Anyone replaced the controller of a 700 or Cafe Cruiser?

[Ridersofthenorm]

I have a Cafe Cruiser, I love the bike but I need a bigger display. Also, I do not like the current limit at 18. I live in a windy area with hills, don't have the best knees these days and so I need as many amps as I can get.

I read that the 700 and Cafe Cruiser use similar or even the same hardware. Has anyone had to reprogram a display for these bikes? Can you tell me your settings? I don't know how many magnets the PAS/Motor has or the gear ratio. I'm assuming it's going to be 16 magnets for the motor and a 5:1 ratio as that seems to be common for Bafang geared hubs.

 

[Slaphappygamer]

YES!! I have the 700 series. I replaced my controller and display with this kit.

US $31.77 20％ Off | 36V 48V 500W 25A Electric Bicycle Brushless 9 Mosfet Sine Wave Controller with KT LCD3 LCD8 Display Panel Ebike Accessories

https://a.aliexpress.com/_mtUhPVo

I got the LCD8H display. To my surprise, it came with a usb port.

I upgraded for similar reasons, lots of steep hills in my area and it can be very windy.

The 25a controller is a hair larger, but it still fits in the downtube. I noticed more heat on my phase wires and shortened them. Do not just jam the large phase wires in the downtube. I also installed MT60 connectors that are rated for higher current. Now my phase wires don’t get as hot, just warm. When I did strip the wire back, I noticed some of the insulation had begun to, slightly, melt. I’m glad I resolved that and can ride more confidently.

 

[Ridersofthenorm]

YES!! I have the 700 series. I replaced my controller and display with this kit.

US $31.77 20％ Off | 36V 48V 500W 25A Electric Bicycle Brushless 9 Mosfet Sine Wave Controller with KT LCD3 LCD8 Display Panel Ebike Accessories

https://a.aliexpress.com/_mtUhPVo

I got the LCD8H display. To my surprise, it came with a usb port.

I upgraded for similar reasons, lots of steep hills in my area and it can be very windy.

The 25a controller is a hair larger, but it still fits in the downtube. I noticed more heat on my phase wires and shortened them. Do not just jam the large phase wires in the downtube. I also installed MT60 connectors that are rated for higher current. Now my phase wires don’t get as hot, just warm. When I did strip the wire back, I noticed some of the insulation had begun to, slightly, melt. I’m glad I resolved that and can ride more confidently.

Thanks a lot. Would you be able to tell me your display settings for the magnets and gear ratio?

 

[Slaphappygamer]

Here are my current settings.

My motor magnet setting (P1) is 86. Then again, I have a different motor than you. The manual explains “motor gear reduction ratio×number of rotor magnet pieces, just rounding if there’s any decimal.”. Yours should be 80 (16x5).

 

[AHicks]

Here are my current settings.



My motor magnet setting (P1) is 86. Then again, I have a different motor than you. The manual explains “motor gear reduction ratio×number of rotor magnet pieces, just rounding if there’s any decimal.”. Yours should be 80 (16x5).

Or whatever it takes to get the speedo close to accurate. Something you can mess with without fear of messing anything (but the speedo reading) up.

 

[Slaphappygamer]

True! I played around with this setting until I found this working for me.

 

[Ridersofthenorm]

Thanks a lot for the info. The controller arrives today so I'll be setting that up.

Took the bike out last night and it really struggles to maintain 18mph even on the small hills here and me lightly pedaling. Not sure if there's something wrong with this bike or if they not only have a speed limit but a throttle limit.

It is weird because I have another bike that is basically the same hardware, same motor but an unrestricted 22a controller. It maintains 25mph on just throttle with me only needing to assist it on hills. On flat it'll even do 28-32mph depending on wind conditions/battery charge. Meanwhile, 24mph requires a flat road with no wind and me pedaling quite a bit harder than my other bike.

At 18A, just 4a less, this thing feels very weak for my area compared to my other home build bike. Really think there's something else being limited but guess I'll see tonight.

 

[Slaphappygamer]

Yea, at just a 4 amp difference, you feel it in the power delivery. Especially going up hill. I highly recommend shortening the phase wires as much as you can and being sure to use connectors can handle the current. Otherwise, you’ll get burning plastic smell after your long hauls.

 

[teskow]

Yea, at just a 4 amp difference, you feel it in the power delivery. Especially going up hill. I highly recommend shortening the phase wires as much as you can and being sure to use connectors can handle the current. Otherwise, you’ll get burning plastic smell after your long hauls.

Connectors are definitely a weak spot in an electrical connection. They are most likely get warm or overheat before the wire will. A quality solder connection shrink wrapped is far superior and is my choice whenever possible. It will not heat up corrode or fail and they are easy to cut and re-solder if you need to change out something in the future.

