FX+ 7S?

[TrekkieMike]

100% means the motor is adding the same amount of power the rider is inputting, so per other manufacturers, you’d be pedaling at the 2X level. 200% assist is adding twice the input, so that would translate to 3X elsewhere, if I understand the other convention correctly.

 

[stompandgo]

Thanks for pointing out the additional settings for the TQ motor. Using the Trek Central app, I don’t see a Support Speed option. I’m curious if that’s buried elsewhere, and if that’s contributing to the issue. I’ll investigate.

Regarding the factory settings, after initially reporting the issue, our Trek dealer had us both delete the app and start over from the factory settings to make sure we’re being consistent in our comparisons. Our eco settings are higher than factory - just checked - actually 113% each at 100 W max with pedal response at 40%. We save the 300 W max and 200% assist for the High/turbo mode which is rarely ever used - just steep hills. Probably in Eco 98-99% of the time, with the middle mode used sparingly if dragging towards the end of a ride going up a grade.

It's probably because you are on a Class 1 EMTB which is limits assist up to 20mph. Road bikes can be set up to Class 3 speeds, 28mph, but you can dial it back if you want.

I set up a lot of TQ bikes at the shop, but I also own one. It is a flat bar urban bike with effective 50mm gravel tires, and weighs 32 pounds. I weigh 165 pounds. I ride mostly in Off or Eco, using Mid and High only when needed or I feel like it. I get about 65 miles on a charge. Eco and Mid are dialed back significantly, while High is flat out. I have the Pedal Response dialed way back because I don't want the "push" that a full power motor would give you.

Here are my settings. All are set for 28mph Support Speed.

Eco: Max Power 66W, Assist 113%, Pedal Response, around 15%, between the "n" and the "s" in "Response" on the app.
Mid: Max Power 128W, Assist 140%, Pedal Response same.
High: Max Power 255W, Assist 200%, Pedal Response, same.

As always, FWIW.

 

[stompandgo]

100% means the motor is adding the same amount of power the rider is inputting, so per other manufacturers, you’d be pedaling at the 2X level. 200% assist is adding twice the input, so that would translate to 3X elsewhere, if I understand the other convention correctly.

You do, but the TQ lets the rider set the Max Power for each assist level. If the rider exceeds Max Power, it's not matching 100% of the rider power anymore.

 

[Jeremy McCreary]

You do, but the TQ lets the rider set the Max Power for each assist level. If the rider exceeds Max Power, it's not matching 100% of the rider power anymore.

Specialized assist mode tunings work the same way. Result: Motor power stops increasing beyond a certain rider power specific to the selected mode. Beyond that saturation point, rear wheel power increases with rider power watt for watt.

Detailed explanation of the Specialized approach to assist mode tuning:

Visualizing and exploring the power-sensing PAS in Specialized mid-drives — an interactive graphical model

For our more math-minded Specialized mid-drive riders, here's an interactive graphical model of your bike's tunable power-sensing pedal assist system -- hereafter, just "PAS". The model doesn't cover complex PAS responses to transient events like starting out or approaching PAS cut-off speed...

forums.electricbikereview.com

 

[rochrunner]

Here are my settings. All are set for 28mph Support Speed.

Eco: Max Power 66W, Assist 113%, Pedal Response, around 15%, between the "n" and the "s" in "Response" on the app.
Mid: Max Power 128W, Assist 140%, Pedal Response same.
High: Max Power 255W, Assist 200%, Pedal Response, same.

OK, I think that my confusion is a matter of terminology, distinguishing between how much assist is delivered proportional to your pedaling power (what Trek calls "Pedal Response") and the maximum assist that can be delivered in the mode (what Trek calls "Assist"). Correct?

 

[Jeremy McCreary]

OK, I think that my confusion is a matter of terminology,

Pretty common around here. Specialized has changed the official terminology surrounding their assist mode tuning several times, and people make up their own terms without defining them. Plus, some members write authoritatively about it without really understanding it.

Result: A total mess. If you can find detailed documentation from the manufacturer, go with that.

 

[stompandgo]

OK, I think that my confusion is a matter of terminology, distinguishing between how much assist is delivered proportional to your pedaling power (what Trek calls "Pedal Response") and the maximum assist that can be delivered in the mode (what Trek calls "Assist"). Correct?

I'd stick with the TQ terminology.

Eco: Max Power 66W, Assist 113% means the motor puts out 113% of what you are putting out up to a maximum motor power of 66 watts. Above that, it's your power +66 watts.

 

[rochrunner]

I'd stick with the TQ terminology.

Eco: Max Power 66W, Assist 113% means the motor puts out 113% of what you are putting out up to a maximum motor power of 66 watts. Above that, it's your power +66 watts.

Example: With the above settings, I'm pedaling at 50W -- which is not that much. 113% of 50 = 57W, so 50 + 57 = 107W at the crank? That's way more boost that I'm generally looking for.

Or is 113% the total power? IOW, 50W pedal effort + 13% additional = 50 + 7 = 57W output. That makes more sense to me and is basically what I'm used to.

 

[stompandgo]

The first one. 107W total is nothing on an analog bike. You can easily roll along the flats at 107W. Add a 1% grade, which is also nothing, and you're at 125-150W, and the difference is coming from your legs. You've maxed out the assist power at that setting.

Again, I'd reset to default, then tune. I'd keep the Assist% at default for Eco, and adjust the Max Power to your liking. Ride in Off and Eco for a while until you dial it in. If there are times on the flats or slight downgrades where Eco is too much, shut it off. That saves significant power. If you find yourself pushing the + button a lot, increase the max power 5W at a time. Once you have Eco dialed in, go through the same procedure with Mid for significantly higher Max Power and Assist%. I'd save High for flat out. You won't use it much, but everything the motor has is there if you need it.

Again, FWIW.