Anyone else with a rail Carbon frame notice this..

Richiefromboston

Active member
Mar 15, 2021
228
121
Boston, Ma. USA
JUst swapped out carbon wheels, and whilst test riding in backyard notice the chianstay was moving a bit while pedaling, then I notice the entire bosch motor was too. not massively but not rock solid. Not sure if its always done this but I dont believe so.
 

Richiefromboston

Active member
Mar 15, 2021
228
121
Boston, Ma. USA
Ok I found the issue, and Im glad I noticed it. the 4 small tamper proof bolts tow simply sheared off. So I was able to remove them But now I have to figure out the exact size or find the trek part number. Its simply amazing I literally just posted here today how I havent had and reliability issues with my not even a year old 500 miles on it rail and this happens same day. strange right. anyone know either part number for mounting bolts or the size pitch of bolts?

Screenshot 2021-11-25 at 15-59-30 Trek Rail 9 7 Motor Mount Part Number - EMTB Forums.png
 

Richiefromboston

Active member
Mar 15, 2021
228
121
Boston, Ma. USA
But not compensatory pies, definitely not more pies ! Jeez Richie, how hard were you riding it in the dark ??????
I hit trek up on instagram( had good luck there b4) But now I cant ride it. I just want to figure out size get put them in and roll. Im looking up any TS25 5 point star tamper proof button heads I can get here fast. Im just not sure on the size.
 

Richiefromboston

Active member
Mar 15, 2021
228
121
Boston, Ma. USA
There is a Trek contact on the forum, but I can't remember their username !!!! :confused:
No worries Im on it( I think) just sucks was on road for 4.5months been home almost 2 weeks need to get myslef physically ready to roll out again and that what the rail is for, and sadly shes down for now. Luckily I noticed the prob or it would have been bad out in the forest at night, alone, scared and hungry( no pies) you get the point lol all I need is bolt size and Ill be fine. Im not abig bring it to the dealer guy.
 

Slapbassmunky

Active member
Aug 1, 2020
282
292
Isle of wight
I had a creak I couldn't get rid of. Found out it was those bolts. I can't remember the exact size, but it's a standard metric thread probably M5 it wasn't anything special because I replaced them with some off the shelf ones I already had in the shed.

The torque value is very low for these fixings and my motor mount plates were really badly aligned, I shimmed the plates with a washer or two to get the whole assembly to drop into the frame nicely and torqued the fixings up to something I deemed more appropriate. You can't access them with the motor in the frame, so you have to gently nip them up and do trial and error fitment before cranking them up properly.

Since doing this I haven't had any creaks or clicks from the bike, it's been silent. Utterly appalling QC from trek. The screws are supplied with the motor, I have a hunch trek receive the assembly from Bosch and should line up the mounts before removing again and torquing properly, but they don't.
 

Mitch@Trek

Official Trek
TREK
Dec 30, 2020
44
111
Waterloo, WI
I hit trek up on instagram( had good luck there b4) But now I cant ride it. I just want to figure out size get put them in and roll. Im looking up any TS25 5 point star tamper proof button heads I can get here fast. Im just not sure on the size.

Hey Richie, I have bad news. I'm chatting with our internal Bosch expert to see if we can find part specs for those fasteners. Unfortunately, Bosch has that information under wraps and these are not even listed as a serviceable part for the plates/fasteners*. They supply them already installed on the drive unit. Bosch suggests not to remove/replace them since they are self-tapping and if cross-threaded, you'd need a new drive unit.

I would recommend submitting a warranty claim to Bosch as they will likely send you a new drive unit to replace this one. You can submit a claim through any Trek dealer, not just the one you purchased the bike through.

*Also, just for any onlooker reference, the fasteners in discussion (highlighted) have a torque spec of 8 Nm and Bosch suggests using Loctite 290 on them - but again, not to fully remove due to being self-tapping screws.

1638288645602.png
 
Last edited:

Mitch@Trek

Official Trek
TREK
Dec 30, 2020
44
111
Waterloo, WI
Utterly appalling QC from trek. The screws are supplied with the motor, I have a hunch trek receive the assembly from Bosch and should line up the mounts before removing again and torquing properly, but they don't.

These fasteners are installed and made by Bosch. We don't make the motor or retaining plates - we just install them into the frame.
 

Zimmerframe

MUPPET
Subscriber
Jun 12, 2019
13,954
20,691
Brittany, France
Hey Richie, I have bad news. I'm chatting with our internal Bosch expert to see if we can find part specs for those fasteners. Unfortunately, Bosch has that information under wraps and these are not even listed as a serviceable part for the plates/fasteners*. They supply them already installed on the drive unit. Bosch suggests not to remove/replace them since they are self-tapping and if cross-threaded, you'd need a new drive unit.

