possible to run Q100 24V 328rpm on 36v

[patpatbut]

I have converted my brompton using mwmotor and I must say it is quite powerful motor.

As the top speed is 16mph, I am thinking to increase the top speed a little by using other motor.

Can Q100 24v 328rpm motor be overvolated at 36v? will it get burned easily?

What speed will I be getting afterwards on brompton?

Pat

 

[Deleted member 4366]

I calculate the speed of the 328rpm Q100 in a 16" wheel as as 17mph (no-load), or about 15mph on the road. A 24v one at 36v will be 50% faster, which is 22.5 mph and about 500 rpm. I've run a 24v 201 rpm one at 48v in a 20" wheel, which is about 400 rpm but the same speed as above (22mph). I'm quite heavy at 100kg, and there was no complaint from the motor; however, I didn''t use the maximum power and speed much, so if you're lighter than me, you should be OK, otherwise you would need to be careful when using the power on the hills.Top speed runs are not a problem because the back EMF from the motor prevents high current at speed. The only question is whether the controller is fast enough to spin it up to 500 rpm. It'll probably be OK.

Why don't you just change your 36v battery to 12S lipos, which will give 20% more speed and power? It should work out cheaper. 10aH is only £110 including shipping. 5aH is about £60. Add a charger and connectors and you should have change from £150. Use these packs - three or six for 12S:
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=26801

 

[Scimitar]

Use these packs - three or six for 12S:
Turnigy 5000mAh 4S1P 14.8v 20C hardcase pack (UK Warehouse)

I got one of those last week, for powering a Makita drill. Including the charger, it works out at far less than the price of a comparable capacity Makita battery. As my drill batteries die, I'll just replace them with these. Seems well made and the hard case will protect it from carelessness, a lot.

 

[patpatbut]

I calculate the speed of the 328rpm Q100 in a 16" wheel as as 17mph (no-load), or about 15mph on the road. A 24v one at 36v will be 50% faster, which is 22.5 mph and about 500 rpm. I've run a 24v 201 rpm one at 48v in a 20" wheel, which is about 400 rpm but the same speed as above (22mph). I'm quite heavy at 100kg, and there was no complaint from the motor; however, I didn''t use the maximum power and speed much, so if you're lighter than me, you should be OK, otherwise you would need to be careful when using the power on the hills.Top speed runs are not a problem because the back EMF from the motor prevents high current at speed. The only question is whether the controller is fast enough to spin it up to 500 rpm. It'll probably be OK.

Why don't you just change your 36v battery to 12S lipos, which will give 20% more speed and power? It should work out cheaper. 10aH is only £110 including shipping. 5aH is about £60. Add a charger and connectors and you should have change from £150. Use these packs - three or six for 12S:
Turnigy 5000mAh 4S1P 14.8v 20C hardcase pack (UK Warehouse)

I can not charge the battery outdoor therefore to avoid using the lipo.

Do you know is there any difference between GBK100 and Q100 motor?

Thanks
Pat

 

[Deleted member 4366]

I can not charge the battery outdoor therefore to avoid using the lipo.

Do you know is there any difference between GBK100 and Q100 motor?

Thanks
Pat

They're identical.

 

[keith99]

I calculate the speed of the 328rpm Q100 in a 16" wheel as as 17mph (no-load), or about 15mph on the road. A 24v one at 36v will be 50% faster, which is 22.5 mph and about 500 rpm. I've run a 24v 201 rpm one at 48v in a 20" wheel, which is about 400 rpm but the same speed as above (22mph). I'm quite heavy at 100kg, and there was no complaint from the motor; however, I didn''t use the maximum power and speed much, so if you're lighter than me, you should be OK, otherwise you would need to be careful when using the power on the hills.Top speed runs are not a problem because the back EMF from the motor prevents high current at speed. The only question is whether the controller is fast enough to spin it up to 500 rpm. It'll probably be OK.

Why don't you just change your 36v battery to 12S lipos, which will give 20% more speed and power? It should work out cheaper. 10aH is only £110 including shipping. 5aH is about £60. Add a charger and connectors and you should have change from £150. Use these packs - three or six for 12S:
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=26801

Sorry to butt in on the thread, I dont really understand to much about batterys, how do you get 10amps
from the batterys you have linked too, i read putting into series gives you added voltage but what about amp capacity does that work the same way, I am buying a ready made bike but also want to build my own so need to understand first what is what. so if i wanted to get 36v from the battery you say about how do I acheive this.

