2023 Trek Domane+

Searching a bit in various forums, especially in MTB forums that use the TQ50 motor, I come across the fact that this same issue is well-known to them, and they have even received a response from the manufacturer clarifying their stance. I am attaching a YouTube link where I found the following response from TQ:

"@RobRidesEMTB
To add - the motors are near silent on descents - barely any noticeable rattles (especially compared with Shimano / Bosch)Also, TQ responded to a small number users experiencing noises. Here’s what they said:

Hey Rob! Just wanted to give you a quick heads up regarding the noise discussionsWe are currently working on this topic. It has no influence on the motor’s performance or durability and seams to be no more than a peculiarity of one of the sprag clutches of our motor. If the motor’s assist is very low (less than ~ 10W) it seams that the electric motors torque is not enough to rotate the clutch, but not fully engage it. This can lead to the weird rattling/grinding noise. The forces in such a scenario are however extremely low and do not put any mentionable wear on the internals of the motor. From everything we know and all the 1000s of field testing kilometers we have already done this issue is nothing to worry about. Nevertheless the low noise is one of our strongest USPs and we are working on a solution. We believe that some tweaks in the motor controller algorithm could reduce or even completely remove this noise. Our goal is to roll out a software update before the end of this year.
"
 
I also found this interesting discussion:

TQ HPR50 Grinding Noise

OK, I''ve just now figured the factors that produce the grind sound, for me. Any time, and for me every time, the pedal rate and force i apply on the crank fall below what's needed to activate the motor, the grind sound occurs. For example this will occur while riding on a level surface in a...
www.emtbforums.com www.emtbforums.com
 
AntonioAlfaro said:
Thank you, Jack, for your timely comment. I suppose you're referring to the ring that secures the chain sprocket to the motor shaft?. I will check.
Click to expand...
The other thing I've read about is noise from
AntonioAlfaro said:
I also found this interesting discussion:

TQ HPR50 Grinding Noise

OK, I''ve just now figured the factors that produce the grind sound, for me. Any time, and for me every time, the pedal rate and force i apply on the crank fall below what's needed to activate the motor, the grind sound occurs. For example this will occur while riding on a level surface in a...
www.emtbforums.com www.emtbforums.com
Click to expand...
Do any of these sound like your issue?
 
AntonioAlfaro said:
Jack, it's exactly the grinding sound they describe in that forum.
Click to expand...
Interesting - I'm on the fence about pulling the trigger on a Domane+ vs a Specialized Creo 2 (I have the original Creo 1, which has been magnificent, but I"d like more power and a quieter motor).

I think a noise like that might make crazy.
 
Jack Cox said:
Interesting - I'm on the fence about pulling the trigger on a Domane+ vs a Specialized Creo 2 (I have the original Creo 1, which has been magnificent, but I"d like more power and a quieter motor).

I think a noise like that might make crazy.
Click to expand...
Jack, to be honest with you, I've been very satisfied with the performance of the 2023 Domane+ SLR. It's the ideal road e-bike. Regarding the grinding noise and based on TQ's response, it reassures me a bit, and for now, I'll try to avoid the pedaling and assistance conditions that trigger it. But without a doubt, I will file the corresponding complaint with TREK since the bike is still under warranty.
The noise isn't constant or excessive. It's more concerning that something internally might be getting damaged. But according to TQ, it's not the case. What also stands out is that some users report that the issue was resolved after TREK replaced their motor with a new one.
 
I am tricking the motor. I don't allow the assistance power to drop to low levels where the grinding noise occurs. I achieve this by quickly shifting to higher gears so that my legs are always delivering power. Also, on easy segments of the route, I turn off the motor.
 
I remember watching a video of a guy who purchased an early release of this motor on a mountain bike, who experienced grinding noises on his TQ motor. I chalked it up to an early production problem and haven't heard anything concerning grinding noises since.
 
