ebike speed upgrade

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pocketplayer   1 µW

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ebike speed upgrade

Post by pocketplayer » Jan 19 2021 4:00pm

Hello everyone,

I would like to know some opinions/recommendations about upgrading my ebike.
Currently i own a "Klever x speed pure' ebike. it has the following specs:
  • Wheel size 27.5"
  • speed 28 mph
  • hub power 600 W
  • torque 49 Nm
  • Hydraulic disc brakes - Magura MT4e (180 mm)
  • Battery 48V 850 Wh
  • Gears Shimano Deore XT 10-speed
Image


I would like to upgrade the speed. My goal would be top speed of 40 mph (including an effort by the driver on the pedals).
The speed is now limited by the controller. The speed is measured from the hall sensors (counting pulses) so only a software modification could remove the speed limit. Since its not open source I don't think that's easy to achieve.

my requirements are as follows:
  • keep current Battery + mounting system
  • keep current brake levers ( they are equipped with a sensor that detect if the brake is pressed)
  • keep the 10 gears available
  • keep the Hydraulic disc brakes
  • keep rotation sensor at the crank
  • no use of a throttle lever, motor assistance must be based on the selected assist level on the LCD + input of the rotation sensor
  • nice to have; also include torque sensor input to determine level of assistance (torque sensor in rear dropout)

i was thinking about buying a kit with a 1500 Watt 27,5 inch rear wheel, LCD and controller.
But i could not find such kit for a 10 speed cassette, also I'm not encountered a controller that is not making use of a throttle lever. do you guys have any recommendation for my requirements? or maybe any a complete other idea to achieve a higher top speed (mounting a bigger rear wheel is not possible because of the space between the frame and wheel).

Thanks in advance

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motomech   1.21 GW

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Re: ebike speed upgrade

Post by motomech » Jan 19 2021 6:33pm

do you guys have any recommendation for my requirements?
Yeah, sell that perfectly good ebike, buy a newish high quality downhill bike w/ full suspension and big brk.s. Install a really big rear hub motor like a QS250, Clyte or a Crown;
https://em3ev.com/shop/crystalyte-kit/
Run it w/ a 72 Volt pack of lg. capacity and that should get you 40 MPH.
Quite a few builds like that on here that a search will bring up
No pedal input @ 40 MPH.
Last edited by motomech on Jan 19 2021 7:25pm, edited 1 time in total.
Motomech '11 Motobecane Fathom team, frt. mounted, recycled SWX02 from a Jump rental, 14S (52V nom.) Turnigy LiPoly, PSW Power 9-FET 20A controller. Mean Well HLG-320H-54A, Schwalbe Marathon's, 27 to 28 MPH.

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motomech   1.21 GW

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Re: ebike speed upgrade

Post by motomech » Jan 19 2021 7:23pm

There's several active threads on 'bout high-speed build on this page right now.
Search MadRhino's posts and that will lead you to lot's of high-speed builds.
Motomech '11 Motobecane Fathom team, frt. mounted, recycled SWX02 from a Jump rental, 14S (52V nom.) Turnigy LiPoly, PSW Power 9-FET 20A controller. Mean Well HLG-320H-54A, Schwalbe Marathon's, 27 to 28 MPH.

markz   100 GW

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Re: ebike speed upgrade

Post by markz » Jan 19 2021 8:19pm

I would look into seeing how much money you can get if you sold that ebike.
Then I'd look into if any part of that ebike is proprietary, especially the battery.
The motor you could buy a new generic controller and hook it up, but thats $40. Its the battery that will cost the most, so if you can't use that battery to make your own ebike, then sell it and build your own ebike.


pocketplayer wrote:
Jan 19 2021 4:00pm
Hello everyone,
I would like to know some opinions/recommendations about upgrading my ebike.

