Creaking/clicking from motor area

My experience: Had to remove the motor for dropper service. There's thin paperlike gaskets between the motor and frame contact points. Took two of them away because they were a bit wrinkled. I also put just a little grease for the contact points as I thought that the assembly would go little easier.

The bike made squeaky noises for the first ride. I retightened the T40 torx, but they were ok.

Since the first ride after service there has been no sound. The sound always came when I pushed the pedals. I think I'll have to replace the gasketlike papers for the mounting points as they might act as some kind of shimplates (who knows).
 
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Interesting that when I removed my motor there were no gaskets between the mounting plates and the frame, however I did exactly that and added some copper slip to give it some movement without rubbing. Will need to do a long ride to see if it's gone. It's way way too muddy at the moment to bother with the cleaning and wear and tear on the drive train. Hopefully the next week or so will allow the ground to dry out just a bit !
 
Also it's pretty clear 20nm is not very tight for this motor mount bolts, all the load and weight of the rider moving left and right together with the twisting forces of the cranks and motor go though those bolts, I am not surprised they creak with tiny amounts of movement. I can see why they used to put paper gaskets in there. Seems strange they stopped. Anyway, the bolts are not big so you can't really go above 20nm but I am not really surprised there is tiny movement there. Maybe there is meant to be by design, but the noise is a unfortunate by product !
 
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ddbros said:
My creak in the main pivot only showed up when I put pressure on the pedals, it wasn't there when I just pushed on the seat. It seems like putting force through the pedals makes the creak more likely to show itself. Oiling the pivots one time resolved it. I should probably take it apart this winter and clean/re-grease it.

I also had a little rattle from the battery. I put a piece of high density foam on the inside of the frame to put some added pressure on the latch. I have to put a little extra effort in to get it latched now, but the rattle is gone.
Click to expand...

Well I have another creak, but like yours it went away after I washed the bike !, Wasn't able to isolate which pivot or area was causing the creak, prob should have been more scientific about cleaning it. Whatever was causing it water stopped it, which makes me things it's not the motor mount bolts this time..... Will need to look into it. Did you just use oil or something like a PTFE spray etc ?
 
Link said:
Also it's pretty clear 20nm is not very tight for this motor mount bolts, all the load and weight of the rider moving left and right together with the twisting forces of the cranks and motor go though those bolts, I am not surprised they creak with tiny amounts of movement. I can see why they used to put paper gaskets in there. Seems strange they stopped. Anyway, the bolts are not big so you can't really go above 20nm but I am not really surprised there is tiny movement there. Maybe there is meant to be by design, but the noise is a unfortunate by product !
Click to expand...

Joined this forum to discuss this issue! My two-month-old Rail 9.8 developed a very similar creaking sound from the motor area, but so far I haven't managed to solve it.

I was able to isolate it to one bolt, the left rear motor mount (T40 Torx-Plus): if I loosen that bolt, the creaking sound goes away, but if I tighten it up, the creaking returns.

After torqueing all six motor mount bolts to 20Nm, the creaking sound remained.

So yesterday I removed all six bolts and the crash guard, and dropped the motor enough to get to the inner 5-pt-star security bolts that attach the mounting plates to the motor. But unfortunately, all of them were very tight already, so that wasn't the source of my creaking sound. I might add that I did have to unplug a couple motor wires to get the motor to slide out; there wasn't enough play in the cables otherwise.

So now I'm not sure what my next step is. I didn't see any gaskets, paper or otherwise, between the frame and the motor mount tabs. Should there be something there?

There was a bit of gap between the frame and the mounts, so I'm thinking about trying to slide in a very thin washer (teflon?) to let it slide a bit without creaking. But I'm not entirely sure I ought to be encouraging movement at all.

The LBS where I bought the bike hasn't been helpful so far (they didn't know the proper torque values for the motor bolts, and so far haven't been able to get that information, so I called Trek myself and got it without trouble).

Any further updates or suggestions from fellow creaky-motor-owners?

Also, to contribute something to the discussion, I learned these things so far in my journey:
  • The six exterior motor mount bolts are Torx-Plus, not regular Torx. I had to order a set of Torx-Plus bits to work on it properly.
  • The Bosch motor mount plate uses "Tamperproof Torx Plus 5 Point Star" bolts. I got a set of these bits made by Neiko that work well.
  • And for my Rail 9.8 at least, the proper torque for the motor mount bolts is 20Nm, as discussed above.
 
seabeast said:
Joined this forum to discuss this issue! My two-month-old Rail 9.8 developed a very similar creaking sound from the motor area, but so far I haven't managed to solve it.

I was able to isolate it to one bolt, the left rear motor mount (T40 Torx-Plus): if I loosen that bolt, the creaking sound goes away, but if I tighten it up, the creaking returns.
Click to expand...

Wanted to follow up with how my problem was solved: long story short, it was the inside motor mount bolts. I took it to my bike shop, and after checking many other potential noise sources, they finally removed and reinstalled the motor. That did it! I've taken it on exactly one significant ride since picking it up, and the annoying creaking sounds are now gone.

The longer version is that despite telling the LBS service people my diagnostic results described above, e.g. that I found a single motor mount bolt that seemed to control the noise, they test rode it and concluded the noise was coming from the main pivot of the rear suspension triangle. The shop cleaned and lubed all parts of the suspension, retorqued the bolts, etc., and even exchanged messages with Trek about the problem. Trek suggested more suspension-related things to check, but the sounds persisted.

I asked the tech again about the motor mounts, and if he'd been able to reproduce my result with the one mount bolt. The next day I got a message saying he'd removed and reinstalled the motor and the sound was gone. Oh well, all's well that ends well, I guess.
 
JMD said:
Yup,
Take off bash guard
Remove 6 TX40 bolts
Lift up motor, no need to unplug any wiring
1 of the aluminium plates was loose, I could move the screws with my fingers.
Luckily I caught it before it damaged the plate severely.
& A dab of paint on all 8 bolt heads to see at a glance if bolts move again
Click to expand...
@JDM any idea what size those tamper proof bolts are holding the 59 plate on? I just pulled mine apart before heading off for my nightly ride and 2 were simply sheared off I want to replace them all just not sure on size. Thanks
 
I just checked mine. They are super tight from the factory for me.
motor_mount.jpg
 
I don’t understand why Trek or Bosch didn’t issue a recall, or at least a bulletin regarding this issue. Ignoring this sound can be costly and Trek or Bosch can easily discredit a warranty claim by sitighting “operator abuse “.

The results can be strange creaking noises, sheared or loose bracket bolts, a cracked frame. (Motor mount insert area). Removing a sheared bracket bolt from the motor casing is almost impossible and can result in a new motor …at your expense.

Chasing the creak, the squeak, or cracking noise can be puzzling. Don’t be fooled into thinking that it could be the motor mount bolts (6), a loose crank, a worn pedal, headset bearings, pivot bolt, suspension components etc. (all those things should be regularly serviced anyway).

The only way, or time, that the noise is usually heard, is during applied torque in real-world conditions. Rarely can it be detected when your bike is suspended, flexing the crank or turning the motor.

If this noise or sound magically goes away …now you’ve got a serious problem.

Drop the motor, check the motor mount bolts (6), check the bracket mount bolts (8). Apply a small amount of blue lock-tight to all those bolts. Don’t apply any grease on or near these bolts …they are not supposed to move …period. If these bolts are allowed to slip or move …you could have a problem.
 
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