Can't decide between Q100 or SWXK

[kamaleon]

Hi everybody how's it going

I'm about to build my first kit (hooray!) for my Dahon Jack 26" bike. It has the Alfine 8 IGH which I want to keep so I want to get a front hub motor.
I'm planning to order on greenbikekit.com and battery-wise I thought I'd go for the 36V 10Ah headway battery (with rack).

I can't decide on whether to get the 36V 250W~350W Q100 @ 201rpm or the 36V 250W SWXK @ 201rpm motor. The Q100 is a little bit lighter and marginally shorter height than the Bafang SWXK. Price difference is only $25 but is there any advantage to using the Bafang, is it more torquey? If $25 can get me a little bit more help going uphill than I'll be happy to.
I'm planning on pedalling most of the time anyway and I'm not that much into speed. Is there any difference on top speed without pedalling between these two motors? I guess not since they are both @ 201rpm am I right?
Is there a difference in heating / autonomy or even noise?

Another question, controller related: is it any helpful to upgrade the stock 6 mosfet controller with a 9 one? will it be able to provide more current to any of these motors? I want to buy a spare controller anyway as they're dead cheap in case one goes dead so is there any point in getting a more powerful one?

And if I am to choose the Bafang, there's an option between the SWXK sensorless and the SWXK5 hall effect, what is it exactly?

Thanks in advance.

 

[pacamu]

noticed a new motor here as well that may be suitable also for a front motor

MOutrider_Std Standard RPM Small Geared Front Hub Motor $165.00 USD

http://www.ebikes.ca/store/store_motors.php

 

[d8veh]

Hi everybody how's it going

I'm about to build my first kit (hooray!) for my Dahon Jack 26" bike. It has the Alfine 8 IGH which I want to keep so I want to get a front hub motor.
I'm planning to order on greenbikekit.com and battery-wise I thought I'd go for the 36V 10Ah headway battery (with rack).

I can't decide on whether to get the 36V 250W~350W Q100 @ 201rpm or the 36V 250W SWXK @ 201rpm motor. The Q100 is a little bit lighter and marginally shorter height than the Bafang SWXK. Price difference is only $25 but is there any advantage to using the Bafang, is it more torquey? If $25 can get me a little bit more help going uphill than I'll be happy to.
I'm planning on pedalling most of the time anyway and I'm not that much into speed. Is there any difference on top speed without pedalling between these two motors? I guess not since they are both @ 201rpm am I right?
Is there a difference in heating / autonomy or even noise?

Another question, controller related: is it any helpful to upgrade the stock 6 mosfet controller with a 9 one? will it be able to provide more current to any of these motors? I want to buy a spare controller anyway as they're dead cheap in case one goes dead so is there any point in getting a more powerful one?

And if I am to choose the Bafang, there's an option between the SWXK sensorless and the SWXK5 hall effect, what is it exactly?

Thanks in advance.

Good questions.
The Bafang SWX motors are slightly more robust than the Q100 being a bit larger, so can be tweaked for slightly more power, and spare gears are available for the SWX in case you overdo it. With the same 15 amp controller, the SWX feels like it gives slightly more torque. Whichever one you get, use the hall sensors for smoother, quieter operation.

When choosing a motor, you need to start with the speed you want. You can get the Bafangs in a range of speeds. Have a look on Aliexpress. The only problem there though is that you can't trust them to give the motor that they advertise. If you want to go a bit faster than 201 rpm (25 km/h), try Emailing Kevin Fang of BTN and explain that the speed is an important characteristic. He can put a nice kit together for you:
http://www.aliexpress.com/store/group/36V250W-front-kit/705369_212036629.html

Whatever kit you get, you can increase the hill-climbing by soldering the shunt in the controller (about 1/3 of it). This increases the current from 15 to about 18 amps. The easiest ones to do are the rectangular aluminium box type. Some of the other types are sealed. You need a battery that can give that much current. The Headway battery that you mentioned can, and it's a good battery, but it's relatively heavy. I think I'd go for a 12 or 15aH Li-ion battery for about the same weight.