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E-HP   1 MW

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Re: ebike speed upgrade

Post by E-HP » Jan 19 2021 11:07pm

pocketplayer wrote:
Jan 19 2021 4:00pm

I would like to upgrade the speed. My goal would be top speed of 40 mph (including an effort by the driver on the pedals).
The speed is now limited by the controller.
i was thinking about buying a kit with a 1500 Watt 27,5 inch rear wheel, LCD and controller.
But i could not find such kit for a 10 speed cassette, also I'm not encountered a controller that is not making use of a throttle lever. do you guys have any recommendation for my requirements? or maybe any a complete other idea to achieve a higher top speed (mounting a bigger rear wheel is not possible because of the space between the frame and wheel).

Thanks in advance
You'll need to change out most of your components to get to 40 mph, or at least change out the controller and up the battery voltage to around 22S.

fatty   100 W

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Re: ebike speed upgrade

Post by fatty » Jan 20 2021 4:35am

pocketplayer wrote:
Jan 19 2021 4:00pm
I would like to upgrade the speed. My goal would be top speed of 40 mph (including an effort by the driver on the pedals).
40mph on MTB, upright will require 2250W. If the driver inputs 250W, you'll need 2000W from motor.

If you can fit a 27.5" x 70mm tire, tire circumference is 2275mm or 7.46ft.
40mph is 3520fps, so your motor needs a load RPM of 472, so divide by 90% for no-load RPM of 525. Divide no-load RPM of 525 by battery voltage of 48V = look for a motor with kV ~11 and 2000W.

Divide 2000W by 85% efficiency = 2350W battery watts, divide by 48V = 50A. So look for a controller that can take 50A battery amps and output 2350W.

pocketplayer   1 µW

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Re: ebike speed upgrade

Post by pocketplayer » Jan 21 2021 5:29am

Thanks everyone for your input.

I gave it some thought and came up with a new 'road map'. i have decided that i want to keep (and modify) my current bike.
instead of done all the modifications all at once, i want to do it in phase. This is to gain some experience with the result of the modifications (its not the cheapest way, but i give lower priority to that).

I was thinking to do it as follows;

  1. Upgrade the controller + LCD
    reason Unlock full potential of current installed rear hub. The hub is equipped with a temp sensor. this input will be the limiting factor ( i don't expected a big increment of speed, but i think 31 mph is reachable)
    requirements
    Support the current 48V battery, but also the new 72V (feature) battery.
    Handle a variety of rear hubs:
    The current installed 600watt hub,
    Feature hub 1; +/- 1500 Watt,
    Feature hub 2; +/- QS205 3000W

    Desired product my eye has fallen onto the following controller http://powervelocity.com/home/48-18f-eb ... e-8kw.html
    I am really charmed by the fact that you use your phone as display. it supporting a wide range of operating voltage and can handle battery currents up to 70A (which must be enough for a QS205 hub)
    The only thing is that i don't see a PAS/torque sensor mentioned as supported, it has a throttle input which i think can be used with some modifications? Also no mention is given for a temp sensor input.

    Is this a controller you guys recommend? or otherwise have other suggestions where your phone can be used as a display?
  2. Upgrade the rear hub
    Install a 1500 Watt hub motor. It would be nice if this hub motor supports 48V as well as 72V.
    Desired product not found jet. Any suggestions?
    .
  3. Upgrade the battery
    Build myself a big 22s battery
  4. Upgrade the rear hub
    if I'm still hungry for more speed, then i could update the rear hub to a brutal QS205 3000W

Let me know what you think about this plan!

