BPM Bike Kits?

[d8veh]

Im about to order a similar setup as you, and i have a couple od questions:

Why the extra chargers? there is one included in the conversion kit.
Why the extra brake grips and throttles, also these are included in conversion the kit?
What will the difference be with the 500W controller compared to the A 450W 9Mosfets universal controller included in the conversion kit?

Would the same package be suitable for a standard citybike with steelfork Like this one:

Your bike is perfectly suitable. A rear motor will probably be best. You could mount that 12aH battery on your rack or, betterif you can manage it, in the triangle.

The kit includes motor (in wheel), throttle, grips, levers, controller and pedal sensor. You order the battery separately and most have chargers with them, but not the 12aH headway battery. Additionally, you need at least one torque arm (unless you want to make your own) and a free-wheel set from somewhere.

It's a good idea to get a spare throttle because they cost next to nothing with your order, but if you have to buy one later on its own, they're relatively expensive. The same with pedal sensors. They're so cheap that it's easier to buy a spare in case you move your kit to another bike later, and it saves having to take the crank off to remove the old pedal sensor.

The 500w controller is bigger and has 12 FETs and gives about 30 amps. The 450w one has 9FETs and gives 22 amps as supplied. My code 13 BPM motor will drag my 100kg up any hill at 30 amps. If you're lighter, you might find 25 amps better. I use the KU93 controller with the shunt soldered to get it up to 30 amps because I prefer the smaller size. It only gets warm if I use continuous maximum speed.

That 12aH battery mounts nicely on a rack in a football boot bag. go down to your local sports shop and get the bag of your choice to match your bike for about a fiver; cut a piece of plywood the size of the base; bolt it to your rack with flat-headed coach bolts. This makes quite a neat stealthy solution that's reasonably tamper-proof. If you get one with an extra zip pouch on the side, you can feed through your charge wire/connector, use one of those remote battery switches from Jeremy harris, then you can zip-tie the main zip to make it pretty secure. There's also room for the controller in there as well.

 

[Confab]

Im about to order a similar setup as you, and i have a couple od questions:

Why the extra chargers? there is one included in the conversion kit.
Why the extra brake grips and throttles, also these are included in conversion the kit?
What will the difference be with the 500W controller compared to the A 450W 9Mosfets universal controller included in the conversion kit?

As d8veh mentioned, there isn't a charger with that battery. Because of the high shipping costs (€200) I decided that a spare BMS (actually two spare BMSes, as there's one with the Headway battery), spare charger, throttles and ebrakes would be smart as they're the components most likely to fail, and besides they cost hardly anything extra. I decided on the more powerful BMS as it will hopefully be more reliable and stay cooler longer, plus it'll give me better acceleration if I want it in future.

Basically, I don't want to have a dead ebike just because I was too cheap to spend an extra €60 on spares.

 

[d8veh]

I just noticed that It looks like yor got hub gears on that bike (if any gears) and I can't see the back brake. Is it a back-pedal brake. If it is, it would be much simpler to fit a front motor.

 

[manneokoko]

Yes, its a back pedal brake bike. Do you think it would be OK with a 36V 350W Bafang front motor on this bike? Or is it a risk that the fork dropout is not strong enough? Its a steel fork.

 

[d8veh]

Yes, its a back pedal brake bike. Do you think it would be OK with a 36V 350W Bafang front motor on this bike? Or is it a risk that the fork dropout is not strong enough? Its a steel fork.

It should be OK with a good torque arm on one side and maybe two torque arms if you use the KU123 controller for more torque. Sometimes the axle isn't long enough on one side to fit the ready-made torque arms.

 

[Confab]

Just got an email from BMS Battery, apparently they're out of thumb throttles, so a half twist will be included instead. Oh well, at least they asked. Anyone know if the half-twist rotates away or towards the rider for power? Might glue on a bit of plastic for a makeshift thumb throttle. At least it's a sign that the order might be ready for shipping.

Just remembered I have twist shifters so will probably need to swap them out for thumb shifters. Crap.

 

[d8veh]

The half-throttles rotate towards you , but you can get LH and RH ones. If you want a thumb throttle, I have a spare one that I haven't used, which I'm willing to for your half-throttle. If you want it, send me your address by PM.

 

[Confab]

The half-throttles rotate towards you , but you can get LH and RH ones. If you want a thumb throttle, I have a spare one that I haven't used, which I'm willing to for your half-throttle. If you want it, send me your address by PM.

PM sent, thanks.

 

[miuan]

buy a thumb throttle from tncscooters or whoever on ebay gives you the best deal.

 

[Confab]

Since the Headway pack will have a BMS already installed, could I open the battery and swap it for the KU123 BMS? How complex would that be? I can solder and use a multimeter, but that's about the extent of my knowledge.

