Hello! This is my first post in this forum. I'm building a custom e-bike on a frame I already own, but it's bottom bracket shell is incompatible with most torque sensors on the market.
The core of my question is very simple:
Is there any known setup for a bottom bracket torque sensor that fits inside a press-fit BB92 bottom bracket shell (actual width 90mm) and that is compatible with a VESC?
I am investigating the matter and I have multiple leads, but is there anyone who has seen such a thing done already? What did you/they use to accomplish it?
Most torque sensors on the market use a threaded (BSA) interface, therefor they do not fit my press-fit BB92 bottom bracket shell. I already have the bike frame with the BB92 bottom bracket shell, that will not change. I will not cut off the bottom bracket and weld a new one in. The VESC (which I already own) accepts analog input, the range of which I'm free to adjust as I best see fit.
Currently I am aware of the following angles of approach:
1) Buy two adapter plates that fit on both sides of the BB92 bracket that adapt it to BSA such as these and use an eRider T17 100mm or Sempu bottom bracket sensor (or similar).
Pros: These torque sensor outputs are known to work with VESC with minimal hassle, the issues are somewhat documented.
Cons: I have no guarantees the adapter plates will actually stay in the bracket shell without being strongly clamped together (classic problems of a press-fit). The eRider T17 is offered in basic BSA BB widths, ie. 100mm wide model is most likely to work, but I have no guarantees it sits well in my 90mm + adapter plated bottom bracket. Spacers might fix this.
2) Machine (or have my friend machine) a custom adapter for BB92 -> 100mm BSA that actually goes through the bottom bracket and screws on and clamps together, making the new 100mm BSA BB as sturdy as our machining skills allow. This is the same as 1), but possibly much more likely to handle the punishment.
3) Use on of the press-fit BB92 BB compatible torque sensors with currently unknown (to me) compatibility with VESC, like the CYC torque sensor or Mahle torque sensor. I need to ask the manufacturer / sellers about what kind of output the sensors have or if they are otherwise locked down to have an educated guess whether they are compatible. All a VESC needs is a regular e-bike throttle signal, ie. voltage modulated analog signal.
Pros: They already fit the BB92.
Cons: I am unaware of any proof that either of these work with a VESC.
4) Something else, what?
If anyone can confirm any of the ideas, great. If you have other thoughts, let me hear them. Thanks!
The core of my question is very simple:
Is there any known setup for a bottom bracket torque sensor that fits inside a press-fit BB92 bottom bracket shell (actual width 90mm) and that is compatible with a VESC?
I am investigating the matter and I have multiple leads, but is there anyone who has seen such a thing done already? What did you/they use to accomplish it?
Most torque sensors on the market use a threaded (BSA) interface, therefor they do not fit my press-fit BB92 bottom bracket shell. I already have the bike frame with the BB92 bottom bracket shell, that will not change. I will not cut off the bottom bracket and weld a new one in. The VESC (which I already own) accepts analog input, the range of which I'm free to adjust as I best see fit.
Currently I am aware of the following angles of approach:
1) Buy two adapter plates that fit on both sides of the BB92 bracket that adapt it to BSA such as these and use an eRider T17 100mm or Sempu bottom bracket sensor (or similar).
Pros: These torque sensor outputs are known to work with VESC with minimal hassle, the issues are somewhat documented.
Cons: I have no guarantees the adapter plates will actually stay in the bracket shell without being strongly clamped together (classic problems of a press-fit). The eRider T17 is offered in basic BSA BB widths, ie. 100mm wide model is most likely to work, but I have no guarantees it sits well in my 90mm + adapter plated bottom bracket. Spacers might fix this.
2) Machine (or have my friend machine) a custom adapter for BB92 -> 100mm BSA that actually goes through the bottom bracket and screws on and clamps together, making the new 100mm BSA BB as sturdy as our machining skills allow. This is the same as 1), but possibly much more likely to handle the punishment.
3) Use on of the press-fit BB92 BB compatible torque sensors with currently unknown (to me) compatibility with VESC, like the CYC torque sensor or Mahle torque sensor. I need to ask the manufacturer / sellers about what kind of output the sensors have or if they are otherwise locked down to have an educated guess whether they are compatible. All a VESC needs is a regular e-bike throttle signal, ie. voltage modulated analog signal.
Pros: They already fit the BB92.
Cons: I am unaware of any proof that either of these work with a VESC.
4) Something else, what?
If anyone can confirm any of the ideas, great. If you have other thoughts, let me hear them. Thanks!