Try and get a kit with several levels of PAS. That means a controller with a LED or LCD control panel.

 

[kamaleon]

Hi there thanks for your input.

Haha you just showed me a new seller gee I thought I'd had it all figured out with GBK back to scratch it is then
OK regarding speed, I really don't know what to say. I like the idea that the Bafang might be more robust and might be tweaked. But are there any disadvantages against the Q100? Apart the weight. Noise? Does it get hotter? Does it draw more power in a stock configuration?
BTW just to make sure is this SWXK Bafang motor AKA 8FUN Vicky 3?

Regarding the SWXK motors I'm totally lost on the windings and the voltages.
My Dahon Jack has v-brakes and no mountings for disk calipers so it's not like I can afford to go really quick but I guess it might be frustrating to feel like you could go faster but your motor can't take you there. I guess around >30Kmh when needed (with pedalling) would be nice. But I don't want that to be at the expense of good hill climbing. Is there an interest in getting the 24V motors and use them @ 36V? Would I need to get a different 36V controller? Does the KU63 controller come in 24V and 36V? Or it's the same controller and it's the battery's voltage that makes the difference?
If I was to go for more serious power (and noise and weight) I'd go for the BPM climber but I think for my first build I'll stick with a smaller setup.
Battery wise I don't know what to think either... I thought those Headway batteries were marginally more reliable than the "no-name" ones they sell, plus they are *meant* to withstand more cycles than the Li-ion ones. I didn't realize they were heavier. How heavier are we talking about here? I'm so lost! :lol:

I wasn't keen on getting the LED panel as I do'nt have a lot of space on my handlebar and I'm trying to keep my bike a bit discrete without a lot electronics around. I have a couple of turnigy wattmeters that I can plug in when I want to so I was thinking on relying on that for battery monitoring for longer trips. How about getting a 3 speed switch ($1) but I'm not sure how this works - I want to use the PAS so will the 3 speed switch allow me to select 3 levels of assistance just like the LED panel does?

Thanx again... so many questions

 

[kamaleon]

Is it useful to buy the 24V 201rpm Q100 and use it with the KU63 36V controller and 36V battery? Will I then have a faster speed and keep the torque of the 201rpm version? Is that how it works - best of both worlds? Or do you loose torque when you overvolt a motor?

 

[-dg]

I built my wife a bike with the SWXK from greenbikekit.com in a 700c wheel using the 6fet controller and 48 volts (12s lipo). I'm very happy with this configuration and with the motor itself. At 48 volts this give 27 mph no-load speed and about 23 mph on the road with light pedaling. It also climbs pretty well, we have a lot of shortish hills of 6% to 10% around here and it's been great for her. She rides it to work, about 11 miles round trip with about 800 ft of climbing and so far it handles this easily.

I've placed three orders with GBK so far and they have all been good, no problems. I also like that GBK sell spares gears, covers, clutches and the opening tools.

I've weighed and measured the no load speed of a few of the small motors as part of an ongoing project:
[pre]motor code wt KV notes
BPM 10 4.6kg 8.17 0.66 mph/V@700c
SWXH 201 2.9kg 6.59 0.54 mph/V@700c
SWXK 201 2.9kg 6.5 0.54 mph/V@700c
SWXU 201 2.3kg 6.49 0.53 mph/V@700c
Q100 201 2.3kg 6.23 0.51 mph/V@700c[/pre]
The SWXU is marginally lighter than the Q100. I was hoping that the SWXU would come in under 2.0 kg, but no such luck. The SWXH and the SWXK are very similar in weight and speed, I suspect they use the same stator and rotor. All are fairly quiet, but the Q100 is a different higher pitched sound. I think the build quality on the Bafang/8FUN motors may be better than the Q100, it just seems better finished. Trying to load the motor in my fixture (old fork clamped to table) by grabbing it gives me the impression that the SWXH is much stronger than the Q100 and SWXU. That is, I can grab the small ones and almost stop them, and see the current at 14 amps, but it hurts my hands to much to get a reading with the SWXH. Given that the SWXK is only 0.6 kg heavier than the SWXU/Q100, I would not get any more small motors, the mid-size ones seem much more capable.