They have probably managed to mitigate that noise quite a bit, but it's still there and can occur under certain pedaling conditions. For now, I tend to think it's something intrinsic to the TQ motor and that one can learn to avoid the conditions that trigger it. Apart from that, I still love my 2023 Domane+ SL
 
For those who like real data, I conducted a test on the Domane+ SLR 2023 until the battery was completely depleted. Two purposes; 1) To determine at what battery percentage the assistance disconnects, 2) To determine the total battery capacity in Wh. During the test, I thought I would be notified in some way when the battery reached 15% remaining, but that didn't happen. The system continued to work normally regardless of the level of assistance used, and I reached 5% remaining without any issues. However, just as I passed to 4% remaining battery, the assistance cut off. The e-bike started to function like a regular bicycle. The display showed 0% battery. This is an important piece of information to consider when planning a new ride and wanting to avoid surprises. So, remember the magic number: 5%. Back at home, I started charging the battery until it was back to 100%, and the energy required for that was 335 Wh. This data is equally important in planning new routes, as it represents the actual maximum available capacity (not 360Wh as we might be tempted to think). I hope this modest measurement is useful to you. Regards.
 
AntonioAlfaro said:
So, remember the magic number: 5%.
Click to expand...
Often found on good e-bike systems as the cut-off there helps protecting the battery.
AntonioAlfaro said:
the energy required for that was 335 Wh. This data is equally important in planning new routes, as it represents the actual maximum available capacity (not 360Wh as we might be tempted to think). I hope this modest measurement is useful to you.
Click to expand...
That's why the maximum effective charge of a new Specialized SL battery is 304 Wh instead of the rated 320.
 
Coincidentally I exhausted the battery on a 54 mile ride today, from a starting charge of 92%. Only 2150feet of vertical gain, but significant chunks of the ride were takenat aggressive speeds with liberal use of Eco, and occasional use of Mid where I would usually be in Eco.

Oddly enough I set off without the Karoo 2, which reliably reports the % charge remaining throughout my rides. Today I would occasionally check for it on the TQ display.

With a handful of miles to go it reported 15% remaining, which I figured sufficient to get me back, but I was surprised to have it cut out and show 0% in the last mile. It might have dropped out at the 5% you experienced, but don't have specific evidence.

Some months back I purposely ran it to0% and vaguely recall that it did so gradually 5,4,3,2,1,0, but I could be mis-remembering.

Definitely something to monitor in the future (with the Karoo).
 
"Thank you, Rob, for your observations. I must say that before conducting this test, I was searching for information on the web, and the only thing I managed to find was an FAQ document from Trek, which is on the Domane+SLR 2023 page in the Service section. In that document, there is a very interesting answer that says: "
Are there any other special instructions for the battery?
Please note that the battery will only last to about 15% capacity the first time it is depleted. So
don’t be alarmed if the range on your first ride is a little shorter than expected. After the first
full depletion and subsequent charging, the battery management system will “learn” what it
needs to know and will deplete all the way to 0% on future rides.
Also note that any time the battery reaches less than 10% charge, the motor output will be
reduced to 110 watts. The battery level indicator will flash to indicate Low Battery mode.
".
It seems that in the first deep discharge, the system cuts off before reaching 0%, but in subsequent deep discharges, the system reaches 0%. This aligns with what you report having observed.
 
Great info - thanks to all, especially Antonio, for all the testing and reporting. I have never experienced the grinding, probably because I rarely do "catchup" pedaling - it seems I am either on or off, haha. BTW, I have been easing back into riding the bike again after going through PT for my knee pain, and most significantly, finding out I need orthotics to support my feet, which over-pronate (collapsing inward, and stressing the medial meniscus). This apparently was not a problem with narrow Q-factor road bikes, but the slightly added width of the Domane+ exacerbated the situation, especially on the left which is the foot that is the worst..

I have to say I am very happy about this turn of events, as I do love this bike. It is so solid-feeling, and rides well, even without the assist turned on (I sometimes forget, haha).
 
mtnroads said:
Great info - thanks to all, especially Antonio, for all the testing and reporting. I have never experienced the grinding, probably because I rarely do "catchup" pedaling - it seems I am either on or off, haha. BTW, I have been easing back into riding the bike again after going through PT for my knee pain, and most significantly, finding out I need orthotics to support my feet, which over-pronate (collapsing inward, and stressing the medial meniscus). This apparently was not a problem with narrow Q-factor road bikes, but the slightly added width of the Domane+ exacerbated the situation, especially on the left which is the foot that is the worst..

