Buying a 8000w E-bike?

General Discussion about electric bicycles.
kennet_h   100 mW

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Buying a 8000w E-bike?

Post by kennet_h » Apr 27 2018 5:48pm

Hello!

I'm looking to buy a powerful E-bike.

*I want it to be able to go offroad.
*Have 40 mile+ range, riding 40 MPH.
*Have god/stiff suspension(I am 103kg/227lb)
*Can push a button, to make it switch over to 250w power, only assist while i pedal, no assist after 25 KMH.
(This is not a must, but would be a big positive, since it would make it comply with the laws, in Norway)
*40 MPH minimum, but would like it to be able to go 50 MPH and be safe.
Hill climbing, and acceleration, is more important to me, than top speed, as long as it is 40+MPH.

I'm a total noob with this, so it is hard for me to decide what would be the best buy.
I have been looking for something like this

https://www.alibaba.com/product-detail/ ... 1e1ewlMaTv

That is the absolute upper ceiling of what i'm willing to spend, so if i can find something cheaper, that filles my requirements, that would be great!

Any suggestions would be much appreciated! :D

kennet_h   100 mW

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Re: Buying a 8000w E-bike?

Post by kennet_h » Apr 27 2018 6:24pm

I'm also unsure about how big battery i will need.

Anyone who wants to take a guess, on how many W. Would be needed, to push a 103 kg guy 40MPH, on a straight road, with no pedal assist?

markz   100 GW

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Re: Buying a 8000w E-bike?

Post by markz » Apr 27 2018 7:19pm

Dont even bother with that ride off of Alibaba.

Buy yourself a nice regular bicycle, locally.
Then buy yourself a nice em3ev.com triangle bag, and a battery to fit that triangle bag. Then look at the QS direct drive motors, with a Adaptto controller.

pinkbike.com is a good place to start.
local classifieds like Kijiji (Canada) and Craigslist

8000W aint legal, but who knows what the Fuzz is like over there. If you do it right, your bike wont look too out of place. Just dont go around being a complete goof and you wont get pinched.

Adaptto Controller - http://adaptto.envolt.se/
*Get every accessory that goes along with it.
Max-E $745usd + BMS + Coil + Eaton PSU + Balance leads
*While you are at it, they can make your battery for you. Might as well.


QS Motor - https://qsmotor.aliexpress.com/store/109978
Your motor - https://www.aliexpress.com/store/produc ... 3362my7b4e

Battery - www.EM3EV.com (China) or www.ebikes.ca (Canada)
Triangle Bag - www.EM3EV.com

Oh dont forget torque arms, a couple throttles.

kennet_h   100 mW

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Re: Buying a 8000w E-bike?

Post by kennet_h » Apr 27 2018 8:49pm

Thank you for the detailed reply!

I'm a little worried about building it myself, might take a long time, and not end up that good :lol:

Also building a bike with that power, and my weight, on a regular bike, with regular rims/tires, sound a little scary.

But i will definitely take a look at your suggestions, and do some Research :D

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Dauntless   100 GW

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Re: Buying a 8000w E-bike?

Post by Dauntless » Apr 29 2018 2:38am

Maybe you can just pick up one of these and do some upgrades. I just think though an 8000w bike needs to be built of some stern stuff.

https://www.ebay.com/itm/26-350W-Fat-Ti ... 0005.m1851
Any sufficiently advanced technology is INDISTINGUISHABLE FROM MAGIC!
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Compoundbike   100 mW

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Re: Buying a 8000w E-bike?

Post by Compoundbike » Apr 29 2018 4:15am

Just buy a Stealth Bike/Qulbix/Vector bike and save some headache... my opinion.
Also 8000 watt is serious power, my 3kw bike reaches already 40mph+ and im also a 220 pound guy.
Depending the battery; i would go with a 72 V and 40 amp.

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changeissimple   10 W

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Re: Buying a 8000w E-bike?

Post by changeissimple » Apr 29 2018 7:13am

Compoundbike wrote:
Apr 29 2018 4:15am
Just buy a Stealth Bike/Qulbix/Vector bike and save some headache... my opinion.
Also 8000 watt is serious power, my 3kw bike reaches already 40mph+ and im also a 220 pound guy.
Depending the battery; i would go with a 72 V and 40 amp.
I am going to purchase a 3000watt MXUS. Are you running 72v at 40amps to get you to 40mph+???
I was thinking of running a 48v Panasonic PF (high output) battery that i have at 60 amps with a goal of 40mph. I weigh 145lbs. Thoughts??

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MadRhino   100 GW

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Re: Buying a 8000w E-bike?

Post by MadRhino » Apr 29 2018 11:18am

Big hub motors can be fed 20+ Kw bursts in acceleration. So, you might reconsider watt is ‘serious power’.

Two main factors are affecting performance: watts and weight. Those heavy Chinese ebike frames with motorcycle wheels and tires are not so powerful at 8000w.

