Hi im looking to buy a e-bike kit with a 1000w front wheel hub motor for a 20'' wheel, but i dont know what im buying really, are there any makes or models to avoid? what are the good makes or most reliable ones? any help would be great, thanks
best kits to buy for powered wheelchair
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m@Robertson
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A front wheel motor puts a whole lot of stress on the fork dropouts. Torque arms are required to make the fork safe, and you can't do that with an aftermarket kit of more than minimal power, and a suspension fork.
The typical consumer looks at watts as the measure of a powerful hub, but really that is meaningless. Wattage ratings on motors are only indicative of how much current they can take over a long period without cooking themselves inside. The measure that REALLY matters is the amperage of the controller. More amps = more acceleration. In (oversimplified but largely accurate in terms of the feel of it) automotive terms you can equate controller amps to torque, with more amps equalling more torque.
And on the subject of torque, again you ignore the watts and look at the torque output of the motor. A direct drive motor would be something like a max of 45 Nm. A geared hub could be as high as 80-95 Nm (and thats too much for a front fork).
A 20" front geared hub using a Bafang G020 500w motor backed by a 25a controller is going to accelerate at its full rating of 45Nm. Even using two torque arms, its wise to reduce the power on that motor by setting it to slow-start, which still gives you full amps but rolls the power on via a gentler curve. Dropouts can snap even on a steel fork even with torque arms in play.
Not the answer to your question but things you need to think about if you are going to do a front motor. Done right, they are not simpler than a rear motor (which should also use torque arms for the same reasons, but frames tend to be perfectly safe once so reinforced).
The typical consumer looks at watts as the measure of a powerful hub, but really that is meaningless. Wattage ratings on motors are only indicative of how much current they can take over a long period without cooking themselves inside. The measure that REALLY matters is the amperage of the controller. More amps = more acceleration. In (oversimplified but largely accurate in terms of the feel of it) automotive terms you can equate controller amps to torque, with more amps equalling more torque.
And on the subject of torque, again you ignore the watts and look at the torque output of the motor. A direct drive motor would be something like a max of 45 Nm. A geared hub could be as high as 80-95 Nm (and thats too much for a front fork).
A 20" front geared hub using a Bafang G020 500w motor backed by a 25a controller is going to accelerate at its full rating of 45Nm. Even using two torque arms, its wise to reduce the power on that motor by setting it to slow-start, which still gives you full amps but rolls the power on via a gentler curve. Dropouts can snap even on a steel fork even with torque arms in play.
Not the answer to your question but things you need to think about if you are going to do a front motor. Done right, they are not simpler than a rear motor (which should also use torque arms for the same reasons, but frames tend to be perfectly safe once so reinforced).
thanks for your quick and detailed reply, ill be honest with you as you seem to be knowledgeable, im in a wheelchair and they brought out a 2 wheeled addon to your chair, i can link it, but its £6k i thought i could just make my own with the help of my brother to weld etc, so im looking at what i can get to replicate something like this but at a fraction of the price, https://www.trirideitalia.com/en-gb/mtw-multi-traction-wheelchair/mtw-trekking-power/
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All wheel drive wheelchair!
Now there we go, that is awesome!
You can make something but not quite like that...or if you have the cash and knowledge and the time i think you can!
So if you and yur brother were to think about fabricating something to lift the front wheels and use the front of a bike to hook it yup to yur wheelchair ....oh man my mind ir running wild
Some good ideas here to look at ..just remember..use your mind...be creative yet SAFE...make sense?
https://duckduckgo.com/?q=diy+electric+wheelchair+conversion+kit&t=ffab&ia=web
Take alot of pics and show us so we can chime in and tell you what we see and think
Now there we go, that is awesome!
You can make something but not quite like that...or if you have the cash and knowledge and the time i think you can!
So if you and yur brother were to think about fabricating something to lift the front wheels and use the front of a bike to hook it yup to yur wheelchair ....oh man my mind ir running wild
Some good ideas here to look at ..just remember..use your mind...be creative yet SAFE...make sense?
https://duckduckgo.com/?q=diy+electric+wheelchair+conversion+kit&t=ffab&ia=web
Take alot of pics and show us so we can chime in and tell you what we see and think
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@m@Robertson will come around now that he knows what you are trying to do with your cicumstances 
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Mate!
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Just you and your brother look at this and copy it... https://www.ebay.com/itm/1663635228...1291&msclkid=5d4ad182499a1419f845b7962d03a2f2
Links to eBay may include affiliate code. If you click on an eBay link and make a purchase, this forum may earn a small commission.
