Help and advice for a 3kw ebike build

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gursi123   100 µW

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Help and advice for a 3kw ebike build

Post by gursi123 » Jan 18 2020 8:07pm

If I am doing something wrong or writing in the wrong forum let me know and I will delete it.
I have built a 2kw ebike using a hub motor kit that came complete with everything and I loved it but sold it as I wanted to make another more powerful build but is proving to be harder than I thougth. Nobody offers a ready to go 3kw hub motor build, or at least feauturing the specs I would like to have.
My perfect build would be:
Top speed: doesn't matter to me, probably will never even ride faster than 35 (maybe once in a long while 40) mph so even if it can't go faster than 35 mph is fine for me.

Range: plenty please, I am a deliveroo rider (food delivery rider) and the more range the better it is.

PAS!!!!: I would like to have a pedal assist function. To get the most range pedal assist is essential and I want a bicycle, not a motorcycle so pas is crucial.

Cassette: I can't really establish my mind to get that single speed hub motor, I really want a cassette at the back, possibly 9 speed (I know is too much considering that a 3kw motor drop out is already wide, 9 speed would make it too wide for normal mountain bikes) but anything including and over 6 speed is fine.

Budget: excluding the frame as I am planning to build it on my voodoo hoodoo that I already have, budget is £1300 max, I know, a tight budget!!

Occasionally want to bring it offroad so would like to have good torque and climbing ability, I don't mind sacrificing speed, as mensioned above.

I was looking at the mxus 3000 4t or 5t, but can't find anyone who offers a cassette option, maybe I didn't look hard enough but if there is any other motor out there that can support a cassette list it below I will have a look.
I know not many controllers support pedal assist and I couldn't fine any that does support it.
I would like to be able to limit the power output of the controller as I won't need 3kw all the time lets say limit it to 1.5kw when on the road so do I need a programmable controller? Sabvton perhaps even tho it is expensive and my budget is limited?

Now a few questions: difference between a 3t and a 5t is speed and torque, 5t offers way more torque and 3t spins faster at the same voltage compared to the 3t, let's say we run them both side to side on the same flat road at 20 mph with the same exact bike, controller, rider weight ecc.. (presuming that the 3t top speed on the wheel I got is 50mph and the 5t top speed is 40 mph) is the power consumption gonna be the same? What if we run them in the same condition but at 35 mph? Will the 3t motor consume less power than the 5t as the 5t is about to hit top speed? Now uphills, is the 5t just more efficient in climbing hills or it has more climbing capabilities? What I mean by this question is, is the 5t motor gonna consume less power to run up the same hill compared to the 3t motor if they are both travelling at the same speed, lets say 15% incline hill at 20mph, which motor is consuming more power? And by what % roughly and which one is getting hotter and bow faster is it getting hotter?

Now onto the controller: what if for my 3kw build I get a controller than can handle 4kw continuous, do I risk less on blowing it or the chances of blowing it are the same?

Final question is about battery: low voltage high amps or high voltage low amps? More specifically, if you were in my situation and wanted to build something like I want to, would you go for a 60v 25ah battery pack or a 72v 21ah pack? Both have the capacity of 1500 wh, that means both will give me the same range, in theory, but in practical, will they give me the same range?

I have considered the bbshd too but is well expensive, doesn't really fit in my budget (or it does? I might not have looked into it porperly?)

If you already know what I am looking for and have a ready list of the parts I need, list them, that would be perfect! Or if you can give a bit of advice too or something I need to know while building this, I am listening to that too.

Thanks for your replies, let's see what I can build :)

markz   100 GW

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Re: Help and advice for a 3kw ebike build

Post by markz » Jan 18 2020 11:26pm

Your mxus 3000w idea is right, but no need to worry about cassette option, just get the normal hub with a freewheel on it. While ebiking we hardly use any gears at all, some of use no gears at all, some will use one gear fixed gear. A 1x7 drive train is plenty for ebiking, while hardly using more then 5 of those gears in total.