 

[Slaphappygamer]

Connectors are definitely a weak spot in an electrical connection. They are most likely get warm or overheat before the wire will. A quality solder connection shrink wrapped is far superior and is my choice whenever possible. It will not heat up corrode or fail and they are easy to cut and re-solder if you need to change out something in the future.

I was actually considering that method. I don’t expect to remove my controller much, so I may end up using this method.

 

[Ridersofthenorm]

Wellp, turns out the pictures of the controller I bought were rather inaccurate and even the diagram it came with isn't for the correct controller lol. It has the correct wires but they are all the same plug (or gender I guess, that always sounds funny to me).

So, my brake cables from the bike are male for example and the controller's cable is also male, same for the lights, same for PAS, etc etc. (Why can't we all agree on one standard?)

Rather than wait another month for another controller, I'm going to be doing a ton of soldering today. I would use adapters but this controller is already a tough fit and there would simply not be any room as basically every cable would need an adapter and the controller is also a cm or 2 larger than the other. So filling the tube with connectors isn't gonna go well.

Fml.

Will update tonight.

 

[Slaphappygamer]

Or you can get a kit, similar to this

Glarks 1940Pcs 2.5mm Pitch 2/3/4/5/6/7/8/9 Pin Male and Female Plug Housing and Male/Female Pin Header Perfectly Compatible with JST-SM Connector Assortment Kit https://a.co/d/izVSKZ9

….then make your own connections, rather than adapters.

 

[Ridersofthenorm]

Or you can get a kit, similar to this

Glarks 1940Pcs 2.5mm Pitch 2/3/4/5/6/7/8/9 Pin Male and Female Plug Housing and Male/Female Pin Header Perfectly Compatible with JST-SM Connector Assortment Kit https://a.co/d/izVSKZ9

….then make your own connections, rather than adapters.

Damn that is a really good set. I'm definitely getting that.

 

[Slaphappygamer]

Don’t forget the crimper and checkout how to make the connection. It’s a bit more than I was expecting.

 

[Ridersofthenorm]

Got a similar set at an electronics store and got the bike running. It's a lot better now but I'm pretty mad.

The controller I bought is 22a but is limited to 20a via the S900 display. After waiting a month for the controller, hours and hours of soldering, cable management, and even filing down the aluminum battery mounting bracket holder because the controller is 1cm too long, I learn that the display limits the current to 20a.

I don't get it. Why sell a 22a controller when your display limits it to 20a? If I wanted a 20a controller, I'd have bought that and not had to file the mounting bracket down. I tried a KT LCD3 display and an S866 display on the controller and no lights/throttle. So it seems like it's locked to the display it came with. Unless anyone with more knowledge knows what display will work with a "DC Moto Controller By Lithium Battery" controller.

It looks like I'll have to do all of this over again. I'm not sure if there is a display that will work or if there is a way to simply remove the 20a limit via modding the display. I read that some people do display mods by hooking the display up to their phone but I can't find anything on S900 editing.

I looked at KT controllers of 48v 22a, in fact my other bike has one, but it's definitely too long to fit in the tube. It needs to be under 12cm.

My fault though for not looking up the S900 manual before buying it. I just assumed that if you buy a 22a controller then you get the full 22a you paid for.

Ugh.

 

[AHicks]

Got a similar set at an electronics store and got the bike running. It's a lot better now but I'm pretty mad.

The controller I bought is 22a but is limited to 20a via the S900 display. After waiting a month for the controller, hours and hours of soldering, cable management, and even filing down the aluminum battery mounting bracket holder because the controller is 1cm too long, I learn that the display limits the current to 20a.

I don't get it. Why sell a 22a controller when your display limits it to 20a? If I wanted a 20a controller, I'd have bought that and not had to file the mounting bracket down. I tried a KT LCD3 display and an S866 display on the controller and no lights/throttle. So it seems like it's locked to the display it came with. Unless anyone with more knowledge knows what display will work with a "DC Moto Controller By Lithium Battery" controller.

It looks like I'll have to do all of this over again. I'm not sure if there is a display that will work or if there is a way to simply remove the 20a limit via modding the display. I read that some people do display mods by hooking the display up to their phone but I can't find anything on S900 editing.

I looked at KT controllers of 48v 22a, in fact my other bike has one, but it's definitely too long to fit in the tube. It needs to be under 12cm.

My fault though for not looking up the S900 manual before buying it. I just assumed that if you buy a 22a controller then you get the full 22a you paid for.

Ugh.