Nevertheless, fast speed is making it important to build with quality components, and provide conscious maintenance. That is a good reason to build yourself, so you know everything about your bike. If you add shipping and custom fees to a fast Chinese bike, you can build much better for the money.
Make it fool-proof, and I will make a better fool.
Current bikes
Street: https://s20.postimg.org/ewrvugywt/Session_04_2015.jpg
Dirt: https://s20.postimg.org/lbqwr55ml/IMG_0157.jpg

markz   100 GW

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Re: Buying a 8000w E-bike?

Post by markz » Apr 29 2018 2:31pm

You think a generic Alibaba bicycle is quality?

Buy a quality brand name frame and have peace of mind.

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eCue   10 kW

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Re: Buying a 8000w E-bike?

Post by eCue » Apr 29 2018 11:49pm

Might find a worthy ebike in the "for sale" section of this website if not then craigs list or the like. I have seen some bad ass ebikes on craigs list
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miro13car   1 MW

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Re: Buying a 8000w E-bike?

Post by miro13car » Apr 30 2018 8:19am

" just buy Stealth bike..." - just like that USD 10,000 price tag.
I would also stay away from Alibaba purchases, too many bad stories ...

rumme   100 kW

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Re: Buying a 8000w E-bike?

Post by rumme » Apr 30 2018 8:24am

for 40 mph..you sure as hell wont need 8 KW of power....

3-5 KW will easily get you to 40 mph top speed, especially if you use a hub motor mounted in a larger rim/wheel.

I can easily do 45 mph , in a 19 inch rim, with 4-5 KW.....If I were to put the same KW with my hub motor , into a 26 inch rim, top speed will increase.

rumme   100 kW

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Re: Buying a 8000w E-bike?

Post by rumme » Apr 30 2018 8:27am

Compoundbike wrote:
Apr 29 2018 4:15am
Just buy a Stealth Bike/Qulbix/Vector bike and save some headache... my opinion.
Also 8000 watt is serious power, my 3kw bike reaches already 40mph+ and im also a 220 pound guy.
Depending the battery; i would go with a 72 V and 40 amp.
are you truly getting 40-45 mph top speed on flat land with your 220 lb bodyweight using only 3 KW of power { measured with a GPS} ?

If so, is your motor mounted in a 26 inch rim ? For me to get 45 mph top speed, I need to pump about 4500-4900 KW into my rear wheel, and I weigh 210 lbs...but my rear wheel is small 19" rim.

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MadRhino   100 GW

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Re: Buying a 8000w E-bike?

Post by MadRhino » Apr 30 2018 11:19am

rumme wrote:
Apr 30 2018 8:27am
Compoundbike wrote:
Apr 29 2018 4:15am
Just buy a Stealth Bike/Qulbix/Vector bike and save some headache... my opinion.
Also 8000 watt is serious power, my 3kw bike reaches already 40mph+ and im also a 220 pound guy.
Depending the battery; i would go with a 72 V and 40 amp.
are you truly getting 40-45 mph top speed on flat land with your 220 lb bodyweight using only 3 KW of power { measured with a GPS} ?

If so, is your motor mounted in a 26 inch rim ? For me to get 45 mph top speed, I need to pump about 4500-4900 KW into my rear wheel, and I weigh 210 lbs...but my rear wheel is small 19" rim.
Weight should include bike’s weight. Riding weight vs watts is your first measure of power.

Then comes wheel size. If your 19’’ is motorcycle rim, it is about 25’’ OD wheel. It is smaller than a 26’’ bicycle wheel but with higher inertia due to weight. A 24’’ bicycle wheel would be similar in size, but giving better performance with lesser Amp draw.

Next is wind drag, that can be very different between two riders and different bikes.

Many other factors are making effective power differences, to a lesser value. Even riding the same bike, two riders are unlikely to have the same efficiency.
Make it fool-proof, and I will make a better fool.
Current bikes
Street: https://s20.postimg.org/ewrvugywt/Session_04_2015.jpg
Dirt: https://s20.postimg.org/lbqwr55ml/IMG_0157.jpg

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Compoundbike   100 mW

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Re: Buying a 8000w E-bike?

Post by Compoundbike » Apr 30 2018 2:10pm

rumme wrote:
Apr 30 2018 8:27am
Compoundbike wrote:
Apr 29 2018 4:15am
Just buy a Stealth Bike/Qulbix/Vector bike and save some headache... my opinion.
Also 8000 watt is serious power, my 3kw bike reaches already 40mph+ and im also a 220 pound guy.
Depending the battery; i would go with a 72 V and 40 amp.
are you truly getting 40-45 mph top speed on flat land with your 220 lb bodyweight using only 3 KW of power { measured with a GPS} ?