I'll know more when I have these in bikes and have some experience with them.

 

[kamaleon]

Hi

THanks for your great feedback. You know since I can't decide, I'm going to buy the two of them :lol:
I'm bulding two bikes, one for me, one for my GF so then we'll see who gets to the top of the hill faster
I don't want to get a 48V battery since they're bulkier and more expensive, so I wonder how fast the 201rpm 36V Q100 and the SWXK5 will go with light pedalling on the flat. If they go around ~30 kmh and still have good climbing then I'll be very happy. We both have 26" wheels though.

My only previous experience ever taking an ebike on a short trip was with a really heavy bike w/ Sanyo 24V 250W front hub motor (I think it's the Rabbit Tool motor) so I guess I can't go wrong with either the Q100 or the SWXK5... :wink:

In the future should I need a different beast I'll probably go for a Bafang BPM one in a more serious configuration.

 

[-dg]

You know since I can't decide, I'm going to buy the two of them ...
I'm bulding two bikes, one for me, one for my GF so then we'll see who gets to the top of the hill faster ...
I don't want to get a 48V battery since they're bulkier and more expensive, so I wonder how fast the 201rpm 36V Q100 and the SWXK5 will go with light pedalling on the flat. If they go around ~30 kmh and still have good climbing then I'll be very happy. We both have 26" wheels though.

I have no doubt at all that the SWXK will climb hills better. I don't recommend the 201 rpm motors on 36 V. If you do use 36 V you will get about 25 kmh on level ground with light pedaling with 26" wheels. Up to you, but I would prefer to go a little faster. On 48 V you will get about 35 kmh.
You could go with the fast wind motors, but then you will lose hill climbing capacity. I strongly suggest more than 36 volts instead.

I bought the SWXK first and and am totally satisfied with it. I then bought an SWXU and a Q100 for a different pair of bikes that I wanted to make as light as possible. I got both because one is for a friend on a similar bike, and we could not decide between them. Now that we have them in hand and have compared them on the bench fixture (not yet in the bikes) we both think the SWXK would have been a better choice. We are still hopeful that the Q100 and SWXU will be strong enough for the application, but we have some doubts about that. We know the SWXK is up to it.

 

[kamaleon]

OK thanks for that.
25kmh on 26" is that all? Dang...
I definetly don't want to go for the fast wind as I really need decent climbing

I thought I'd get one Q100 for my girlfriend because
a) it's marginally cheaper
b) she doesn't want to go very fast
c) she'll use the bike less than me
d) the Q100 is a bit lighter

but i might follow your advice and get 2 SWXKs

Does the KU63 controller handle 48V? How do you use them motors @ 48V or 12S or whatever? I'm looking into getting the laced wheel kits from GBK or BMSBatt or whatever and these come with the stock controller - I wanted to use the KU63 with 3 speed button

 

[d8veh]

Lots of questions to answer there. I'll try a few. The 201 rpm motors do 15mph (25km/h) at their nominal voltage (say 36v), but the actual battery voltage is higher. A 36v battery spends most of its time round about 40v, so the speed is about 10% higher.

The Bafang motors are more robust than the Q100, and give a little more torque, but are not quite as smooth, and are a bit noisier at high power.

You can use most 24v controllers at 36v without modification.
24v motors will spin 50% faster at 36v, but they don't really have the power to reach that speed, so end up working inefficiently. you should only do that if you're light-weight and/or can pedal hard. That sort of setup suits a roadbike. It can also be used on bikes with small wheels.

