2022 Trek Rail 9.8 Bosch motor cuts out

evilmtb

New Member
Sep 11, 2022
20
2
Bozeman MT
The long and short of it is that the battery mounts in the Rail are very poorly designed.

I had loads of noise from my battery (brand new 9.8) and it did cut out on several occasions going through the trail chunder. I read the new battery alignment procedure but ended up taking the bike back to the shop to be fixed.

the battery alignment document states that you must make sure the plate is flat and not bowed in any direction. This, I think, is still the cause of the issue.

this is how the tech has fixed my rattle and I can report it works and I can also report that the bike no longer powers off. This is not an official Trek fix, but the tech at my local shop is a Trek Rail rider/owner and knows his shit when it comes the Trek bikes.

View attachment 97135 View attachment 97136 View attachment 97137

look how much bow there is in the plate. To me this is a sure sign that the mounts (with a flat plate) are too far apart. I am still using the foam damper on the lower mount.

my battery is now held tight and does not move. Note the thick solid rubber pads that the tech installed to support the rigidity of the top plate.

the battery installs in the same way, but requires a very solid push to get it past the latch and you have to use the key to close the latch down.

i rode over very Rooty trails with this new fix and it held firm with zero issues.

Thanks for the detailed info and images.
It's kind of nuts that we have to hack the bike to get it working properly for the kind of trails this bike is designed and sold for. Oh well.. I like hacking :)

One of the local techs here usually takes that plate out completely and then does the battery alignment. He said he's done it to more than a dozen of these models. I might try your technique first. I'll also find some high density foam with double sticky tape and give that a try above the top plate. The black duct tape on the cables seems to be a good idea as well. Those cable clamps have all pulled away and aren't properly sized to hold the wires anyhow.

Someone with an audience needs to do some durability reviews on this bike and other E-Bikes. This is a great bike, but the durability of the Bosch system clearly needs some work. Bosch's support for riders is really making Trek look bad in my opinion. I wonder if Shimano, Porsche or others is any better.
 

Dave_B

E*POWAH Elite World Champion
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Aug 29, 2020
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from what I can gather, @Mitch@Trek are very aware of the battery issue but will not be fixing it any time soon.

The gaffa tape was my idea, its the only thing I can take credit for, the tech at my LBS did the rest.
 

evilmtb

New Member
Sep 11, 2022
20
2
Bozeman MT
from what I can gather, @Mitch@Trek are very aware of the battery issue but will not be fixing it any time soon.

The gaffa tape was my idea, its the only thing I can take credit for, the tech at my LBS did the rest.

It's fair to say that E-MTB is still in it's early days and there's a lot that needs to get worked out. I still remember riding on elastimer rock shoxs with horse shoe brakes and thinking V-Brakes were the most amazing invention since the bike chain.

If I were the product manager at Trek, Yeti, or elsewhere, I would do whatever I could to support the "Early Adopters". Give them the tools to hack and fix problems with reasonable parameters. Allowing Bosch to lock things down and act like this is a fully baked product is mistake that makes Trek look bad more than Bosch.

Realistically, Trek is in a tough spot. They're not a consumer electronics company. My guess is that Trek is more staffed up and experienced with mechanical engineering. They may have a lot to learn about supporting consumer electronics. In the mean time... happy hacking!
 

Paul Mac

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I feel that in this instance it isn't an electronics issue, it is down to Trek's poor implementation.
There is a 4 kg 1.5 foot lump of metal being held in place by 2 plastic plates, It's never going to work!
There are numerous other ways of securely holding that battery in place, whilst still making it easy to remove.
 