Self admitted KT fan here, with quite a few installs/conversions going way back. I haven't seen what you are working with, so I just wanted to share that MAYBE you can find a little extra room for a KT controller if it's installed with the wires pointed down, possibly exiting the down tube and led to an area under the crank where the connections are made in an area that's mostly out of sight. I've done this a couple of times and been very happy with the results.

I would add that there's a KT-25a available now, with the same dimensions as the older original 20a and 22a's. 22a is pretty capable, delivering nearly 1000w at wide open throttle on a couple of generic 500w geared hub bikes the wife and I are running. That's PLENTY of short term scoot to get you across a busy road for instance..... -Al

 

[Ridersofthenorm]

Self admitted KT fan here, with quite a few installs/conversions going way back. I haven't seen what you are working with, so I just wanted to share that MAYBE you can find a little extra room for a KT controller if it's installed with the wires pointed down, possibly exiting the down tube and led to an area under the crank where the connections are made in an area that's mostly out of sight. I've done this a couple of times and been very happy with the results.

I would add that there's a KT-25a available now, with the same dimensions as the older original 20a and 22a's. 22a is pretty capable, delivering nearly 1000w at wide open throttle on a couple of generic 500w geared hub bikes the wife and I are running. That's PLENTY of short term scoot to get you across a busy road for instance..... -Al

Thanks. I am currently on the hunt for that controller now. I so far only found another JN controller that is 11.8cm long but afaik, all JN controller displays are limited to 20A. Which I seriously don't understand that because they sell 35A controller models and they remind customers they can only use JN specific displays like the S866, S900 etc which have a 20A limit. So now I'm confused on who is buying these 35A controllers when they can only use 20A. I can't help but feel like I'm missing something.


As for fitting the controller in. I currently have the wires pointed down but the compartment for the cruiser is an odd shape (gets more narrow towards the bottom and has concave sides so it only fits one way) and some of the cables are at odd lengths which makes it difficult to get it into a uniform shape. I know I'm not doing a good job of explaining the situation of fitting it in lol, but it took me an exhausting several hours just to get it in, which I think I tried every possible thing I could think of until I ended up filing the bracket and it still took another hour lol.

The current controller I have in is, iirc, 11.4cm. I think maybe water plugs would help or shortening the battery connector wire. I could maybe get another 0.5-1 cm in but it's gonna be a challenge.


I know some will probably say I should just mount the controller outside, but imo, the bike looks too nice for me to hang a big controller outside of it. I have built custom ebikes like that but I want to keep this one *looking* like it's stock version.

 

[AHicks]

I know some will probably say I should just mount the controller outside, but imo, the bike looks too nice for me to hang a big controller outside of it. I have built custom ebikes like that but I want to keep this one *looking* like it's stock version.

I get it, that's my FAVORITE plan. It's got to be a sleeper! I have a 2017 RAD City (purchased new) that you would never know wasn't a production bike. Only thing is, the OEM 750w direct drive motor (total dog) was swapped for a high end MAC 12t (torque monster) geared hub, powered with a KT 35a controller, making it a sleeper extraordinaire! Totally docile, I can put somebody that's never been on an e-bike on it with total confidence - AND - it's been totally reliable since built.

Best of luck with your project! -Al

 

[Ridersofthenorm]

After several days of effort, I have decided that I will mount the new controller externally. I cannot seem to find a 22A or 25A KT controller that is below 12cm. I spent 5hrs a day for two days trying to fit a 12.6cm KT controller in. No dice.

I had ordered a brainpower controller but they listed the dimensions wrong and what arrived was a brick of a controller that also, funny enough, had a display that was locked to 20A. As far as I'm concerned, the 20A display limits that these manufacturers set on expensive high amp controllers is false advertising. Same with Ride1up listing the bike as being 22A but then limiting it to 18A. 4A below what they sold it as.

JN on AliExpress told me they limit their controllers to 20A to avoid accidents. I asked "Why do you sell 35A controllers with 20A displays? I don't understand". Their reply "Why do you ride a bike if you want to go fast? I don't understand"

Which was infuriating because it showed not only a lack of understanding of how ebikes work but also that they knowingly limit their controllers even though you're paying big bucks for the higher amps.

So after all this, I'm mentally fatigued. Have a box of controllers and will just mount a 25A KT controller now.

KT for life. Never getting any other controller again. Hopefully I save future googlers some money.

 

[Slaphappygamer]

Wow, so JN doesn’t understand that more amps is not more speed. It’s just more acceleration. They should be more upfront about this.

Glad you finally have a resolution. Though, it’s not the one you were hoping for. You can find “ebike controller boxes” or bags to better hide the wiring and controller, if needed.