Most 36v controllers can handle 12S (nominal 44v, actual 48v) with no modification, but not a 48v battey, which is actually as high as 54v, although some can still handle it.

The ideal 250w motor is 230 to 250rpm comparing power to speed. You can also bump up the speed by using a battery booster pack. The idea is to use two additional cell strings in a separate pack to increase the voltage (and speed) by 20%. You need to charge them separately with a lipo charger, so a bit more messing about, but safer than using lipos. Some BMSs have the 13 pin connector with two pins redundant, so if you're lucky, you could wire in the cells to the BMS, and the BMSBattery chargers are adjustable for voltage, so you could get a plug-and-play system.

A 10aH Headway battery weighs about the same as a 15aH Li-ion one, which costs the same. The Headway one can go more charge cycles, but there would be less charge cycles for the 15aH one because it can go further.

You need an LED or LCD panel to get the variable levels of PAS. Without one, you get full power whenever you're pedalling, which is inefficient and problematic when riding in tight spaces. The three-speed-switch normally only limits the throttle, not the PAS.

 

[kamaleon]

Cheers d8veh

OK so how do you guys run your SWXs with a 48V battery (not a 12S Lipo)? Which controller is needed for that setup? That can be bought from BMSBattery.com?

Your li-ion vs headway comparison is spot on and is good food for thought. Weight being equal I guess I'd still go for more charging cycles on the long term.

Regarding the LED panel vs 3 speed switch issue I'm still confused: so what good is the 3 speed switch? Are you saying it'll provide full power always?
I thought it'd mimic the LED panel with multiple PAS assistance levels, isn't that the case?
So what you're saying is that without the LED panel the PAS will always be at its maximum not allowing soft starts? Sorry I'm finding it hard to understand

BTW regarding batteries still. Initially I was going to order through GBK because shipping was supposedly cheaper but as it turns out BMSBattery seems to have better quotes. Anyway with BMSBattery i get a quote $100 more expensive if I order their no name 36V10Ah LiFePo4 batteries with rack instead of the Headway with rack ones so that's very strange!

Hey d8veh I've seen you have a couple of Rinky Dink photos on a photobucket album of yours - have you seen it recently?
I pedalled for it at the Big Green Gathering back in the late 90s - great stuff! If you're into that kind of stuff you might want to hear about my pedal powered generator?

 

[d8veh]

For a 48v battery, you really need a 48v controller. but 12S lipos can run on a 36v controller. The problem is that small 48v controllers are not so easy to find. You can get them, but you have to search a bit and/or be prepared to pay more.

The LED panel allows three levels of PAS. Level one is low power, level three is maximum power. Whichever one you set, that's the power you get when you pedal. Without the panel, you only get max power when you pedal

The three-speed switch is a separate connector. It's a bit of a mystery how it works. It only affects the throttle. There's three wires to it. With none connected, you get normal speed from the throttle. With the middle wire connected to the left, it restricts the throttle speed somehow, which is a complete waste of time on anything less than a 500w motor because you can turn down the throttle to decrease speed. When you connect the middle to the right, you get a speed boost. I believe that it changes the pulse timing somehow. Inmy experience, you only get the speed boost when running with hall sensors in the motor. The speed increase is not that much, but it depends on which motor you have. 2mph gain is common. Other controllers work differently. You can program the three speed switch to give whatever percentage power you want.

You must be in the UK then. In that case, have a look at this:
http://www.pedelecs.co.uk/forum/classifieds/15157-mxus-motors-lcd-display-controllers.html
Many people have the same aims as yourself, and it's really difficult to find the right combination of bits, so when I was in China, I sourced some parts that would meet those requirements. Most of the bits arrived yesterday, but like always when you deal with these Chinese guys, you don't get what you ordered. I'm still waiting for PAS sensors and brake sensors, but I have the motors and controllers. I'll be building a bike shortly to test everything. The motors are really nice, but need building into a wheel.

 

[kamaleon]

Hi mate
Thanks for your help.
So I guess there's no alternative to the LED panel to select three different levels of PAS huh...