Mikerb

E*POWAH Elite World Champion
May 16, 2019
6,105
4,636
Weymouth
I feel that in this instance it isn't an electronics issue, it is down to Trek's poor implementation.
There is a 4 kg 1.5 foot lump of metal being held in place by 2 plastic plates, It's never going to work!
There are numerous other ways of securely holding that battery in place, whilst still making it easy to remove.
I agree.........as far as I can tell Bosch make the battery and also offer mounting plates. It is up to each bike designer to decide how to fix those in the downtube. The problem of the battery powering off because it is not securely fixed seems to be a Trek problem.......there are loads of other bike brands using the Bosch system without this problem. On one of my bikes the electrical connections are made with an aluminium plug at the bottm of the battery and that is secured by a bolt through the downtube. The top (stopper) plate is also secured by a bolt through the downtube. On my other bike the connection plate is at the top...held by a bolt through the downtube......the battery is held in place by a rail (SIC) system and a clamp type arrangement at the base of the battery.
 

Paul Mac

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I agree.........as far as I can tell Bosch make the battery and also offer mounting plates. It is up to each bike designer to decide how to fix those in the downtube. The problem of the battery powering off because it is not securely fixed seems to be a Trek problem.......there are loads of other bike brands using the Bosch system without this problem. On one of my bikes the electrical connections are made with an aluminium plug at the bottm of the battery and that is secured by a bolt through the downtube. The top (stopper) plate is also secured by a bolt through the downtube. On my other bike the connection plate is at the top...held by a bolt through the downtube......the battery is held in place by a rail (SIC) system and a clamp type arrangement at the base of the battery.
Yes that's what the Trek should have, a compression clamp, like the sort of thing a Soda stream uses to clamp in the bottle, sorry best way of describing I could think of 🤣
 

Onetime

Active member
Aug 10, 2022
367
370
Cali
The cutoff only occurs during a ride and only when I'm riding over heavy chatter.
When it cuts off, I can restart it immediately by powering it back on.
That said, it's super annoying because... You have to wait a few seconds because it powers off gracefully, which takes about 5 seconds. Then you have to start it, which takes a few seconds. Then you have to shift into whatever power mode you want. Normally, you're doing all of this while you're at speed if you want to maintain your momentum.

I don’t have the part number and I can’t find a pic right now, but bosch makes a foam pad that goes on the bottom of the battery mount, where the battery plugs in. This stops all excess movement between the battery and plug when you are riding in the heavy chatter. It also quiets the bike noise from the chatter quite a bit. My Bosch bike, (not a trek) came with it. Since you said that this only occurs when riding heavy chatter, this might be the solution you are looking for. Best part is its only a few dollars too.
 

Onetime

Active member
Aug 10, 2022
367
370
Cali
Here’s a link to the foam pad thread in this forum.

 

Mitchb

Member
Nov 13, 2021
56
41
San Diego
I had shutdown problems on my Yamaha when riding on rough terrain. I first used dense foam pads to reduce battery movement and it helped some but didnt solve the problem. Applying Dielectric Grease to the connections between the battery and motor DID solve the problem; I havent had a shutdown since.

I was told even small movements in the connections cause a carbon buildup which leads to shutdowns. Dielectric grease fixes that.
 

Onetime

Active member
Aug 10, 2022
367
370
Cali
I had shutdown problems on my Yamaha when riding on rough terrain. I first used dense foam pads to reduce battery movement and it helped some but didnt solve the problem. Applying Dielectric Grease to the connections between the battery and motor DID solve the problem; I havent had a shutdown since.

I was told even small movements in the connections cause a carbon buildup which leads to shutdowns. Dielectric grease fixes that.

‘Yeah, I think the combination of the foam pad and dielectric grease will fix this guys shutdown issues. Both cheap easy fixes too.
 