 

[d8veh]

The BMS in the battery looks after charging and balancing as well as low voltage control. The controller only has LVC, so the answer is a definite no!. What's on your mind with that question?

 

[Confab]

The BMS in the battery looks after charging and balancing as well as low voltage control. The controller only has LVC, so the answer is a definite no!. What's on your mind with that question?

Well it means that it was a waste of money buy two spare BMSes when they can't be used with the Headway battery pack. What happens if the Headway BMS fails? Or am I getting the wrong end of the stick entirely? I've heard that the Headway BMS is not very reliable.

 

[dnmun]

you bot two extra BMSs from them along with the battery and motor?

your battery should have a BMS on it now, so you should not need to replace it.

if you bot extra BMSs then you could use them also if you wanted. just take out the one that came with the battery and insert one you bot for a spare. wiring is simple.

 

[d8veh]

When you ordered the battery, there was a chance to select a higher rated BMS. Default is 15 -30 amps, options are 30 -60 and 50 - 100 amps. Provided you selected the right one for how much current you plan to run at, you shouldn't have any problems. BMSs should normally be very reliable as long as you don't run over their maximum rating. The controller doesn't have any sort of BMS. The only thing it does is measure the battery voltage, and if the microprocessor sees the level go below its programmed minimum, it switches off.

 

[Confab]

When you ordered the battery, there was a chance to select a higher rated BMS. Default is 15 -30 amps, options are 30 -60 and 50 - 100 amps. Provided you selected the right one for how much current you plan to run at, you shouldn't have any problems. BMSs should normally be very reliable as long as you don't run over their maximum rating. The controller doesn't have any sort of BMS. The only thing it does is measure the battery voltage, and if the microprocessor sees the level go below its programmed minimum, it switches off.

Thanks for that, I understand now. I ordered the 30-60A controller for the Headway.

 

[amigafan2003]

Thanks for that, I understand now. I ordered the 30-60A controller for the Headway.

You mean BMS?


BMS - battery management system - connects all the cells together on the battery to enable HVC, LVC, limit discharge rates and to balance the cells.
Controller - the little box of magic that connects between the battery and the motor that makes your motor spin

 

[Confab]

You mean BMS?

BMS - battery management system - connects all the cells together on the battery to enable HVC, LVC, limit discharge rates and to balance the cells.
Controller - the little box of magic that connects between the battery and the motor that makes your motor spin

Aha. Now I begin to understand. I ordered this http://www.bmsbattery.com/packs/154-36v-12ah-38140-lifepo4-battery-12-cells-ebike-battery-pack.html with the 30-60A discharge current for my BPM 350W motor. It has a built in BMS. I assumed that the controller and BMS were the same thing. So I will have (in a few days) two controllers, a KU93 and KU123. Which would you recommend I use first?

 

[Confab]

Well, the kit arrived yesterday (code 13 BPM 350w). I've fitted the wheel/motor with torque arm, unfortunately there's only space for one torque arm with torque washers installed on both sides. The cable from the motor to the controller is too short, so I'll have to mount the controller elsewhere. Thankfully I didn't get the Falcon framebag as the battery doesn't fit in the frame anyway!

I haven't been able to run it, as the Headway battery connection is not compatible with either controller, so I'll have to solder on the connector supplied. That's fine as I have to solder in the watt meter and increase the length of the wires anyway. One of the chargers has a rattle in it, so I won't use it until I've sorted that.

 

[steelman]

how did that motor work out im interested

 

[chvidgov.bc.ca]

I've got two of the BMSBattery Headway packs, one a 10hr smaller pack, and the larger 15 Ahr pack. One I made myself from BMSBattery parts, and the other premade from BMSBattery. I had to alter the larger one's configuration as I wanted 6 6 4 configuration rather than 8 8 configuration - it comes as 8 8 with the BMS on the end, rather than 6 6 4 with the BMS in the cavity, which changes the pack shape to be shorter,which I needed. It was moderately easy to do, taking the orange plastic pieces off etc.

I like these BMSes on these packs - they seem to balance really well, and run cool. In fact I like them better than the Signalab ones, and they keep the Headways at just over 58 volts when charged and balanced. Both of them have had no issues in hundreds of miles on the larger and smaller packs.Note: this is not what is generally known as a "Headway" BMS. It is a BMSBattery BMS for Headways, and has seemingly proven reliable, unlike the "Headway BMS" for Headways (seemingly from accounts).

I've gradually come to prefer these packs above the PING due to the supposed 3C character of the cells, and the modularity and no worries BMS, easy to replace a cell if necessary.

They are a bit heavier than my Pings, but I like them. The pack connections seem pretty robust too, other than the odd end-cell bolt loose if they are not heavily tightened at first.