Normal website presence - https://www.mxus-motor.com/
Alibaba presence - https://ebikemotor.en.alibaba.com/?spm= ... 7dc1Z04yvB

Greentime controllers - https://evfittinggreentime.aliexpress.c ... 248317.1_0

Pick up a few spare throttles, a torque arm set

goatman   10 kW

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Re: Help and advice for a 3kw ebike build

Post by goatman » Jan 19 2020 12:13am

$1300 budget, id spend most of it on a good battery, high amp like 15 amp minimum. a 21700 Samsung 40t/35amp 4000mah or 18650 Samsung 30q 15amp/3000 mah.

youre in the uk so a waterproof controller like the phaserunner, I have 2 phaserunners that they sold me at a little discount because they had a cosmetic defect. they work great and flash codes at you if somethings wrong so you know, like my hall sensor is fried but you wouldn't know it because its a high quality controller that runs sensored or sensorless and really good regen

mxusv3 has a 4t and it gets more range than a crystallite 3540.

id go higher volts than amps, 4o amps is a lot and you don't need such heavy gauge wiring. amps create heat and amps kill more things than volts do.

grin technologies sell kits and you can use their motor simulator.

like you I don't want a motorbike but I want power and range, you pretty much have to have a good battery to start with. you don't have the budget to get what youre asking for.

theres a guy on youtube Andy Kirby, hes in the uk and he has an online store. id start there

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dogman dan   100 GW

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Re: Help and advice for a 3kw ebike build

Post by dogman dan » Jan 19 2020 6:53am

Well, here I go again.. Get a gas motorcycle, or scooter.

You want a light motorcycle powered vehicle, and extreme range. The cost for that, in battery alone, is going to be huge. And then the bike is so loaded down with battery, it will wobble like shit when you get above 30 mph.

Not saying it can't be done,,, it can.. But not easy. You are gong to have to give on a few things. Like cassette.

You can get 9 speed screw on freewheels, but really,,,, come on,,, 7 gears in back is plenty. Get more gear range with triple front gears.

Put it on a very sturdy steel frame bike, that you can modify at will, like making the rear wider, so it fits the more powerful motors, with 7 gears. Then you gotta carry a crapton of batteries. Here is how I solved that problem, by taking only the headset and a small bit of the frame on a steel bike, and welding battery trays into the frame. This bike could carry 2 48v 20 amp hour batteries in the frame, and two more in the saddle bags if needed. I built this bike for 100 mile range without a recharge, at 15 mph.

See the mixte thread link in my signature for the full build details.
Finished cargo mixte..jpg
Finished cargo mixte..jpg (133.85 KiB) Viewed 1212 times

gursi123   100 µW

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Re: Help and advice for a 3kw ebike build

Post by gursi123 » Jan 19 2020 7:27am

markz wrote:
Jan 18 2020 11:26pm
Your mxus 3000w idea is right, but no need to worry about cassette option, just get the normal hub with a freewheel on it. While ebiking we hardly use any gears at all, some of use no gears at all, some will use one gear fixed gear. A 1x7 drive train is plenty for ebiking, while hardly using more then 5 of those gears in total.

Normal website presence - https://www.mxus-motor.com/
Alibaba presence - https://ebikemotor.en.alibaba.com/?spm= ... 7dc1Z04yvB

Greentime controllers - https://evfittinggreentime.aliexpress.c ... 248317.1_0

Pick up a few spare throttles, a torque arm set
Well thanks, that's one less worry, I see everywhere saying "available freewheel" so I am sorted for that now. Cherrs

gursi123   100 µW

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Re: Help and advice for a 3kw ebike build

Post by gursi123 » Jan 19 2020 8:14am

goatman wrote:
Jan 19 2020 12:13am
$1300 budget, id spend most of it on a good battery, high amp like 15 amp minimum. a 21700 Samsung 40t/35amp 4000mah or 18650 Samsung 30q 15amp/3000 mah.

youre in the uk so a waterproof controller like the phaserunner, I have 2 phaserunners that they sold me at a little discount because they had a cosmetic defect. they work great and flash codes at you if somethings wrong so you know, like my hall sensor is fried but you wouldn't know it because its a high quality controller that runs sensored or sensorless and really good regen

mxusv3 has a 4t and it gets more range than a crystallite 3540.

id go higher volts than amps, 4o amps is a lot and you don't need such heavy gauge wiring. amps create heat and amps kill more things than volts do.

grin technologies sell kits and you can use their motor simulator.

like you I don't want a motorbike but I want power and range, you pretty much have to have a good battery to start with. you don't have the budget to get what youre asking for.

theres a guy on youtube Andy Kirby, hes in the uk and he has an online store. id start there
It's 1300 gbp which is close to 1700 usd but is still a tight budget.. higher voltage over current, roger that! Kirby bike store most powerful kit is at 1.5kw, my last ebike was 2kw so don't really fancy going down in power ;) by the way the battery I had was a 52v 17.5ah downtube battery and surprisingly it use to last me for about 60 max 70 miles (thats over 100km!!!) on pas setting 1 (250-300 watts) with occasional bursts of 1800-2000 watts using throttle, but still, 60 miles is crazyy!
What do you think about this?

