LMT'D torque sensor bottom bracket

Mike N.

Active Member
I took my LMT'D to the local bike shop due to a creek in the bottom bracket. They did not have a bottom bracket wrench my size to purchase which is 44 mm 16 teeth if anyone is curious. They said they would take a look at it and they greased the bottom bracket for $15.00 which got rid of the creak. The problem was a few days later when I went for a ride the torque sensor was inop. Throttle worked fine but no pedal assist. I think they did not realize it was electrical component and pulled on it causing the black insulation to get pulled off.

There is a plug under the bottom of the battery tray to unplug first. I ordered the right size spanner on Amazon and removed it this evening. There are 6 wires under the insulation as you can see. I can't seem to feel any breaks but the red wire which I'm thinking is power has some of the copper showing through where the thin insulation has been scraped off. It might be coming in contact with the frame and grounding out. I'm going to try to reinsulate the wires and put it back to see if that fixes it. If not I have already contacted Alex at Ride1up support and they sell a replacement for $150.00 and shipping.

I do not blame the bicycle shop since they do not sell electric bikes. They were just treating it like an ordinary mechanical repair. I wish I had the right size bottom bracket wrench to begin with but now I know. I'll post to let you know if the repair works. If a wire has pulled out of the bracket itself then I'm pretty sure it is non repairable.

They sell liquid electrical tape so I'm thinking of trying that.

 

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Mike N.

Active Member
Repaired! I was giving myself very low odds on being able to repair it. Went to Lowell's this morning and purchased liquid tape and some shrink insulation but I did not use the shrink insulation. I saw some of the insulation was missing on the red power wire so just made sure all the wires were slightly separated and brushed on the insulation. Put everything back together and pushed down on the pedals and I had power.

The hardest part was reconnecting the plug to the wiring under the battery tray. They must hire children with small hands in China to reach it. It is a plug like the one going to the motor next to the chain so it will only attach one way.

While I had the bottom bracket off I removed the rubber covers of the sealed bearings and greased them good with synthetic grease. Couldn't hurt.

All well that ends well.
 

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Thombrad

New Member
Congratulations on your great work and success !! Did you happen to notice who the manufacturer of the BB torque sensor is ?
 
Region
USA
City
San Diego
I took my LMT'D to the local bike shop due to a creek in the bottom bracket. They did not have a bottom bracket wrench my size to purchase which is 44 mm 16 teeth if anyone is curious. They said they would take a look at it and they greased the bottom bracket for $15.00 which got rid of the creak. The problem was a few days later when I went for a ride the torque sensor was inop. Throttle worked fine but no pedal assist. I think they did not realize it was electrical component and pulled on it causing the black insulation to get pulled off.

There is a plug under the bottom of the battery tray to unplug first. I ordered the right size spanner on Amazon and removed it this evening. There are 6 wires under the insulation as you can see. I can't seem to feel any breaks but the red wire which I'm thinking is power has some of the copper showing through where the thin insulation has been scraped off. It might be coming in contact with the frame and grounding out. I'm going to try to reinsulate the wires and put it back to see if that fixes it. If not I have already contacted Alex at Ride1up support and they sell a replacement for $150.00 and shipping.

I do not blame the bicycle shop since they do not sell electric bikes. They were just treating it like an ordinary mechanical repair. I wish I had the right size bottom bracket wrench to begin with but now I know. I'll post to let you know if the repair works. If a wire has pulled out of the bracket itself then I'm pretty sure it is non repairable.

They sell liquid electrical tape so I'm thinking of trying that.

My renown for faux paus preceding me, it's been several months, but I'm curious to follow up and ask if the repair is holding up?
Those photo's are very helpful to anyone delving into the TS, like me.
Now that the Ltd's TS is discontinued, owners having to locate suitable replacements are a foreseeable event.
The TS appears to be generic, with specs ordered up by R1U. Perhaps they'll help us document and archive the info.
I appreciate your common sense approach/ solution/ attitude. Turning that shaft 1/4 turn will chop the wires clean off.
3.14150... (pi) x shaft diameter, per turn = 1" shaft, rotated 1/4 of a turn will 'pull' (rip) .7853" of wire.
Big kudos to the member that pointed out repetitive failures often indicate bad installation (to re-phrase it kindly).
Shops don't know. I learn from my mistakes - and whenever possible, the success or mistakes of others.

Ride on

Fn'F
 

Sic Puppy

Member
I decided that this is the best route for dealing with the torque sensor/cadence sensor crap:
https://arielrider.com/products/x-class-52v?variant=37498729857200
My $2,200US blue ebike is due to ship in 3 weeks. 52v/18ah battery. 36mph throttle-only top speed--Motorcycle tires are awaiting the arrival of this beast. Hell Yes. Check it out on YouTube.. As for the pos BikTrix SWIFT turd muncher ebike that is now selling for an absolutely unbelievable $2,700-- I paid $1,700 for mine 12 months ago. (What a frigging canadian RIP-OFF-- either way you look at it.):
I am gradually removing/salvaging the viable SWIFT parts/components (but, NOT the rear hub MXUS motor, controller, bottom bracket torque sensor unit, and cdu-- they will all go "down the terlet", where they belong) and the then the frame will be cut up and sent the recyclers. I used a magnet to verify that it's aluminum, and not steel. Ya just can't trust those peaky 3rd world Canucks..
 
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