High power ebike frame

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John1deere   100 mW

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High power ebike frame

Post by John1deere » Aug 22 2018 11:32pm

Looking for some help here. Going for a winter project and largest drop out i found seems to be 150-155mm. When i look at qs motor like the 273 it seems like its a 200mm motor.

So my question is this. Is there any ebike frame kit available with a 200mm drop out? Or is there any other kind of motor that can handle 20kw at 150mm?

If theres a post of someone making something similar id be glad if you could link it here.

Plan is 30s so 128v and a motocross ish kind of ebike. Wont do any crazy jump but need to be strong enough for rough trail riding.

Thanks for you guys input!

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Chalo   100 GW

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Re: High power ebike frame

Post by Chalo » Aug 23 2018 2:18am

QS273 is rated 4kW, not 20kW. Max continuous current rating is 55A, which is just under 4kW electrical at 72V. Peak current rating is 110A, which is a little less than 8kW electrical but surely throws away much of that power as waste heat.

There's no way in the world I'd consider stuffing 20kW through a motor with only that rinkydink axle to restrain the torque.

Would you buy an 80hp economy car with the intention of getting it to produce 400hp? The results would be predictable, but actually yielding 400hp would not be likely.
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Re: High power ebike frame

Post by Tony01 » Aug 23 2018 2:51am

Qs273 is a motorcycle motor. you can easily modify a motorcycle frame. 200mm is a standard swingarm size. You’ll just have to figure out the torque arms.
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Re: High power ebike frame

Post by John in CR » Aug 23 2018 5:54am

For "rough trail riding" you want a mid-drive rig (motor out of the wheel). About the only one I know who does serious offroad with a hubbie is MadRhino, but he's a veteran downhiller who doesn't mind the maintenance to keep it tuned and in good working order and is willing to open the pocketbook for premium parts to keep the weight reasonable. The big 273 is far heavier than the motors he uses. Once you go to motorcycle parts the weight skyrockets enough that hubbies don't cut it for off-road.

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Re: High power ebike frame

Post by John1deere » Aug 23 2018 8:49am

Chalo wrote:
Aug 23 2018 2:18am
QS273 is rated 4kW, not 20kW. Max continuous current rating is 55A, which is just under 4kW electrical at 72V. Peak current rating is 110A, which is a little less than 8kW electrical but surely throws away much of that power as waste heat.

There's no way in the world I'd consider stuffing 20kW through a motor with only that rinkydink axle to restrain the torque.

Would you buy an 80hp economy car with the intention of getting it to produce 400hp? The results would be predictable, but actually yielding 400hp would not be likely.
According to this page its a 8000 watt hub. At 100v and 200 amp peak like they say thats 20 kw 🤔
http://www.cnqsmotor.com/en/article_read/QSMotor High Speed powered 120kph 8000W 273 50H V3 electric wheel hub motor with Conversion Kits/842.html

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Re: High power ebike frame

Post by John1deere » Aug 23 2018 9:34am

Tony01 wrote:
Aug 23 2018 2:51am
Qs273 is a motorcycle motor. you can easily modify a motorcycle frame. 200mm is a standard swingarm size. You’ll just have to figure out the torque arms.
I would do that but then i need to license and insure it which means i cant ride it on the road to get at my trails. So yeah not interested in that route

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Chalo   100 GW

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Re: High power ebike frame

Post by Chalo » Aug 23 2018 10:37am

John1deere wrote:
Aug 23 2018 8:49am
Chalo wrote:
Aug 23 2018 2:18am
QS273 is rated 4kW, not 20kW. Max continuous current rating is 55A, which is just under 4kW electrical at 72V. Peak current rating is 110A, which is a little less than 8kW electrical but surely throws away much of that power as waste heat.
According to this page its a 8000 watt hub. At 100v and 200 amp peak like they say thats 20 kw 🤔
http://www.cnqsmotor.com/en/article_read/QSMotor High Speed powered 120kph 8000W 273 50H V3 electric wheel hub motor with Conversion Kits/842.html
Your link doesn't work for me. But I understand now that you are looking at a different motor than the QS273 whose specs I looked up.

The one I found specs for has a much narrower axle, for example.