https://www.elecycles.com/mxus-3000w-mo ... motor.html

I know elecycles has a decent reputation and it offers me the option of choosing between the different windings ( I ll go with 4t or 5t) and it has a 26" rim build, perfect for me. It also supports thread freewheel so I can mount the 6/7 speed freewheel, everything I need is in this, right? Or there is a catch somewhere?
Phaserunner controller itself is about £300 😳 I hope that is at least including any display, is it? Also, can you use pedal assist with the phaserunner? And is it hard to program? Just read about an idiot who after hours of programming, reversed the polarities and fried the controller, was he really really stupid or is it a common mistake? Phaserunner can be programmed using your phone on the go too right? Phaserunner works only with cycle analyst or I can hook it up with a display too? As Id like to have the option where I can choose the power mode with just a click or two.
I had a look on grin technology but couldnt find any 3kw set up, did I not look properly?

If the elecycle motor is fine it will be around £300 inlcuding shipping+300 for the phaserunner and I am sitto6ng at £600, would have about £700 (about 900$) left for a battery pack, doable?

This ebike industry is so addictive damn! Will be my third build and cant stop asking for more power and better set ups ahahah

gursi123   100 µW

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Re: Help and advice for a 3kw ebike build

Post by gursi123 » Jan 19 2020 8:16am

dogman dan wrote:
Jan 19 2020 6:53am
Well, here I go again.. Get a gas motorcycle, or scooter.

You want a light motorcycle powered vehicle, and extreme range. The cost for that, in battery alone, is going to be huge. And then the bike is so loaded down with battery, it will wobble like shit when you get above 30 mph.

Not saying it can't be done,,, it can.. But not easy. You are gong to have to give on a few things. Like cassette.

You can get 9 speed screw on freewheels, but really,,,, come on,,, 7 gears in back is plenty. Get more gear range with triple front gears.

Put it on a very sturdy steel frame bike, that you can modify at will, like making the rear wider, so it fits the more powerful motors, with 7 gears. Then you gotta carry a crapton of batteries. Here is how I solved that problem, by taking only the headset and a small bit of the frame on a steel bike, and welding battery trays into the frame. This bike could carry 2 48v 20 amp hour batteries in the frame, and two more in the saddle bags if needed. I built this bike for 100 mile range without a recharge, at 15 mph.

See the mixte thread link in my signature for the full build details. Finished cargo mixte..jpg
Yeah 9 speed is just stupid, only reason I mension that is because that way I dont have to replace the shifter and deraileur on my current bike as it has 9 gears...

goatman   10 kW

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Re: Help and advice for a 3kw ebike build

Post by goatman » Jan 19 2020 6:01pm

yes the phaserunner has a phone app, its not on the fly adjustments and its not Bluetooth. you stop plug the phone in make some changes and go again but grin has the CA3 display for doing other adjustments. you can setup the phaserunner for max performance and use the CA3 to do all the limits and settings including pas. the xt60 battery connector is marked +pos and -neg but someone could think the -neg is a +pos because there is a plastic seam line that turns the -neg into looking like a +plus. that's a newbie thing that can happen. the chamfered edge is neg the flat edge is pos. its not the phaserunners fault things went POOF.

gursi123   100 µW

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Re: Help and advice for a 3kw ebike build

Post by gursi123 » Jan 19 2020 7:36pm

goatman wrote:
Jan 19 2020 6:01pm
yes the phaserunner has a phone app, its not on the fly adjustments and its not Bluetooth. you stop plug the phone in make some changes and go again but grin has the CA3 display for doing other adjustments. you can setup the phaserunner for max performance and use the CA3 to do all the limits and settings including pas. the xt60 battery connector is marked +pos and -neg but someone could think the -neg is a +pos because there is a plastic seam line that turns the -neg into looking like a +plus. that's a newbie thing that can happen. the chamfered edge is neg the flat edge is pos. its not the phaserunners fault things went POOF.
Brilliant, do you know anything about the sabvton or have experience with that controller? It is cheaper than the phaserunner so it is to be considered. Couldn't find any discussion that directly compares the sabvton and the phaserunner.

markz   100 GW

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Re: Help and advice for a 3kw ebike build

Post by markz » Jan 19 2020 10:07pm

I heard/read here on ES that them sabatovs (spelling error?!?!?) take a learning curve on the programming side. Might be a CANBUS thing, might not even have CANBUS, cant remember, easy to search here on ES.