If so, is your motor mounted in a 26 inch rim ? For me to get 45 mph top speed, I need to pump about 4500-4900 KW into my rear wheel, and I weigh 210 lbs...but my rear wheel is small 19" rim.
Im not sure how much the "Burst" Watt was, but my QS205 V2 on a Quilbix Q76R saw real 45 mph on a Forest gravel Road. Usually i run 3kW..
MadRhino wrote:
Apr 29 2018 11:18am

Two main factors are affecting performance: watts and weight. Those heavy Chinese ebike frames with motorcycle wheels and tires are not so powerful at 8000w.

on that picture the bike has a QS273 which is already very powerful.. but im not sure if the "chinese" batteries will support that.

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MadRhino   100 GW

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Re: Buying a 8000w E-bike?

Post by MadRhino » Apr 30 2018 8:46pm

Compoundbike wrote:
Apr 30 2018 2:10pm

on that picture the bike has a QS273 which is already very powerful.. but im not sure if the "chinese" batteries will support that.
It is unlikely that enough batteries are included to give full advantage of this motor. It is also unlikely that most components are up to the task. Then, if it is fed only 8000w, a 273 is a boat anchor.
Make it fool-proof, and I will make a better fool.
Current bikes
Street: https://s20.postimg.org/ewrvugywt/Session_04_2015.jpg
Dirt: https://s20.postimg.org/lbqwr55ml/IMG_0157.jpg

MiddleBrook723   1 µW

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Re: Buying a 8000w E-bike?

Post by MiddleBrook723 » Apr 30 2018 11:22pm

markz wrote:
Apr 29 2018 2:31pm
You think a generic Alibaba bicycle is quality?

Buy a quality brand name frame and have peace of mind.
True, I would not trust an Alibaba build. :P

kennet_h   100 mW

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Re: Buying a 8000w E-bike?

Post by kennet_h » May 01 2018 2:25am

So what would be the best 8kw motor to get? The QS 273?http://www.cnqsmotor.com/en/article_rea ... r/264.html

And could anyone recommend a good frame, that will fit a 72V 40ah battery?

I'm a little hesitant to build something myself.

Do the engines die often, or are there a good life expectancy?

Even if i decide to build it myself, it will end up looking pretty much like the one i linked to, in the first post.

I do not trust bicycle rims/tires, with my weight and 60 MPH.

kennet_h   100 mW

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Re: Buying a 8000w E-bike?

Post by kennet_h » May 02 2018 9:21pm

If i want to accelerate fast, and cruise at 80KMH/50MPH.
And have long life expectancy of the motor, would this be a good alternative?

http://www.cnqsmotor.com/en/article_rea ... r/260.html

Any other motor that would be better suited?

recommendations for a controller would also be appreciated.

The Adaptto controller recommended earlier, looks really good, but if it could be done for a better price, with good life expectancy, that would be great!

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MadRhino   100 GW

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Re: Buying a 8000w E-bike?

Post by MadRhino » May 02 2018 9:53pm

Wheel size?
Total riding weight expected (bike and rider)?
Hills?

IMO, the 273 is overkill for your requirements.
Unless you ride heavy and/or very hilly terrain, you’d be fine with the QS205v3 H50. Cheap controller for the performance that you seek, is to buy the controller recommended by QS for this motor. That would be a Kelly, and they sell it for a good price.
Make it fool-proof, and I will make a better fool.
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Street: https://s20.postimg.org/ewrvugywt/Session_04_2015.jpg
Dirt: https://s20.postimg.org/lbqwr55ml/IMG_0157.jpg

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Chalo   100 GW

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Re: Buying a 8000w E-bike?

Post by Chalo » May 02 2018 10:21pm

What happens after the cops decide you're riding an illegal unlicensed motorcycle?
This is to express my gratitude to Justin of Grin Technologies for his extraordinary measures to save this forum for the benefit of all.

kennet_h   100 mW

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Re: Buying a 8000w E-bike?

Post by kennet_h » May 02 2018 10:45pm

I think i would use 19" rims.

Total riding weight, about 170kg.

There is some steep hills, where i live.
I would ride it as hard as i could, and still make it last for a while. (Don't know how hard that would be?)

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Chalo   100 GW

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Re: Buying a 8000w E-bike?

Post by Chalo » May 02 2018 11:21pm

No really, do you have a plan for when the police decide to crack down on an obvious violator? Or are you going to trust that they take it easy on you?
This is to express my gratitude to Justin of Grin Technologies for his extraordinary measures to save this forum for the benefit of all.

kennet_h   100 mW

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Re: Buying a 8000w E-bike?

Post by kennet_h » May 02 2018 11:29pm

Depends on my mood i guess 8)
Overpowered E-bikes is not prioritised by the norwegian police at the moment.

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MadRhino   100 GW

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Re: Buying a 8000w E-bike?

Post by MadRhino » May 02 2018 11:59pm

Yep. Norway is cool with fast ebikes.

Your riding weight, and climbing, with motorcycle wheels and lots of batteries to do long rides, are making the 273 a good choice for heat dissipation.
Make it fool-proof, and I will make a better fool.
Current bikes
Street: https://s20.postimg.org/ewrvugywt/Session_04_2015.jpg
Dirt: https://s20.postimg.org/lbqwr55ml/IMG_0157.jpg

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