Thank you.

Keith.

 

[patpatbut]

They're identical.

Thanks Dave.

Do you know what motor should I use if I want to go 20mph (withload) with my 16" brompton?

The only solution I find is to overvolt 24v 328rpm Q100 motor to 36v without using lipo. In this case, is the efficiency really bad?

One more question, I could not find any supplier that have SWXK5 with 285rpm, do you know why?

Thanks
Pat

 

[Deleted member 4366]

Thanks Dave.

Do you know what motor should I use if I want to go 20mph (withload) with my 16" brompton?

The only solution I find is to overvolt 24v 328rpm Q100 motor to 36v without using lipo. In this case, is the efficiency really bad?

One more question, I could not find any supplier that have SWXK5 with 285rpm, do you know why?

Thanks
Pat

I'm not sure, but you can get other versions in all sorts of rpm on Aliexpress, but I don't knoe whether you can trust those sellers to send you what you ordered, you always get something, but they conveniently forget about key requirements. I just ordered 18 a,p controllers and got 14 amps.

The Q100 motors are cheap enough, so it's worth a punt on one of those. I'm sure I heard 500 rpm somewhere else, so you should be OK, but you need a high-speed controller like the KU65 or whatever GBK supply with it.

 

[Deleted member 4366]

Sorry to butt in on the thread, I dont really understand to much about batterys, how do you get 10amps
from the batterys you have linked too, i read putting into series gives you added voltage but what about amp capacity does that work the same way, I am buying a ready made bike but also want to build my own so need to understand first what is what. so if i wanted to get 36v from the battery you say about how do I acheive this.

Thank you.

Keith.

Don't get amps (a)and amp-hours (aH) mixed up. Amp-hours is how much charge is in the battery similar to the size of your petrol tank in your car. The more aH, the further you go.

Those HK packs are 14.8v and 5aH each, so three of them side by side makes 14.8v and 15aH or put them in a row and you get 44.4v and 5aH, so if you want 44.4v and 10aH, you need six of them.

Actually, their voltage is higher than that and works between 44v and 50v, so you can say 47v average.

Because of their chemistry, they can discharge at a massive rate - over 100 amps for a single pack, which is what makes them dangerous. A normal Li-ion battery of 10aH can only give about 20 amps max.

 

[keith99]

Don't get amps (a)and amp-hours (aH) mixed up. Amp-hours is how much charge is in the battery similar to the size of your petrol tank in your car. The more aH, the further you go.

Those HK packs are 14.8v and 5aH each, so three of them side by side makes 14.8v and 15aH or put them in a row and you get 44.4v and 5aH, so if you want 44.4v and 10aH, you need six of them.

Actually, their voltage is higher than that and works between 44v and 50v, so you can say 47v average.

Because of their chemistry, they can discharge at a massive rate - over 100 amps for a single pack, which is what makes them dangerous. A normal Li-ion battery of 10aH can only give about 20 amps max.

Sorry again to the OP. Thank you D8veh, So let me see if I have this right, I am not good with these things,,if I bought six batterys....then wired 3 of them in series, twice. this would be two seperate packs
of 44v 5amp... so these two 3 packs would then have to be wired in a different way to get the 44v 10amp...is that about right, not sure what that would be called, other than a big bang if I got it wrong.!!

Thank you.

 

[patpatbut]

Sorry again to the OP. Thank you D8veh, So let me see if I have this right, I am not good with these things,,if I bought six batterys....then wired 3 of them in series, twice. this would be two seperate packs
of 44v 5amp... so these two 3 packs would then have to be wired in a different way to get the 44v 10amp...is that about right, not sure what that would be called, other than a big bang if I got it wrong.!!

Thank you.

That is ok. Not to worry. I believe this setup is 3s2p for this pack. Links three of this pack in series and links another exactly the same three packs in parallel.

 

[patpatbut]

Oh forgot to ask one more question the lipo

What is the main different between this pack and your recommendation? (apart from 8ah and 10ah)

ZIPPY Flightmax 8000mAh 6S1P 30C (UK Warehouse)

Pat

 

[Deleted member 4366]

Oh forgot to ask one more question the lipo

What is the main different between this pack and your recommendation? (apart from 8ah and 10ah)

ZIPPY Flightmax 8000mAh 6S1P 30C (UK Warehouse)

Pat

That one is very easy to wire up. You just need a series harness that you can get on Ebay for a couple of quid. you have to remember to disconnect it when charging. The other one needs a 3s2p harness, so more to disconnect/connect when charging, but it works out cheaper, and they're a bit safer being in hard cases. if you drop a pack of the soft ones, they can start burning.

