you have to?

 

[Hurricane]

That torque arm looks enough. I only have one 6mm one on one side on my rear motor. On my front one I have a 5mm one on one side and a 2,5mm on the other because of the lengths of the axle on each side.

It's not clear from your photos, so is the wheel central to your frame? Have you dished it or will you have to?

I have made sure the wheel is sitting central in the frame d8veh. Hoping to give it a road test when the snow disappears. Should maybe try it in the snow and see if it leaves two tyre tracks. I have ran a test in my shed using my old 10ah battery and everything is working fine. Certainly a lot quieter and less resistance than the Synergie.

 

[Scottyf]

Usually the rear bpm is about 5mm of central so usually requires a little bit of dishing. But you can get away with it though as it's only 5mm.

I've not use torque arms on my build and it's been fine but safer to have some. I've now ordered some as a just in case. But the dropouts on my bike are generally quite thick and seems to be holding.
Watching the build with interest anyway

 

[Hurricane]

Usually the rear bpm is about 5mm of central so usually requires a little bit of dishing. But you can get away with it though as it's only 5mm.

I've not use torque arms on my build and it's been fine but safer to have some. I've now ordered some as a just in case. But the dropouts on my bike are generally quite thick and seems to be holding.
Watching the build with interest anyway

Sorry to read about your off the other day Scott. Hope you and Marin are okay. Had a couple of cars skidded onto my grass verge last night in the snow so I am not even going to attempt a test run till it clears. Made a right mess of my grass. Should really make a start on bike number two while waiting for batteries.

 

[Hurricane]

The snow has now gone and I have been out for a test run on the new build. Failed miserably. I only get about 500yds and it cut's out. If I then switch off the battery at it's key then back on It works again for about the same distance and cut's out again.

I am using my old 10ah battery until new 20ah Ping arrives on the 350w Bafang motor and KU120 controller so could it just be that the battery is not powerful enough?

Replies would be greatly appreciated.

Alan

 

[banbury frank]

Hi The BMS Is to small in the Battery

You could fit a bigger one what type off battery cell is it li-ion or Lifepo4

Frank

 

[Hurricane]

Hi The BMS Is to small in the Battery

You could fit a bigger one what type off battery cell is it li-ion or Lifepo4

Frank

Thanks for quick reply Frank. It is a lion battery.

 

[banbury frank]

Hi You need one of the following from BMS 20 A continues 40A peak

Smart BMS 5~13 Cells in Series - BMSBATTERY


Frank

 

[Scottyf]

Frank is correct. The 10ah battery the over discharge current is kicking in to protect the cells.
This means when your drawing power from a huge 30 - 40 amp 12 mosfet controller the cells just can't cope.

You need a much better battery like the Ping you have ordered. You'll have to wait really...
Or be hideously gentle with the throttle

 

[catsnapper]

I am using my old 10ah battery until new 20ah Ping arrives on the 350w Bafang motor and KU120 controller so could it just be that the battery is not powerful enough? Alan

The same thing happens with my BPM or Ezee motor using the Li-ion bottle battery. I have to use a KU90 controller with a 20A limit. With the Ping battery all is fine with a KU120 series or 35A Infineon controller.


Alan

 

[Hurricane]

Suppose I will just have to wait then. I was just trying a road test to see if all was okay and it does seem like the battery at not able to cope.

I have the tracking number from Ping and the new batterie's should be here on Monday. We are hoping to head down to York on Tuesday for xmas and was hoping to use the new bike there. Will just have to take the Synergie if battery is not here in time.

Thanks again for your invaluable help.

Alan

 

[Deleted member 4366]

Your 10aH battery has a current limit of probably 20A, so as long as you don't go over that, everything should be OK. It just means that you have to be gentle on the throttle and disconnect the pedal sensor. The pedal sensor gives power according to how fast you pedal. Pedal fast and it'll give the full 35amps.

 

[Hurricane]

At last the Ping 20ah batteries have arrived. Got a scare yesterday whilst tracking the progress for delivery. I was informed that I had to get in touch with Fedex at Stanstead. The packages had failed Customs as they were under declared at a value of 160USD.

I was informed that I had to email my proof of payment so that they could clear Customs. This resulted in a payment due of £205.47!!

I had to decide whether to pay it or send them back. After much foul language to myself I decided to pay the ransom.

Any body else had this experience?

 

[banbury frank]

Hi All FedEx shipments are being looked at we have had shipments held up all is OK as our suppliers don't under declare asking the reason I was told it is counterfeit products they are looking for so if somebody is trying to import A fake product the value shows it up as Fake and it is destroyed




Frank