You understand that a 20kW bicycle, or a 4kW bicycle, is in fact just as illegal as a motorcycle with no registration or insurance, right? There's no difference in terms of the law.
This is to express my gratitude to Justin of Grin Technologies for his extraordinary measures to save this forum for the benefit of all.

John1deere   100 mW

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Re: High power ebike frame

Post by John1deere » Aug 23 2018 10:41am

Chalo wrote:
Aug 23 2018 10:37am
John1deere wrote:
Aug 23 2018 8:49am
Chalo wrote:
Aug 23 2018 2:18am
QS273 is rated 4kW, not 20kW. Max continuous current rating is 55A, which is just under 4kW electrical at 72V. Peak current rating is 110A, which is a little less than 8kW electrical but surely throws away much of that power as waste heat.
According to this page its a 8000 watt hub. At 100v and 200 amp peak like they say thats 20 kw 🤔
http://www.cnqsmotor.com/en/article_read/QSMotor High Speed powered 120kph 8000W 273 50H V3 electric wheel hub motor with Conversion Kits/842.html
Your link doesn't work for me. But I understand now that you are looking at a different motor than the QS273 whose specs I looked up.

The one I found specs for has a much narrower axle, for example.

You understand that a 20kW bicycle, or a 4kW bicycle, is in fact just as illegal as a motorcycle with no registration or insurance, right? There's no difference in terms of the law.
Not everyone lives in the usa 🙄

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Chalo   100 GW

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Re: High power ebike frame

Post by Chalo » Aug 23 2018 11:10am

John1deere wrote:
Aug 23 2018 10:41am
You understand that a 20kW bicycle, or a 4kW bicycle, is in fact just as illegal as a motorcycle with no registration or insurance, right? There's no difference in terms of the law.
Not everyone lives in the usa 🙄
I thought Canadia had a 500W limit for e-bikes?

The relevant Wikipedia article says this:
Eight provinces of Canada allow electric power assisted bicycles. In all eight provinces, e-bikes are limited to 500 W output, and cannot travel faster than 32 km/h (20 mph) on motor power alone on level ground.
I think you're just as illegal on the road with an unregistered, uninsured motorcycle that has pedals as you are with one than doesn't. If so, your plan will only work until it doesn't.
This is to express my gratitude to Justin of Grin Technologies for his extraordinary measures to save this forum for the benefit of all.

John1deere   100 mW

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Re: High power ebike frame

Post by John1deere » Aug 23 2018 11:19am

Chalo wrote:
Aug 23 2018 11:10am
John1deere wrote:
Aug 23 2018 10:41am
You understand that a 20kW bicycle, or a 4kW bicycle, is in fact just as illegal as a motorcycle with no registration or insurance, right? There's no difference in terms of the law.
Not everyone lives in the usa 🙄
I thought Canadia had a 500W limit for e-bikes?

The relevant Wikipedia article says this:
Eight provinces of Canada allow electric power assisted bicycles. In all eight provinces, e-bikes are limited to 500 W output, and cannot travel faster than 32 km/h (20 mph) on motor power alone on level ground.
I think you're just as illegal on the road with an unregistered, uninsured motorcycle that has pedals as you are with one than doesn't. If so, your plan will only work until it doesn't.
Except that i dont live in canada. My vpn does tho. So how about stop being a smart ass and try to tell me what i can or cant do?

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Chalo   100 GW

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Re: High power ebike frame

Post by Chalo » Aug 23 2018 11:24am

Why did you fill in your location field with a place you aren't in? You can leave it blank, or put in the correct location. Then the information you get could be more relevant.
This is to express my gratitude to Justin of Grin Technologies for his extraordinary measures to save this forum for the benefit of all.

John1deere   100 mW

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Re: High power ebike frame

Post by John1deere » Aug 23 2018 11:25am

Chalo wrote:
Aug 23 2018 11:24am
Why did you fill in your location field with a place you aren't in? You can leave it blank, or put in the correct location. Then the information you get could be more relevant.
Or you could just not answer questions i never asked and not be a smart ass. That works too.