Bicycles are not meant to go 50mph, or 40mph. Imagine hitting a pot hole at those speeds. You might not crash as quick if you laced up motorcycle/moped rims. HolmesHobby used to have rims and spokes but I think he stopped selling. Treatland TV has various rims in narrower sizes., 17" mc rim = 20" bicycle rim and 19" mc rim = 24" bicycle rim, 20" mc rim is very rare but could equate to 26" bicycle rim, 21" is common, I dunno what that would equate to on bicycle, maybe 27 or 28" on a hub motor, less torque/slower to get up to speed, more speed for larger dia rim.

has the 3kw motors from mxus https://www.ebikes.ca/tools/simulator.html
Dont forget the trip simulator - https://www.ebikes.ca/tools/trip-simulator.html

goatman   10 kW

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Re: Help and advice for a 3kw ebike build

Post by goatman » Jan 19 2020 11:18pm

gursi123 wrote:
Jan 19 2020 7:36pm
goatman wrote:
Jan 19 2020 6:01pm
yes the phaserunner has a phone app, its not on the fly adjustments and its not Bluetooth. you stop plug the phone in make some changes and go again but grin has the CA3 display for doing other adjustments. you can setup the phaserunner for max performance and use the CA3 to do all the limits and settings including pas. the xt60 battery connector is marked +pos and -neg but someone could think the -neg is a +pos because there is a plastic seam line that turns the -neg into looking like a +plus. that's a newbie thing that can happen. the chamfered edge is neg the flat edge is pos. its not the phaserunners fault things went POOF.
Brilliant, do you know anything about the sabvton or have experience with that controller? It is cheaper than the phaserunner so it is to be considered. Couldn't find any discussion that directly compares the sabvton and the phaserunner.
youtube, vortecks, he wrote the translation or code or made the app for it, im not sure if it was for the sabvoton or I might be confusing the controller with the bms but check out what hes doing because he actually started something like endless sphere, hes another uk based guy. he documents all of his builds and where to get what

gursi123   100 µW

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Re: Help and advice for a 3kw ebike build

Post by gursi123 » Jan 20 2020 5:09pm

markz wrote:
Jan 19 2020 10:07pm
I heard/read here on ES that them sabatovs (spelling error?!?!?) take a learning curve on the programming side. Might be a CANBUS thing, might not even have CANBUS, cant remember, easy to search here on ES.

Bicycles are not meant to go 50mph, or 40mph. Imagine hitting a pot hole at those speeds. You might not crash as quick if you laced up motorcycle/moped rims. HolmesHobby used to have rims and spokes but I think he stopped selling. Treatland TV has various rims in narrower sizes., 17" mc rim = 20" bicycle rim and 19" mc rim = 24" bicycle rim, 20" mc rim is very rare but could equate to 26" bicycle rim, 21" is common, I dunno what that would equate to on bicycle, maybe 27 or 28" on a hub motor, less torque/slower to get up to speed, more speed for larger dia rim.

has the 3kw motors from mxus https://www.ebikes.ca/tools/simulator.html
Dont forget the trip simulator - https://www.ebikes.ca/tools/trip-simulator.html
I am 19 and even tho I love thrill probably will never attempt hitting 40+, let alone 50 mph on a bicycle, thus I am more towards torque than top speed. I want to live a little longer ahaha. Now that's some useful information, I really apretiate you for telling me that 20" mc rim is equal to a 26" bicycle rim, just researched it and it is completely true damn now I can get a mc rim instead of those wealer bicycle rims, you might have saved me and accident or two lol. However still one question, isn't the mc rim too wide for a bicycle? I just measured the widthness near the tyre on my bicycle and it just a hair over 8cm (3 inches)
I am still waiting for someone to review me this please:
https://www.elecycles.com/mxus-3000w-mo ... motor.html
Thank you!

markz   100 GW

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Re: Help and advice for a 3kw ebike build

Post by markz » Jan 20 2020 8:14pm

Yeah but there is a down side to moped/motorcycle rims/tires/tubes, they are a lot heavier then bicycle stuff.

goatman   10 kW

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Re: Help and advice for a 3kw ebike build

Post by goatman » Jan 20 2020 11:32pm

19 inch mc rim, if you have 3 inches youre fine, you don't want more than 3 inches. the mass is too much to spin.

heres the problem, you need a fat tire bike to fit a 7speed cassette/freewheel. with a mxus v3 and I don't know if it would fit.
to spin that tire you need serious amps, bigger connectors, bigger wires, BIGGER battery, good torque arms, serious brakes. serious money.
I mentioned before, vortecks, his videos on the the v2 or v3 build have all his parts listed and links to the parts. like rims,tires,spokes etc.

im not a mid drive guy but that might be a better option for you. ive seen those guys cruising around at highspeeds with 4.0 tires on bicycle rims. the bikes are light. your build list is atleast 100lb plus bicycle.