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ya wont want rear wheel assist mate...yull be dooin wheelies LOL WEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE
lol
Please keep us posted as this build progresses
lol
Please keep us posted as this build progresses
thanks i have the front part, but that only gets me so far, i still cant go on the beach as i just dig a hole in the sand i need the powered wheels to push not pull my weight, also going up steep hills forces me to go in reverse, i have this atm https://www.trirideitalia.com/en-gb/power-device/special-l14/ its the 48v version, it goes well around 20mph but like i said i cant go on the beach with my family so i need rear wheel drive, and i dont want to buy the wrong things so thats why im here for help
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on the beach? yur askin alot bud lol
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Rear wheel drive son the beach will feck yas mate... fat tire front wheel attatchment... just my opinion.
Lets see what others have to say and be sure to post this on other ebike forums mate because i have heard quite a bit about this situation
and seen or think i've seen some good results.
Keep us posted please
Lets see what others have to say and be sure to post this on other ebike forums mate because i have heard quite a bit about this situation
and seen or think i've seen some good results.
Keep us posted please
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This is gonna sound weird like ima nutcase
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ok, could yas lock the WC wheels then have snowboards undewr wheels....being pulled slowly by the front 20" electric wheel...?
There is alot to be absorbed here...we prolly need moar info as well.... , we need m@Robertson right about now, ima stumped for now
There is alot to be absorbed here...we prolly need moar info as well.... , we need m@Robertson right about now, ima stumped for now
the one im trying to replicate can do it heres a video but i dont have to be blasting around like that, just getting onto the beach and going along it would be a good start, plus its not just meant for the beach me and my wife go on bike rides down gravel paths etc so it would help with that
m@Robertson
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@FiNGaz On that web site you linked, you can see the torque arms they used. The little black bolt-on bits at the end of the fork.
Here are a couple of pics of the 20" front motor wheels I am using. I HIGHLY recommend the Maxxis Minion 20x2.40" tire as one that has a strong casing and can take just about anything you throw at it. I use mine to navigate sand and allow me a mild off-road capability. You'll notice I am using a physically smaller hub motor. That is because its what is called a geared hub. The type of motor the other guys are using is called a Direct Drive motor. They are maintenance free, but they need more power to deliver the same level of torque output. Thats why you will probably see 1000w on them but not get any more than the same 45 Nm of both of them. Geared hubs provide better performance when the going gets tough (i.e. dirt or low rolling hills).
But know that a hub motor is never in its element in dirt or hills. The performance you see in that video is for an awd chair and the reason they can do those things is because all of the wheels are powered and they have distributed traction. You won't be able to come remotely close to that with a single front motor so hopefully you already have the rear wheels powered.
Some things about using a bigger tire: the kits out there unless they are for fat wheels (which is a good thing to consider doing) have rims way too narrow to put on a decent tire like the 2.40 above, or the 3.0 that same rim is holding onto below. The rim I am using above (and its a custom wheel build) is a Stranger Crux XL and its has a 35mm inside width. You need that, but will probably only get something like 19mm on non-fat wheel kits. BTW the wheel below is different (I have two of these bikes) and is an Alienation Blacksheep which is IIRC a 27mm internal width, and super strong. 27mm is still wide enough to handle a 3.0" tire but its on the narrow side.
You want a fat wheel and fork (solid! Steel!) that will let you put on a 20x4.0 tire which you can then in turn inflate to 20 psi for rock hard street rides, or say 10 psi for dirt roads and sand. That means a 65mm rim, or up to 80mm., and a fat 20" fork that can handle the width. That means a 135mm fork width. The 3.0 tire I show above was wonderfully compliant and still rolled well at 10 psi, which sounds crazy-low but bigger bike tires work like that.
I am using a Bafang G020 hub which is very common, but what is not so common is its a 500w motor rated for a 48v system. Usually what you find is a 36v motor with a 250w or 350w rating. All of them are rated for 45Nm but the lower rated Bafang motors MIGHT have less copper in their windings and in any event are not meant for 48v, which you need instead of 36v. 52v is actually ideal if you can get hold of batteries at that voltage. Also, look to KT controllers as they can be set to slow-start which will also help preserve your forks as well as controllability.
Here are a couple of pics of the 20" front motor wheels I am using. I HIGHLY recommend the Maxxis Minion 20x2.40" tire as one that has a strong casing and can take just about anything you throw at it. I use mine to navigate sand and allow me a mild off-road capability. You'll notice I am using a physically smaller hub motor. That is because its what is called a geared hub. The type of motor the other guys are using is called a Direct Drive motor. They are maintenance free, but they need more power to deliver the same level of torque output. Thats why you will probably see 1000w on them but not get any more than the same 45 Nm of both of them. Geared hubs provide better performance when the going gets tough (i.e. dirt or low rolling hills).
