All Terrain 750 Cold Weather Issue

tommyc803

New Member
I bought an M2S all terrain 750 to get me places for bow hunting. I live in Wisconsin. The bike works great if I keep it in the house at 70 degrees, it gets me to where I need to go. Usually I hunt a couple of hours and leave the bike secured to a tree. Everytime I go to leave and the temp is below 45 degrees the display and lights power on but when I use pedal assist or throttle only the rear hub gets power for 1/16 of a second and stops, I'm forced to ride it home the old fashion way. As soon as I bring it in to warm up it works fine. Battery is always charged as well. I'm leaning towards the controller or rear hub motor as obviously having an issue with below 45 degrees. Anybody have a solution? I haven't received an answer from M2S to remedy the issue. I have a total of 40 miles on the bike. Half of which have been human power only. Please let me know if you have a solution, as I don't know what I can do.

Thanks,

Tom C
 

Klein Rider

Member
Hey, when motor is not working are you seeing the 'engine' symbol in the display screen?

Also make sure the brake lever is not hung up by gloves etc... brake levers have a switch inside (motor inhibitor).

I've ridden my R750 down to 35° with no problems
 

tommyc803

New Member
I only see the engine symbol when I apply pressure to the brakes. I'm going to try keeping the battery warm with disposable hand warmers and see what happens, we are in the 20s now with highs in the mid 30s I should be able to diagnose that it is either 1 of those 3 major components but it will take a little time. Thank you for your reply, I appreciate it!
 

Frankie_In_Alaska

New Member
Any updates on whether it's working better in the cold? I'm in Alaska and pondering getting one but if it can't handle 0-25 degrees for 2 hours, then I'm not sure it's a great option. I plan on keeping the battery warm until it's time to go biking (storing battery in house, keeping it in the car on the way to the trailhead, etc.).
 

tommyc803

New Member
I do have an update, left the battery inside and the bike outside in the cold a few different mornings, attached the nice warm battery and just get a split second of power to barely turn the wheel and it quits. This leads me to believe the battery is not the issue, its either the controller or the motor. Tested putting disposable hand warmers on the controller while the bike sat in the cold for two hours during hunting, worked fine when I got back on it. Leads me to believe its a bad controller. Contacted M2S bikes about getting a new controller, even purchasing one and haven't heard back, that was a month ago!!
 

rich c

Well-Known Member
Curious how cold could effect a solid state device. Unless maybe a connector is shrinking from the cold. I'd try one more test. Remove the controller and bring the eBike with battery inside, leave the controller outside. Put it back together and see what happens.
 

Ravi Kempaiah

Well-Known Member
Extreme cold can affect bearings, seals and add road salt to the mix, it can degrade some of the contact points.

The gears inside the motor will have a thin layer of lubricant to keep the friction low and lubricant viscosity changes in extreme cold but lack of power indicates it is something to do with contact points.
 

harryS

Well-Known Member
This could be a bad solder joint, and some component lifts a lead off the circuit board as it contracts in the cold. An EE's nightmare.

There's not much electronics in most motors. Usually three or four 3 pin sensors mounted on a circuit board. Most likely a new controller fixes it.
 

tommyc803

New Member
Anybody know where I can get a new controller for the M2S all terrain rear hub 750? I have tried contacting them numerous times and haven't received a reply.
 

Rob Bay

New Member
I have an R750 and the only thing that has ever given trouble is the controller wire. My gut feeling is there is a short in the controller wire which is more pronounced when it is cold. Lithium batteries don't like the cold either. I get variably maybe 60-70 percent of the range and speed when temp is under say 50 degrees.
 

tommyc803

New Member
Thanks for the replys I was able to get them to answer on Facebook, new controller is on the way, in regards to the wire- Is there a spec available to upgrade from a different vendor?