 

[patpatbut]

That one is very easy to wire up. You just need a series harness that you can get on Ebay for a couple of quid. you have to remember to disconnect it when charging. The other one needs a 3s2p harness, so more to disconnect/connect when charging, but it works out cheaper, and they're a bit safer being in hard cases. if you drop a pack of the soft ones, they can start burning.

Thanks. I believe lipo is my future option considering if I can charge it outdoor.

For safely wise, I need the wattmeter like turnigy 130a to monitor the battery usage.
Do you know the way to cut off the battery supply once it reaches the danger low voltage zone?
Or what parameter I need to look at on wattmeter if the lipo nearly reaches that low voltage?

thanks
Pat

 

[flecc]

Sorry again to the OP. Thank you D8veh, So let me see if I have this right, I am not good with these things,,if I bought six batterys....then wired 3 of them in series, twice. this would be two seperate packs
of 44v 5amp... so these two 3 packs would then have to be wired in a different way to get the 44v 10amp...is that about right, not sure what that would be called, other than a big bang if I got it wrong.!!

Thank you.

Yes, that different way to wire the pair of 3 packs is connecting the two positives together and the two negatives together, this being called parallel.

Wiring in series adds up the voltages, wiring in parallel adds up the Ampere hours (Ah):

From Battery University:

Cells in series:

Cells in parallel:

.

 

[Deleted member 4366]

Sorry again to the OP. Thank you D8veh, So let me see if I have this right, I am not good with these things,,if I bought six batterys....then wired 3 of them in series, twice. this would be two seperate packs
of 44v 5amp... so these two 3 packs would then have to be wired in a different way to get the 44v 10amp...is that about right, not sure what that would be called, other than a big bang if I got it wrong.!!

Thank you.

There's no right and wrong way to do it, but I'd wire them in pairs by joining the balance wires and the main wires for a 4S2P brick because they can then be charged as one pack, then I'd join the three pairs in series to make 44.4v. You have to undo the 3S connection harness for charging, but you can get a parallel board that will allow you to charge all three (or more) pairs at the same time.

Another advantage of the 4S packs is that it's easy to add another pair later for even more speed, but with the 6S ones, it's more of a jump.

Keith, you have to be very careful with lipos. If you solder a connector the wrong way, you get a bit more than sparks, although you should live to tell the tale. Also, you should never allow exposed terminals because they are sure to touch something metal, which will get instantly vapourised in a blinding flash. The same when soldering: Make sure that all other wires and connectors are insulated before going on to the next, and always put a female connector on the battery to prevent exposed pins.

 

[patpatbut]

Thanks. I believe lipo is my future option considering if I can charge it outdoor.

For safely wise, I need the wattmeter like turnigy 130a to monitor the battery usage.
Do you know the way to cut off the battery supply once it reaches the danger low voltage zone?
Or what parameter I need to look at on wattmeter if the lipo nearly reaches that low voltage?

thanks
Pat

Can you help me please? Dave

Pat

 

[Deleted member 4366]

You can get lipo alarms, which beep when they go too low. It's best not to run them down too far. A 12S pack is charge to about 50v. In use, they go down evenly until they get to 44v, when they start to go down rapidly. The minimum voltage is 3v per cell, which would be 36v, but they can go down from 44v to 36v in less than a mile, so .It's best to use a wattmeter that shows how many aHs have been used because, you will soon know how many you can use before you fall off the cliff, so you don't have to stand on the edge. A simple voltmeter monitoring the whole pack is the minimum. You'll soon figure out how the voltage goes down, and where it starts to accelerate. Good advice is not to try and eke out a bit more once you're down to 44v.

If you get that wattmeter, it's a good idea to tale the shunts out and mount them on a separate piece of board so that you can have the meter on the handlebars, but don't forget it's not waterproof.

There's no easy way to get automatic shut-off. You have to do it yourself.

 

[keith99]

Thank you D8veh and flecc really interesting and very helpful,best get on and buy stuff, very sorry to op again.!