Controller Upgrade?

IrishAllTerrrain

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I have a M2S All Terrain R750 FS (they are made in NC). It has a Bafang rear hub BF RMG06 48v750W(6) 26-200807046-6

I hear if you add a 35amp controller and larger battery you can make these perform better. I however do not know anything about ebikes so, not sure which controller to get. Can anyone tell me how to determine which controller to get. I would love to just swap the controller out and nothgin else.
M2S All Terrain R750 FS.png
Bafang Motor.jpg
Controller.jpg
 
IF repeat IF your motor is NOT GETTING ENOUGH AMPS, then supplying more amps will likely make it perform better. HOWEVER, if your motor IS getting enough amps, being able to supply more with do nothing at all.

Next, if the motor DOES need more amps, and the controller supplies them, they do not come out of thin air, the battery has to be able to supply them. It will discharge faster, not live as long, and, with the 10AH battery you have, it will likely become completely unusable in a very short period of time.

TANSTAAFL

If you go to a higher voltage controller, and matching battery, it will ABSOLUTELY and WITHOUT QUESTION go faster.

Voltage is speed, amps are load. Weight, hills, acceleration.
 
The KT 35a controller is the one that has been used for upping the performance of the fat 750w Bafang for many years. Do that and a 52v battery and its about a 32 mph bike. The 35a controller is doubtless bigger than the one you have now. Its not going to fit in that little box on your seat tube. You'll have to remove the box and do your own mount, which is not difficult if you are handy with tools and know your way around the hardware store's nut and bolt section.

Also there's no telling what connectors your manufacturer used. HIGO? Which HIGO? The 35a KT controllers at ElectroBikeWorld use black HIGO throttle connectors and most others use the yellow. And for instance on the Sondors bikes they reversed the gender on the PAS plugs so people would not mistake the throttle connection for the PAS and plug them in wrong. So... expect to have to pay attention to this and maybe replace a throttle or something similar. Not difficult but you need a DIY mindset and some patience. Especially if your manufacturer used JST plugs and then you have to go to AliExpress to get a controller to try out.

However.. Bafang will make a motor that has just about anything said on the outer casing if the order from the customer is big enough. Rad Power Bikes is infamous for taking 500w motors, putting the big plug of the full size 750w motor on them and calling that a 750. Which plug does your motor have? You'll need to know. If its the 'little' one then you don't have a real 750, and instead you want to buy the KT 25a controller thats made for that lesser fudged version.

More amps will increase acceleration off the line. But leaving the voltage as-is from your battery will leave top speed as-is. Replacing the battery, given its built into your frame, is a much more difficult process than if you just had a triangle bag and could swap in a new one.

If you are serious about more speed, EBW sells a 60v compatible KT controller that should only be used with a 'real' 750w G060 fat motor. You will need 60v capable components (controller, battery and display) that they will sell you. You would pull your existing battery, sell it and you have a 40 mph bike with that gear. Make sure you upgrade the brakes.
 
My E-CELLS Super Monarch Crown has two wheel drive (BAFANG 52V 750W motors) and uses a 52V, 44a, 18 MOFSETS controller with two cooling fin arrays.
Since this bike was a bit "overbuilt" in quality I'm hoping this controller is entirely adequate. The bike has a 20ah downtube battery and a 15a rear rack battery. Both are Samsung.

BTW, I don't need more speed. I can easily do 38 mph on flat pavement in 2 wheel drive. It's low speed torque I want for dirt trails and heavy loads. As well, Dave Cleveland, the owner of E-CELLS, designed this bike to be durable so I feel pretty sure the controller is OK.
 
Torque and speed are a trade-off. With your current setup, likely no way to feasibly get more power on the low end while keeping the top speed.

40 amp at 50V is 2,000 watts. Likely your motors would only survive that for a brief period, and only a few of those.

You say "controller", as in ONE, singular, which would mean only 22amps per motor. Still over a thousand watts per motor but likely much more survivable. Look into the "shunt mod", which can give you a free amp boost.

Change your wheels from 26" to 24" would likely do it, essentially putting the bike into a lower gear. You would loose some top end speed.
 
Thanks, I will absolutely get my hub motors laced up to 24" wheels the next time one of the motors goes out. I need low end grunt much more than speed.
 
(BAFANG 52V 750W motors) and uses a 52V, 44a, 18 MOFSETS controller.
Since this bike was a bit "overbuilt" in quality I'm hoping this controller is entirely adequate.
Thats a good characterization. Its not particularly powerful for two motors, but its strong enough to give the impression of some decent oomph, and so far, so good in terms of suffering the well-known dangers commonly faced by powerful motors on suspension forks.

Bear in mind the controllers I was talking about above were per wheel, so when I was building dual-hub bikes (Bafang G060 750w, 4S/52v battery) each axle is being fed 35a peak, for a total of 70. You are running a single controller between the two and I am guessing doing a 60/40 split. Possibly 70/30. 70/30 would still give you 13a in front. Thats weak enough it seems to keep from needing the ordinarily required torque arms and solid fork. And riders who don't have a technical background likely won't know the difference - I found the sweet spot on dirt trails for power consumption and traction was about 250w to the front wheel - go too high and you end up risking issues when you pop a wheel up and it comes down facing a different direction.


Regardless of the split, I have built enough 2wd ebikes and seen so many front motor failures from other builders (more than 'dozens' but not as many as 'hundreds') I would never do one on a front suspension fork. I did have to use one myself for a month or so on an emergency basis and saw firsthand some of the stress risks.
 
I have a M2S All Terrain R750 FS (they are made in NC). It has a Bafang rear hub BF RMG06 48v750W(6) 26-200807046-6

I hear if you add a 35amp controller and larger battery you can make these perform better. I however do not know anything about ebikes so, not sure which controller to get. Can anyone tell me how to determine which controller to get. I would love to just swap the controller out and nothgin else. View attachment 9058View attachment 9059View attachment 9061
I also have a couple of M2S All Terrain HT750. I also heard you can upgrade the controller to 35amps, and get a new display and make it work. Would you happen to know where I can get this setup? I had a 25Amp controller that came with the bike. That controller stopped working, and I had to order a new one from M2S. Well the new controller they sent me only has a Max Current of 15Amps. The bike doesn't perform like it use to. I called M2S, they tell me that is the only controller they have for replacement. They come in batches, and don't know what they are going to get next. So now with this much lower torque level I need to find a higher amp controller. Please help. Thanks!
 
I also have a couple of M2S All Terrain HT750. I also heard you can upgrade the controller to 35amps, and get a new display and make it work. Would you happen to know where I can get this setup? I had a 25Amp controller that came with the bike. That controller stopped working, and I had to order a new one from M2S. Well the new controller they sent me only has a Max Current of 15Amps. The bike doesn't perform like it use to. I called M2S, they tell me that is the only controller they have for replacement. They come in batches, and don't know what they are going to get next. So now with this much lower torque level I need to find a higher amp controller. Please help. Thanks!
Did you ever figure out which controller to use? I have an m2s and am now trying to do the same thing! Any help would be greatly appreciated!!
 
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