im running a crystallite 3540 at 2400 watts with a phaserunner, it has a 7spd freewheel laced to a 24x3.0 tire. its 26inches od/ same as a 26 tire but the fat tire adds suspension. the bike hauls ass for a bike. the 3540 and v3 mxus are pretty much the same motor performance at the volts and amps im running. 17s4p/80amp battery running at 40 amps and bike weighs 70lbs.

check out the Norco atomic in the build thread, its a mid drive or the sinister r9 that's a v3 build with mc rims

gursi123   100 µW

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Re: Help and advice for a 3kw ebike build

Post by gursi123 » Jan 21 2020 6:41am

goatman wrote:
Jan 20 2020 11:32pm
19 inch mc rim, if you have 3 inches youre fine, you don't want more than 3 inches. the mass is too much to spin.

heres the problem, you need a fat tire bike to fit a 7speed cassette/freewheel. with a mxus v3 and I don't know if it would fit.
to spin that tire you need serious amps, bigger connectors, bigger wires, BIGGER battery, good torque arms, serious brakes. serious money.
I mentioned before, vortecks, his videos on the the v2 or v3 build have all his parts listed and links to the parts. like rims,tires,spokes etc.

im not a mid drive guy but that might be a better option for you. ive seen those guys cruising around at highspeeds with 4.0 tires on bicycle rims. the bikes are light. your build list is atleast 100lb plus bicycle.

im running a crystallite 3540 at 2400 watts with a phaserunner, it has a 7spd freewheel laced to a 24x3.0 tire. its 26inches od/ same as a 26 tire but the fat tire adds suspension. the bike hauls ass for a bike. the 3540 and v3 mxus are pretty much the same motor performance at the volts and amps im running. 17s4p/80amp battery running at 40 amps and bike weighs 70lbs.

check out the Norco atomic in the build thread, its a mid drive or the sinister r9 that's a v3 build with mc rims
Yeah I will stick to bicycle rims for now then, but mxus 4t or 5t is still in my list, controller wise I am indecided between the phaserunner and sabvton, sabvton being the cheapest option. Weight wise bike itself now is 13kg+ will be 10kg for motor and another about 10 for battery, 30kg= just under 70lb, is quite reasonable...

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Re: Help and advice for a 3kw ebike build

Post by markz » Jan 21 2020 9:18pm

Toss a coin on your controller choice.

Phaserunner is backed up with genuine reputable customer service.
Will it be the same with Sabvton?

gursi123   100 µW

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Re: Help and advice for a 3kw ebike build

Post by gursi123 » Jan 25 2020 5:00pm

markz wrote:
Jan 21 2020 9:18pm
Toss a coin on your controller choice.

Phaserunner is backed up with genuine reputable customer service.
Will it be the same with Sabvton?
I am just gonna save money and get a decent square wave non programmable controller for now, once everything is built after a few hundred miles I will upgrade it to phaserunner. I ll use the money saved to get a good battery pack intead I think

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Re: Help and advice for a 3kw ebike build

Post by markz » Jan 25 2020 8:26pm

I have purchased a lot from these guys
https://evfittinggreentime.aliexpress.c ... 248317.1_0

hksunwin on ebay has some cheap controllers
https://www.ebay.ca/sch/m.html?_odkw=eb ... r&_sacat=0

Lots of info on them, you can try out modifying the shunts, you can change the LVC to anything you want in the LVC resistor network on the pcb
viewtopic.php?f=2&t=71128&p=1510654&hil ... n#p1510654

gursi123 wrote:
Jan 25 2020 5:00pm
I am just gonna save money and get a decent square wave non programmable controller for now, once everything is built after a few hundred miles I will upgrade it to phaserunner. I ll use the money saved to get a good battery pack intead I think

gursi123   100 µW

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Re: Help and advice for a 3kw ebike build

Post by gursi123 » Jan 28 2020 5:35pm

markz wrote:
Jan 25 2020 8:26pm
I have purchased a lot from these guys
https://evfittinggreentime.aliexpress.c ... 248317.1_0

hksunwin on ebay has some cheap controllers
https://www.ebay.ca/sch/m.html?_odkw=eb ... r&_sacat=0

Lots of info on them, you can try out modifying the shunts, you can change the LVC to anything you want in the LVC resistor network on the pcb
viewtopic.php?f=2&t=71128&p=1510654&hil ... n#p1510654

gursi123 wrote:
Jan 25 2020 5:00pm
I am just gonna save money and get a decent square wave non programmable controller for now, once everything is built after a few hundred miles I will upgrade it to phaserunner. I ll use the money saved to get a good battery pack intead I think
Valuable links, thanks!

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