Manbeer   100 W

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Re: ebike speed upgrade

Post by Manbeer » Jan 21 2021 7:11am

That looks like a direct drive hub, i would say that is probably the strongest link in the system as far as handling the speed increase. Chances are it can take double to triple the power assuming they took and relabel a typical off the shelf DD motor

Controller won't really do anything to help increase your top speed. you can increase amps, so if it is speed limited because you are strugging up hills maybe but you won't gain any top end on that alone, you mostly would just need it so you can run a higher voltage battery down the road. In fact, you may find that a larger controller has to be throttled back pretty hard to play nice with the battery thats on there. speaking of throttles, if you replaced the controller with an aftermarket one, you can leave the throttle unplugged if you desire

Really, the battery is the main factor holding back the top speed. it is also the most expensive part of the build that requires the most care. without changing it, the only other way to get to 40 would be using a motor with a super fast winding and it would burn up as soon as you ride a few miles or hit a few hills.
It WOULD be possible to make a battery box thats a similar style that fills up the frame and fits a 72v battery so thats one thing going for you, but its a nice bike so it seems like a waste to mod it in that way. I guess in my younger years, i have been guilty of doing the same thing with cars though

TLDR,
Get a 72v battery from someone reputable like em3ev,
get a good old generic 30-40 controller, overdrive the heck out of the motor on there. battery probably wont be cheap

pocketplayer   1 µW

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Re: ebike speed upgrade

Post by pocketplayer » Jan 21 2021 7:38am

Manbeer wrote:
Jan 21 2021 7:11am
Controller won't really do anything to help increase your top speed. you can increase amps, so if it is speed limited because you are strugging up hills maybe but you won't gain any top end on that alone.
Currently the software on the controller is limiting the speed limit to 28 mph (because of legal reasons). It doesn't matter if you go up hill, or have it running lifted from the ground the bike easily reach the topspeed and stops with support. So installing an after market controller would unlock the full potential of the motor.
Manbeer wrote:
Jan 21 2021 7:11am
Really, the battery is the main factor holding back the top speed. it is also the most expensive part of the build that requires the most care. without changing it, the only other way to get to 40 would be using a motor with a super fast winding and it would burn up as soon as you ride a few miles or hit a few hills.
It WOULD be possible to make a battery box thats a similar style that fills up the frame and fits a 72v battery so thats one thing going for you, but its a nice bike so it seems like a waste to mod it in that way. I guess in my younger years, i have been guilty of doing the same thing with cars though
the 40 mph is the ultimate goal, but that does not have to be achieved immediately, there may be steps in between. I will do more investigating about the capability's of the current battery (check spec of the used cells and BMS). Based on that the max amp output can be determined. If that's the limiting factor for a 1500 watt hub, i will replace the battery first.

the_nitro_addic   100 µW

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Re: ebike speed upgrade

Post by the_nitro_addic » Jan 21 2021 8:21am

There is a mid drive motor called the bafang BBSHD which is a great way to go. It's a very popular choice, and I myself have one. 1000W of power will get you to 40. You can get a 72v battery with the kit, although I used lipo batteries that I ran in series making it 18s which translates to 72v. The motor is great for everyday use, such as riding to work or around town, although you can take it off road no problem. There's a little bit more to it than a hub motor, but it's well worth it. Luna cycles cells the entire kit on their site. Everything you need for that motor is on the website.

Manbeer   100 W

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Re: ebike speed upgrade

Post by Manbeer » Jan 21 2021 9:22am

the bbshd is actually an interesting idea...if he were to ditch the factory wheels, he could offset all the weight difference too. may even be a few pounds lighter. unless the battery has some sort of proprietary communication with the oem controller etc it would probably be ok to run that motor on it in the interim too

OP, even if there is a limiter on the controller, I think you'd be hard-pressed to get any real gain out of it, The motor just isn't going to spin any faster on 48v. Maybe if it was limited by wind resistance and drag Add more amperage could overcome that it would be a different story. Thinking of the typical DD bike i built a while back, at a similar level of power, High 20s to maybe 30 to 31mph was about as good as you would get on a fully charged pack contributing significantly. Beyond that, no matter what you do, until you up the voltage you're at the point of diminishing returns. I've seen bikes with a much lower limit, in that case it may be worth upgrading but given the specs on that bike, you are not really going to get any benefit from a controller

Edit, I just saw in your second post that you would be OK with 31 mph speed in doing a controller upgrade. If that's the case it may be achievable with a lot of pedaling but if you are willing to do a significant portion of the work I don't see why it would be out of the question. You may consider gearing up with a slightly larger chain ring as well

60kmh   10 µW

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Re: ebike speed upgrade

Post by 60kmh » Jan 23 2021 2:59pm

You could may be introduce a ebikes.ca Phaserunner controller and use field weakening.