I would recommend submitting a warranty claim to Bosch as they will likely send you a new drive unit to replace this one. You can submit a claim through any Trek dealer, not just the one you purchased the bike through.

*Also, just for any onlooker reference, the fasteners in discussion (highlighted) have a torque spec of 8 Nm and Bosch suggests using Loctite 290 on them - but again, not to fully remove due to being self-tapping screws.

View attachment 77152
10/10 for the information ! Go TREK !
 

Slapbassmunky

Active member
Aug 1, 2020
282
292
Isle of wight
These fasteners are installed and made by Bosch. We don't make the motor or retaining plates - we just install them into the frame.
Hi Mitch, I knew that anyway. The issue is TREK should check them before installation, it's your reputation on the line after all.

On my 9.8XT one of the M8 motor mount/frame bolts had been installed cross threaded (it looked perfectly straight from the front), which must have taken some real gusto to do, because one of the motor mount plates didn't line up properly. I had to remove everything and fix this first with a rivnut before finding out the creaking noise was actually these 8 bosch screws backing off. The plates were loose....

All this at 4 months old.

If it was a £6800 motorcycle I'd have gone back to the dealer extremely upset that a major component wasn't fixed/torqued to the bike properly. But hey, when the dealer is 150 miles away, you fix it yourself. I know this sounds like a massive rant, I'm not trying to have a go at anyone, but those are the facts.
 

Huw169

New Member
Nov 7, 2021
39
20
Hampshire
Hi guys. Are these plates on all Bosch motors, or just on the ones that go into the Trek frame? I need to take a look at mine when I get a mo.
Good info on this thread though, so cheers. And hope those with issues can get back in the saddle soon 👍
 

Zimmerframe

MUPPET
Subscriber
Jun 12, 2019
13,954
20,691
Brittany, France
Hi guys. Are these plates on all Bosch motors, or just on the ones that go into the Trek frame? I need to take a look at mine when I get a mo.
Good info on this thread though, so cheers. And hope those with issues can get back in the saddle soon 👍
Not all, but also, not just Trek's. Seems to be one mounting option they offer.
 

Paul Mac

E*POWAH Elite World Champion
Patreon
Subscriber
Jul 9, 2018
997
1,046
Uk
These bolts also failed on my Rail, ended up with a new motor.
I was disappointed to see that the exact same bolts and mounting plates are on the new motor, so I know they will eventually fail again.
 

Slapbassmunky

Active member
Aug 1, 2020
282
292
Isle of wight
These bolts also failed on my Rail, ended up with a new motor.
I was disappointed to see that the exact same bolts and mounting plates are on the new motor, so I know they will eventually fail again.
Remove the motor and check everything's aligned properly. If it is, remove one screw from each plate at a time, apply blue loctite, and torque up nice and tight.

This is what I did and I haven't had a problem since.
 

folmonty

Active member
Mar 11, 2021
151
153
NorCal
Sounds like a little shop time is in order. Is this just for carbon frame bikes or ALU also? Need to get in and give a once over anyway. eMTB's are definitely more maintenance intensive but IMO the fun factor is worth it. Sorry for @Richiefromboston troubles! Shit, reading through the different brands is no different with any of them. This tech is developing and changing constantly. In another 5 years we'll all be laughing at where we'd been!
 

slomtbr

Active member
Subscriber
May 14, 2021
128
98
US
Sounds like a little shop time is in order. Is this just for carbon frame bikes or ALU also? Need to get in and give a once over anyway. eMTB's are definitely more maintenance intensive but IMO the fun factor is worth it. Sorry for @Richiefromboston troubles! Shit, reading through the different brands is no different with any of them. This tech is developing and changing constantly. In another 5 years we'll all be laughing at where we'd been!
The alloy Rails have the same motor mounts.
 

Sean0711

Member
Nov 30, 2020
45
24
Surrey, uk
these bolts worked their way loose on my 9.8xt about 5 months after I got it, Ive had it just over a year done about 700 miles and it looks lke they have done the same thing again! the give away is when the motor moves enough for the chainring to skim into the chain stay! cuts quite a nice groove... will be getting back to trek once the holidays are over to see what they do next!
 

Paul Mac

E*POWAH Elite World Champion
Patreon
Subscriber
Jul 9, 2018
997
1,046
Uk
The problem is, it's not just the bolts coming loose.
They actually wear the alloy brackets holes oval, so that no matter how tight the bolts are the motor still moves.
 

Doomanic

🛠️Wrecker🛠️
Patreon
Founding Member
Jan 21, 2018
8,643
10,256
UK
Is this issue limited to carbon Rails or are Ally Rails affected as well?
 

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