Actually I'm in France. Is that MXUS motor you are selling the XF model?
I just saw a webshop from Spain, Ciclotek, selling MXUS XF kits. I wonder how they compare with the Q100 and SWXK, if I read you correctly, they are have the same dimensions and same weight as a SWXK, but they are stronger?
According to that shop they come in different rpms too?
http://www.motorparabicicleta.com/2011/11/motor-muxs.html
http://www.motorparabicicleta.com/2012/01/las-revoluciones-y-la-velocidad-de-los.html

 

[d8veh]

Yes, the motors I have are marked XF04. They're 270rpm and the cassette version. I've done a side-by-side comparison with a Bafang SWXB.

The Bafang was 36v 22 amps. The MXUS 36v 19 amps. Both riders the same weight. In all circumstances (different speeds, hills, etc) the MXUS pulled away from the Bafang significantly. I think the Bafang must be saturated with that much current, and it felt a little over-worked. The MXUS felt like it could handle a lot more. I''ll try it with a 22 amp controller next.

The MXUS would blitz the Q100 in a similar test.

I did some measurements, which shows that the MXUS is slightly wider and larger diameter than the Bafangs on the outside, although the spoke flanges are nearly the same.

 

[kamaleon]

Good stuff.
But in my case if I'm using a li-ion 36V 10Ah battery which can't provide too much current, and a 6 mosfet controller would it still have advantage over the bafang and Q100?

 

[d8veh]

It's difficult to say. I don't think that there would be much difference. The Q100 has less mid-range torque, but can run at a lower speed . My MXUS is a higher speed motor, so runs better with a few more amps. I think the main thing for you is to choose a motor that goes at the speed you want bearing in mind that a low powered motor can't sustain high speeds.

 

[kamaleon]

So the MXUS only really shines say with 12S lipos and 9 mosfet controller... is that correct?

 

[d8veh]

So the MXUS only really shines say with 12S lipos and 9 mosfet controller... is that correct?

I started with a 14 amp controller, and it was similar to the other 250w motors. I then soldered the shunt in the controller to take it up to 19 amps, which made it a lot better. We have a short 14% test hill. It still couldn't get my 100kg up without pedalling. I then switched to a 22 amp 9FET controller. Now it feels even better, and can just get me up that hill without pedalling, but only with a fully charged battery. Acceleration is still slow compared with a 500w Bafang, but it creeps up to 20mph on the flat, and then will go faster in the right conditions. I can imagine that 12S lipos might be too much for it at that current. I'll try it tomorrow to see.

 

[kamaleon]

Which battery exactly did you use for that test then?

 

[ezzpete]

for what it's worth coming from a newbie, here's my impression of the Q100. I bought a 36v kit from GBK, and have been using it for about 3 weeks. i got the 8.8 ah bottle batt with mine. first thing is i'd recommend a different battery, as the one i got seems to lose quite a bit of power after about 3 miles. but that may be mostly my fault because after finding out how much fun it is to not peddle i mostly don't.

as for the motor and controller, i'm very happy with their functioning. the motor is quiet and runs good. also dealing with GBK was easy and fast. all that said, if i were to do it again i'd go for a more powerful motor (500-1000 watts) because even if you think you are going to peddle and don't want to go fast, as i did, i'm pretty sure that will change. so basically it would be more economical to spend more at the start. and about the 3 speed switch. i have one but never use it, and on my kit anyway, it only gives 2 speeds, normal and slower, and i don't want to go slower, i want to go faster.