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Chalo   100 GW

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Re: High power ebike frame

Post by Chalo » Aug 23 2018 11:27am

John1deere wrote:
Aug 23 2018 11:25am
Chalo wrote:
Aug 23 2018 11:24am
Why did you fill in your location field with a place you aren't in? You can leave it blank, or put in the correct location. Then the information you get could be more relevant.
Or you could just not answer questions i never asked and not be a smart ass. That works too.
I was addressing a point you brought up yourself.

Do you think your manner will win you lots of friends here?
This is to express my gratitude to Justin of Grin Technologies for his extraordinary measures to save this forum for the benefit of all.

John1deere   100 mW

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Re: High power ebike frame

Post by John1deere » Aug 23 2018 11:31am

Chalo wrote:
Aug 23 2018 11:27am
John1deere wrote:
Aug 23 2018 11:25am
Chalo wrote:
Aug 23 2018 11:24am
Why did you fill in your location field with a place you aren't in? You can leave it blank, or put in the correct location. Then the information you get could be more relevant.
Or you could just not answer questions i never asked and not be a smart ass. That works too.
I was addressing a point you brought up yourself.

Do you think your manner will win you lots of friends here?
When did i talk about a bicycle being legal or not on the road? All i said is if i use a motorcycle frame i will have to register it 🤔. Then you came along saying my bicycle wont be legal on the road assuming i live somewhere i do not(usa and then canada). As long as theres working pedals on my bicycle its legal and thats it.

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Re: High power ebike frame

Post by 999zip999 » Aug 23 2018 11:22pm

Thick skin thick skin and don't take it personal some of these people just aren't answering your question but they're answering a question what they believe is true so it's not a personal thing

John1deere   100 mW

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Re: High power ebike frame

Post by John1deere » Aug 23 2018 11:25pm

999zip999 wrote:
Aug 23 2018 11:22pm
Thick skin thick skin and don't take it personal some of these people just aren't answering your question but they're answering a question what they believe is true so it's not a personal thing
A question that never been asked tho 😂

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Re: High power ebike frame

Post by 999zip999 » Aug 23 2018 11:44pm

I think 5000 Watts is the beginning of enjoyment. Go for it. As for an ebike it's a emotor cycle. Which is good. It's about the quality of the battery's er you're going to use if you wanted anything as life out of the battery or ride.
Last edited by 999zip999 on Aug 23 2018 11:48pm, edited 1 time in total.

John1deere   100 mW

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Re: High power ebike frame

Post by John1deere » Aug 23 2018 11:48pm

999zip999 wrote:
Aug 23 2018 11:44pm
I think 5000 Watts is the beginning of enjoyment. Go for it.
Yeah i got a 3000 watt ebike atm and coming from motocross its lacking lol. Really fun to zip around and commute but off road its meh.

I just wonder where do the "ripping" starts

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Re: High power ebike frame

Post by 999zip999 » Aug 23 2018 11:54pm

Like I say 72 volt and a battery that can push 100 amps get a temp gauge on that motor as not to melt as I have melted many Cytalyte Muxus 9c and bmc motors. Same batteries. But heavy. Looking for new source for high power battery. High capacity go far Low Watts. What battery combo are you comfortable with running ?

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Re: High power ebike frame

Post by John1deere » Aug 24 2018 12:04am

999zip999 wrote:
Aug 23 2018 11:54pm
Like I say 72 volt and a battery that can push 100 amps get a temp gauge on that motor as not to melt as I have melted many Cytalyte Muxus 9c and bmc motors. Same batteries. But heavy. Looking for new source for high power battery. High capacity go far Low Watts. What battery combo are you comfortable with running ?
Right now im at 72v 40 amps on a crystalyte 3540
20s10p lg f1l
Got 280 samsung 30q waiting and will most likely buy 400 or so lg hg2 in a few days.
I was thinking going 30s for the next build

999zip999   100 GW

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Re: High power ebike frame

Post by 999zip999 » Aug 24 2018 10:41am

Oh 24s of A123 20ah .1,135 cycles 5yrs. It's a very good powerful battery but is twice as heavy as it should be. You my be looking at a muxus 3,000 4t in your future.