Phaserunner base on your cable connection:
https://ebikes.ca/shop/electric-bicycle ... oller.html
https://ebikes.ca/shop/electric-bicycle ... r-l10.html

The controller would get you out of the factory lock out on speed.

The field weakening would give you higher output from the motor.

If it is possible add Statorade to your motor to stop it from over heating.
https://ebikes.ca/shop/electric-bicycle ... orade.html
Statorade is injected into a direct drive motor and helps to transfer heat away from the motor stator to the motor housing.
https://ebikes.ca/product-info/grin-pro ... orade.html

Keep in mind the distance of you commute.
Depending you will get less distance the harder you push your motor.

At a future time you could update your battery to 72 volt.

Keep in mind, depending on the roads you ride on, 40 mph will take a toll on you rims and other bike components. Having fatter tires is a good idea as you add speed. I run a GMAC10T+PhaseR+52volt/30Ah battery+CA3. I run field weakening around 10A-15A and run flats around 60kmh so around 40mph. There are a lot of small pot hole where I ride and at night you don't always see them. I am now running 2.10 Schwalbe 365 four season tires now which are better, but I still do a lot of rim truing.

CycleAnalyst
https://ebikes.ca/shop/electric-bicycle ... lysts.html

the_nitro_addic   100 µW

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Re: ebike speed upgrade

Post by the_nitro_addic » Feb 02 2021 8:48pm

60kmh wrote:
Jan 23 2021 2:59pm
You could may be introduce a ebikes.ca Phaserunner controller and use field weakening.

Phaserunner base on your cable connection:
https://ebikes.ca/shop/electric-bicycle ... oller.html
https://ebikes.ca/shop/electric-bicycle ... r-l10.html

The controller would get you out of the factory lock out on speed.

The field weakening would give you higher output from the motor.

If it is possible add Statorade to your motor to stop it from over heating.
https://ebikes.ca/shop/electric-bicycle ... orade.html
Statorade is injected into a direct drive motor and helps to transfer heat away from the motor stator to the motor housing.
https://ebikes.ca/product-info/grin-pro ... orade.html

Keep in mind the distance of you commute.
Depending you will get less distance the harder you push your motor.

At a future time you could update your battery to 72 volt.

Keep in mind, depending on the roads you ride on, 40 mph will take a toll on you rims and other bike components. Having fatter tires is a good idea as you add speed. I run a GMAC10T+PhaseR+52volt/30Ah battery+CA3. I run field weakening around 10A-15A and run flats around 60kmh so around 40mph. There are a lot of small pot hole where I ride and at night you don't always see them. I am now running 2.10 Schwalbe 365 four season tires now which are better, but I still do a lot of rim truing.

CycleAnalyst
https://ebikes.ca/shop/electric-bicycle ... lysts.html
For general riding, the bike would hold up fine at around 40mph, unless you are beating it to hell and back off road.

I am looking into the phaserunner for my current small block build on a trek fuel. I might buy one, or go with the nuclear controllers.

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E-HP   1 MW

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Re: ebike speed upgrade

Post by E-HP » Feb 02 2021 10:08pm

You'll need to at least add front suspension and a suspension seat post if you're riding above 35mph. It doesn't take long to figure that out, but hopefully before crashing.

I have the controller your linked. The 200 phase amp limit is nice. I have a Cycle Analyst set up for the PAS and to tame the throttle. I stopped using PAS about 6 months ago, but the CA is still worth it for the features.

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