 

[kamaleon]

Thanks for your input

Right now I'm looking into getting this battery
http://www.bmsbattery.com/36v/183-36v-10ah-lithium-ion-electric-bicycle-battery-pack.html
It's my first build so I want to keep it simple, light, and cheap... second build will probably use RC Lipos once I get the hang of it
It's quoted for 15A discharge so that should be ok for the Q100 / SWXK with stock controller? :?
For roughly 7 bucks more I could get this one plus a charger
http://www.bmsbattery.com/packs/558-36v-10ah-38120-lifepo4-battery-12-cells-ebike-battery-pack.html
But it's 1.5Kgs more and 1Ah less... :?
Another interesting one using 38120S cells
http://www.bmsbattery.com/36v/495-36v-10ah-lithium-ion-electric-bicycle-battery-pack.html
But at 3Kgs only that figure surely must be wrong

I'm not considering the batteries with rack kits anymore as these will increase shipping costs on over $100 more

 

[d8veh]

Which battery exactly did you use for that test then?

I was using the BMSBattery 36v 20aH shrinktube battery.

Battery choice is always difficult. The ones with Headway (cylindrical) cells are good but heavy. The LiFePO4 shrinktube one has pouch cells which is why it's lighter. A 10aH battery can give 10 amps for a long time, but will sag a bit when you use more current. If you found that standard 15 amp controller didn't give enough torque, so you wanted to increase the current by soldering the shunt, the 10aH battery might be a bit under-rated (apart from the heavier Headway one), so I'd normally go for a 12aH one, where there's only a small additional weight. The 15aH shrink-tube one is also fairly light for it's size, so that also makes a good choice. Only if light-weight is fundamental should you go down to 10aH or less, in which case maybe this one:
http://www.bmsbattery.com/36v/183-36v-10ah-lithium-ion-electric-bicycle-battery-pack.html

 

[kamaleon]

Hi m8

36V 20Ah is 15A discharge so yes it would sag under that load. Like the 10Ah ones that I want to buy.
I think I'll stay on the safe side and try not to push these bikes too much I guess around 10A maximum with short bursts over that should be reasonable for us (me and my girlfriend).

I don't see a shrink tube 36V12Ah Li-ion only LiFePO4 which makes it much heavier at 5Kgs
So is the pouch Headway really that light? 3Kgs??

The one from your link is the one I wanna get.

The reason for me wanting to get this one is because it's fairly cheap and I'll only use it 2 months a year maximum (these first 2 builds will be summer bikes) so it's no point spending more money on something that might go dead after a while...
The other reason is that all other batteries (with racks) are quoted for $100 more when calculating shipping costs!

 

[d8veh]

Hi m8

36V 20Ah is 15A discharge so yes it would sag under that load. Like the 10Ah ones that I want to buy.
I think I'll stay on the safe side and try not to push these bikes too much I guess around 10A maximum with short bursts over that should be reasonable for us (me and my girlfriend).

I don't see a shrink tube 36V12Ah Li-ion only LiFePO4 which makes it much heavier at 5Kgs
So is the pouch Headway really that light? 3Kgs??

The one from your link is the one I wanna get.

The reason for me wanting to get this one is because it's fairly cheap and I'll only use it 2 months a year maximum (these first 2 builds will be summer bikes) so it's no point spending more money on something that might go dead after a while...
The other reason is that all other batteries (with racks) are quoted for $100 more when calculating shipping costs!

The reason that they say 15 amps continuous for the 36v 20aH battery is because that's the rating of the BMS. The cells can give a lot more. I use these batteries on some of my bikes with 30 amp controllers, and they're very good, with no significant sag.

I understand the problem with the rack batteries, but just in case you didn't notice, these ones have a plate that fits to any rack, so very easy and tidy to fit:
http://www.bmsbattery.com/36v/232-36v-15ah-lithium-ion-electric-bicycle-battery-pack.html

I ran my MXUS motor today with 12S lipos and 22 amps. It's now pretty lively. It accelerated my 100kg steadily all the way up my road, which is about 4% slope. reaching about 20mph without pedalling. It can manage our short 14% test hill, but I'd say 10% is about the limit for long hills .

 

[kamaleon]

were you using a KU93 controller? do you think that one's suitable? I can get a spare one now from BMSBattery in case I go for an MXUS kit later on