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Re: High power ebike frame

Post by Tony01 » Aug 26 2018 11:56pm

Qs273 is a BIG motor. It’s going to handle like shit pretty much anywhere except for drag racing. Too much rotational mass too far away from the best place (the middle). For off-road you will want to go with a mid drive. Your best bet for a swingarm is still a dirtbike 200mm swingarm. That takes care of a lot of the rear end fabrication. Fab up the bike however you want. Frame kits sold look like dirt bikes. I’m working on a weld yourself kit that converts a Schwinn cruiser frame to full suspension. Basically laser cut plates that you weld to a sleeved seat tube and bottom bracket, and include swingarm pivot spot and monoshock upper mount. Lmk if you are interested. Mine will have a 205 and I plan to do 95% road. If you are doing light flat trails it will be OK but still way too damn heavy. Remember the 273 weighs around 45lbs JUST FOR THE MOTOR. With a rim, spokes and tire you can assume 65-70lb easily. All of that weight resisting changes in direction. I’d suggest a mid drive using a decent bldc like a motenergy, and a single chain to a dirtbike rear wheel. Whatever you’re thinking, rethink it.

And you’ll have to excuse people like Chalo. There’s a lot of very liberal left leaning environmental types here who cannot or will not answer a question directly and will change the subject entirely to avoid answering... don’t take it personally.
I don't always listen to Alice in Chains.... but when I do, SO DO THE NEIGHBORS :D

John1deere   100 mW

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Re: High power ebike frame

Post by John1deere » Aug 27 2018 10:45am

Tony01 wrote:
Aug 26 2018 11:56pm
Qs273 is a BIG motor. It’s going to handle like shit pretty much anywhere except for drag racing. Too much rotational mass too far away from the best place (the middle). For off-road you will want to go with a mid drive. Your best bet for a swingarm is still a dirtbike 200mm swingarm. That takes care of a lot of the rear end fabrication. Fab up the bike however you want. Frame kits sold look like dirt bikes. I’m working on a weld yourself kit that converts a Schwinn cruiser frame to full suspension. Basically laser cut plates that you weld to a sleeved seat tube and bottom bracket, and include swingarm pivot spot and monoshock upper mount. Lmk if you are interested. Mine will have a 205 and I plan to do 95% road. If you are doing light flat trails it will be OK but still way too damn heavy. Remember the 273 weighs around 45lbs JUST FOR THE MOTOR. With a rim, spokes and tire you can assume 65-70lb easily. All of that weight resisting changes in direction. I’d suggest a mid drive using a decent bldc like a motenergy, and a single chain to a dirtbike rear wheel. Whatever you’re thinking, rethink it.

And you’ll have to excuse people like Chalo. There’s a lot of very liberal left leaning environmental types here who cannot or will not answer a question directly and will change the subject entirely to avoid answering... don’t take it personally.
Id be interested in picture for sure. I taught about going with "fab work" and do a "mid drive" with its own chain not like a bafang or similar but it will involve so much more work that im not sure i wanna go that route 😂. But yes that would def be optimal i just feel a bit too lazy lol. Hell i already have a spare motocross swing arm i just never measured its drop out.

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brumbrum   100 kW

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Re: High power ebike frame

Post by brumbrum » Aug 27 2018 1:57pm

QS273 is the completely wrong motor for your purposes. You do not need 20kw for off-roading. 20kw peak power is just over the top and a waste of battery fuel. The weight of a 273 in a motorbike rim and a mx tyre is going to be like having the Titanics anchor attached to the rear end of a trail bike. what kind of trails are there where you need 70+mph? 50mph is plenty and can be done with a cromotor or qs205. I have a cromotor laced into a 17" moto rim with a 3" mx tyre and it weighs 20kg, which is more than enough to have at the rear end.
My NYX and cromotor build
viewtopic.php?f=6&t=74615
My LMX 161 dirt bike build
viewtopic.php?f=6&t=94074

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brumbrum   100 kW

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Re: High power ebike frame

Post by brumbrum » Aug 27 2018 2:19pm

Mid drive will be more work, but will give you better balanced bike with lots of torque,, but also lots of noise. Hub motors can have lots of torque too, but are silent if paired up with a sinewave controller and will make for an easier build. Hub motor can overheat, but this can be remedied with statorade and a hubsink.
My NYX and cromotor build
viewtopic.php?f=6&t=74615
My LMX 161 dirt bike build
viewtopic.php?f=6&t=94074

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