Repairing a stromer

Hello, I have a stromer elite and I believe that it has contoller issues.
Anyways, I took the motor appart and the controller and I don't know if it is a possibility to repair it.
I am considering some optioms while browsing the web and these forums, are interesting indeed!

I'm not so sure that I would prefer to spend much on this repair, and any upgrades might decrease the efficiency and durability of the bike!

I would have to build from scratch and perhaps.
I would like to have a bike that is durable, fast and efficient. but I think the standard is this way except for the speed could use maybe a slight upgrade.

I have two 36v 17ah batteries, so I could perhaps hook them up in series, or parrallel. Having the ability to switch from 36v to 72v on demand would be very interesting and nice to have.

I think the current motor may be able to handle these voltages, but I am concerned that it may decrease the durability and efficiency. If this is so, I would prefer to stick to 36v and if it can be made faster and more efficient that would be great! Tips please and thanks!

I wondered if it was gearless and EBR states it is.
https://electricbikereview.com/stromer/st1-elite/
Which is better on your part for the motor to be direct drive (gearless)
Hopefully your controller/battery aint proprietory and its just generic stuff put together and marketed.

You need to trouble shoot!

I believe this bike has a DD hub. DD hubs are capable of higher voltage and power, but you first need to diagnose the problem that you have.

You say that you took the motor and controller apart. That shouldn’t be necessary to find the problem. You say you have a controller problem. I presume you had tested it. What are the tests and results that you have?

When unplugged from the controller and wires ends not touching each other, does the motor spin by hand normally, feeling the slight resistance of every phase? With a multimeter, test resistance of the 3 phase wires between each other, and continuity between each of them and the axle.

The Stromers use a pretty nicely made DD hub; their vulnerabiliyt is the proprietary controller/display/torque sensor system, with the electronics inside the DD hubmotor where the heat from everything is all concentrated, baking it all nicely if it ever gets hot.


The motor itself could probably handle at least 1000w continuous, if the controller was external. I'd guess 2-3kW bursts would work well enough, if you really wanted to do it.

Voltage is irrelevant, other than that if you use twice the voltage, it'll spin at twice the speed for the same throttle input, at least when unloaded (offground). When actually riding, you won't get quite twice the speed because of air resistance and whatnot, vs the amount of total watts you put thru the system.

If you don't need the extra speed I recommend just paralleling the two battery packs, as it will make for less stress on them, and less voltage sag (meaning more power gets to the controller/motor, and less wasted as heat in the pack itself).

You can use any regular ebike controller for the motor, if you run the phase/hall wires out from inside the motor. I recommend a sensored controller, but a sensorless could do it too. True sinewave/FOC will be nice and silent, vs a trapezoid (more common) type.

Taking it apart to do this is PITA, as you ahve to take half the spokes off, tehn pull the cover off one side, then cut the wires to the built in controller puck and remove the wire bundle that was in there, and replace it with a new one that has the wires you need. You can reuse the existing bundle if you like, as long as it has three thicker wires and 5 thinner ones, doesnt' matter what colors they are.




I have one of those motors here, and the plan (once I get around to it) is to run some nice thick phase wires out the axle, along with the hall sensor wires for the built in ones, and run it off an external controller as the front wheel of SB Cruiser, in a fatbike fork (since it's a rear hubmotor it won't fit in a regular front fork). I have the parts to do it all...just not the time.

https://endless-sphere.com/forums/viewtopic.php?f=2&t=86600&p=1269985&hilit=stromer#p1269985

It's been a while, but I don't think a Stromer has much in the motor.... The torque sensor is built into the dropout feeling the chain pull, and there's a long skinny controller under the downtube.

I guess it must depend on the Stromer then--I haven't seen any like that.

Note that I haven't seen any Stromers at all in person; just around the web/forum, and the one motor/wheel I have here (and the display), that has the controller in the motor.

The ones I've seen so far use the Ultra motor like A2B; controller inside the motor. See the linked thread above, or the few of these that have any pics/info about the motor:

https://endless-sphere.com/forums/search.php?keywords=stromer&terms=all&author=&sc=1&sf=titleonly&sr=topics&sk=t&sd=d&st=0&ch=300&t=0&submit=Search

I didn't look thru all of them this time around, but when I did after getting this motor, I couldn't find any that didn't use the motor with integrated controller, out of the few that mention it.

The later generation ones might have moved away from that... now the controller is under here..



Or part of it anyway

Here's the inside of the drive side dropout... The chain pull flexes the dropout forward to press on the strain gauge. There's a tiny hole on the front side that leads to an sensitivity adjuster screw on the strain gauge (that most of the time wasn't lined up with the hole the frame which blows the whole idea of easy adjustment).
Several times I had customer ones stop working that turned out to be tiny grains of sand caught in the gap in the strain gauge, keeping it from flexing the gap closed. That took a little headscratching after checking all the normal electric type troubleshooting on the first one.

my motor of steamer st1 is broken
is and mountain 25 tdmc
have another engine that has a 3 pin connection for motor
my faulty has a 2 pin red and black can i connect this 3 pin
red and black what is the yellow wire?