I have to say I am very happy about this turn of events, as I do love this bike. It is so solid-feeling, and rides well, even without the assist turned on (I sometimes forget, haha).
Click to expand...
I'm glad to know that on one hand, you found the cause of your discomfort, and on the other, that it's a cause that can be appropriately corrected. Without a doubt, getting back on the bike is priceless. Take it easy!
 
Full Discharge, Second Test: As you may recall, the purpose of the first discharge test was to verify the discharge percentage at which the TQ system would cut off during the first deep discharge. The cutoff was confirmed at 5%. Today, in the second deep discharge test, we aim to determine the percentage of discharge at which the system cuts off (TQ says ....the battery management system will “learn” what it needs to know and will deplete all the way to 0% on future rides). This second test confirms that the system cuts off when reaching 0% discharge, thus aligning with the manufacturer's specifications. With this verified data, you can now plan your journeys with accurate final values. Regards.
 
AntonioAlfaro said:
Grinding Noise

What seemed perfect ceased to be so. My odometer has crossed the 1000 km mark, and in the last three rides, a terrifying noise started coming from the TQ50 motor of my 2023 Domane+ SLR. For a moment, I thought some mechanism inside the engine was being ground because it was an abnormal noise I had never heard before. After my initial terror subsided a bit and and thinking about my return home, I began to notice that this deafening noise occurred under certain circumstances, but most of the time or when the motor was in OFF mode, it did not happen. I found that the grinding noise was correlated with my cadence, the power from both me and the motor, and the rear gear ratio. The noise didn't occur when I was climbing a hill, applying power to the pedals. It happens when you're on a flat slope, stop pedaling for a moment, and then start rolling again. When you begin pedaling again, there seems to be a kind of desynchronization between the motor and the pedal axle, and the grinding noise appears. It's as if there are unsuccessful attempts to engage the motor with the transmission axle. During these moments, I observe that I'm delivering some power, I'm over-rotating, and the motor is delivering very little power (no more than about 10W). However, if I shift to a higher gear, reducing rotation and increasing the power delivered by the motor, the noise disappears completely. As long as the motor is delivering enough power (more than 30W, I'd say), the dreadful grinding noise doesn't occur.

Is this an intrinsic characteristic of the TQ50 motor? Is it a design flaw? Is it a software issue with motor control? Is it normal and should one simply avoid the conditions in which it occurs?

I'd like to know if anyone in this forum is experiencing the same noise.
Click to expand...
Did they ever fix this for you?
 
AvalancheRun said:
Did they ever fix this for you?
Click to expand...
Hi AvalancheRun, let me paste parcial answer that I wrote in other forum.:
"" As of today, I have completed 46 rides on the Trek Domane+ SLR, covering a total of 2400 km, approximately 118 hours. Overall, I haven't had any significant issues to climb. I only recall noticing a grinding noise a few months ago, but after updating the firmware, making some minor adjustments to my settings, and understanding the reason for the grinding noise, I can now say it is easily manageable.""
While it is true that with the latest updates released by TQ, the grinding noise improves significantly, it must be clear that this is intrinsic to the engagement and disengagement system of the assistance. The system disengages around 30W more or less, so around this point there is a kind of hysteresis that needs to be quickly overcome to avoid the grinding noise. This can be achieved by delivering more power (cyclist) to the system, which may involve using a stronger gear. The idea is to learn to overcome the hysteresis point, which from another perspective is an indication that we have exhausted the gear and it is time to change gears
 
Antonio, glad to see you are staying involved.

Wondering what TQ update you are alluding to. I'm not aware of any substantive firmware update since January 2023. With another year's experience and more bikes in use, I thought one would have come at around this time, with some beneficial tweaks, not the least of which would be to allow the cyclist to understand what's on the ebike besides a series of numbers. I've been campaigning for an increase maximum assist from 200 to 300% to help riders with limited power (~100W) to tap into the (unchanged) motor's 300W max output. That is not to say that tweaks aimed at even better motor performance wouldn't be welcome and widely appreciated.
 
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