But know that a hub motor is never in its element in dirt or hills. The performance you see in that video is for an awd chair and the reason they can do those things is because all of the wheels are powered and they have distributed traction. You won't be able to come remotely close to that with a single front motor so hopefully you already have the rear wheels powered.
Some things about using a bigger tire: the kits out there unless they are for fat wheels (which is a good thing to consider doing) have rims way too narrow to put on a decent tire like the 2.40 above, or the 3.0 that same rim is holding onto below. The rim I am using above (and its a custom wheel build) is a Stranger Crux XL and its has a 35mm inside width. You need that, but will probably only get something like 19mm on non-fat wheel kits. BTW the wheel below is different (I have two of these bikes) and is an Alienation Blacksheep which is IIRC a 27mm internal width, and super strong. 27mm is still wide enough to handle a 3.0" tire but its on the narrow side.
I am using a Bafang G020 hub which is very common, but what is not so common is its a 500w motor rated for a 48v system. Usually what you find is a 36v motor with a 250w or 350w rating. All of them are rated for 45Nm but the lower rated Bafang motors MIGHT have less copper in their windings and in any event are not meant for 48v, which you need instead of 36v. 52v is actually ideal if you can get hold of batteries at that voltage. Also, look to KT controllers as they can be set to slow-start which will also help preserve your forks as well as controllability.
thanks for getting back to me with all that info @m@Robertson, but i already have a front wheel drive system, im trying to build the rear 2 wheels at the back, so i thought 2 motors meant for the front of a bike would be more suited as a rear one has all that extra stuff for the gears, i was wanting to weld the threaded part of a front wheel motor and cut off the other end, run the wires through the axle and come out the middle to a speed controller for both sides, then ill need to get another speed controller i think to replace the front one as i dont think they will talk to each other, the system you see with the guy on the sand cost £6k thats why im trying to build my own even if it cost £2k, but yes i will need a 48v system as thats what my front one is already so its got to be compatible with that, ill link a picture of a one that someone bought to show you what im after, is the bafang HF550 any good for my application?
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m@Robertson
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Probably its overkill. Go back to what I was saying about the fork surviving. I have worked with the G060 which is the predecessor to the H550 (also sold as the G062). I have done 80Nm G060's on front wheels tied to 35a controllers with a 52v battery and its so powerful you need to slow it down with a KT controller's slow-start setting or it pulls so hard you have safety issues along with worries about the fork holding together long term.
I can tell you from having to find them myself that there are times when front-motor versions of these fat motors is completely impossible. If you have a source, buy it sooner not later because when they go out of supply they can stay that way for a year or more.
I bought one here.
https://electrobikeworld.com/products/750w-bafang-front-hub-motor
As well as the 35a controller they sell. That was before Bafang changed the motor plug to the red one. This seller also sells adapters which is very rare in the aftermarket. Or at least it is around here on this side of the world.
BTW I am a big fan of awd ebikes. You can see a couple of them here that use G060's
https://talesontwowheels.com/2021/03/20/dual-motor-awd-electric-bikes-the-good-and-bad/
im looking at this motor https://www.aliexpress.com/item/1005005338555937.html?spm=a2g0o.cart.0.0.314938daCJFuZT&mp=1 i just need some speed controllers that will work well with it, then i just need to buy the batteries or make a big battery pack
m@Robertson
Well-known member
That is a G060 and you absolutely want the motor with the G9.14 male plug. I use a few of those myself. As far as I am concerned this is the best possible choice. Also I have bought from that seller and I got the motor
KT controllers work great with these motors. They are all I use. You need to buy the 35a controller because what they are calling the 9.14 plug in that advert is unusual for the Bafang motors. Anything smaller (500w motor on down) use a smaller plug and then you have to use a 25a or less controller. Also Electrobikeworld sells an adapter that goes big plug to small plug if you want, but I would buy the 35a controller and a KT-LCD4 display (all the features of the LCD3 or color LCD8 which are the usual defaults, but the LCD4 is cheap and very small so easier to mount and use. Since the LCD4 is a backlit LCD display its perfectly visible in any light or dark condition which you can't get with any other display type. If you don't want to go small then you go with the LCD3 or 8 that you can also see on EBW - and can buy pretty much anywhere.
KT controllers are widely available but its tough to get them with exactly the plugs you want and need. I have always bought from EBW because I know what theirs are set up for. Those controllers btw use a black throttle plug (standard for Sondors bikes) which is very unusual so you need to buy the throttle from them as well if you go thru them.
ok ill look at the kt35 controllers https://electrobikeworld.com/products/35a-controller-rad this one? but i was hoping i could use my twist throttle i already have with the front part of my bike, but judging by what your saying i cant do that, ill have to get a thumb throttle from them to make it work? i also need a reverse do these controllers have that function? thanks