Desert_Turtle

Active member
Mar 1, 2022
120
150
Palmdale, CA
I hate to say this but my feeling is that most of these LBSs just aren’t providing the service that they should. I bought a Mondraker Crafty RR over the summer and the battery went bad the first day I had it (Bosch Smart System 750wh battery). Fly Rides in Hollywood had me make an appointment to look at it. It took a week but when I got there they tested it, said the battery was bad, and swapped it out then and there. They dealt with Bosch. Since the OP brought his bike in and they tested it several times and found a problem it was on the Trek dealer, any Trek dealer, to make sure that the bike was fixed. For others that have battery alignment issues, a Trek dealer, any, should fix that under warranty at no cost. My LBS would.
 

aimage

Member
Jul 8, 2021
26
14
New Zealand
I had the well documented ejecting battery issue occur on my new 2021 Rail 9. Not that they tell you at the time, Trek had developed three different solutions for alignment with the final version sorting the issue for me which was a kit containing a flat metal strip between the battery mounts ensuring they can't move apart. The tell for poor alignment was how easy the key turns for the battery to pop out. Out of the box the key was tight ish to turn and the battery didn't pop out. Had to be pulled on. By 2022 I would have hoped all new Treks would have come with this kit? The New Zealand shop I bought mine from wanted to charge me for the kit and labour but a call to Trek changed that. Not the smoothest warranty process.
 

Bob D

New Member
Sep 25, 2022
3
1
Ontario Canada
Does the LED remote flash orange and cycle down to power off?

I also suspect battery may be faulty here if so…

well they are just taking the piss tell them to fix it all under warranty trek made it they sold it and want you to not only pay for the part and there labour to fit it becouse of there fuck up.

"We've had to do battery alignments for more than a dozen trek rails.

fix it for free or give me my money back or see you in court and cost them a fortune ;)

That happened to both my friend who also owns the and me. We both ride the 9.8 AXS. We found that we could slide the battery up and down when it was in the frame sort of imitating the chop that would influence that same characteristic. When we slid the battery upwards towards the fork tube, the power cut out. We then had to press the power button to restart the system. After several attempts ending up with the same result we decided to place a piece of rubber with an adhesive back at the top of the battery to prevent it from sliding up and disconnecting. Since we made that simple modification neither one of us has experienced the problem

Rail Battery Shim.jpg
 

JP-NZ

Well-known member
Feb 17, 2022
998
754
Christchurch - New Zealand
Owner of 22 9.8XT, FWIW I have had no issues with motor shutoff or battery noise. My rail has the steel bar between the battery mounting ends. I did add a foam damper pad even though I didn't have bad battery noise. Currently 198km on the bike.

BBD06AEC-EA53-46B5-89B0-DDA8C5280412.jpeg
 

evilmtb

New Member
Sep 11, 2022
20
2
Bozeman MT
Owner of 22 9.8XT, FWIW I have had no issues with motor shutoff or battery noise. My rail has the steel bar between the battery mounting ends. I did add a foam damper pad even though I didn't have bad battery noise. Currently 198km on the bike.

View attachment 98091
Mine is a 22 9.8 GX AXS. Same bar. I think the problem started closer to the 300 mile mark.
 

Bob D

New Member
Sep 25, 2022
3
1
Ontario Canada
Mine is a 22 9.8 GX AXS. Same bar. I think the problem started closer to the 300 mile mark.
My Friend's 22 9.8 GX AXS motor cut out started earlier than mine did. His had about 200 km's on it when it started and that was when we noticed the battery movement within the downtube. The rubber shims at the top of the battery resolved the cut out on both of our bikes. Both of the bikes have that bar
 

Mikerb

E*POWAH Elite World Champion
May 16, 2019
6,105
4,636
Weymouth
My Friend's 22 9.8 GX AXS motor cut out started earlier than mine did. His had about 200 km's on it when it started and that was when we noticed the battery movement within the downtube. The rubber shims at the top of the battery resolved the cut out on both of our bikes. Both of the bikes have that bar
.........a foam pad will compress overtime........... a robust hard rubber should maintain its thickness . The foam pad has been around for years. My 2020 Whyte E180 (Bosch Gen 4) has one fitted as standard but it is not there to provide a tight fit. It is just to provide a softer interface between the battery and electrical connector.
 

evilmtb

New Member
Sep 11, 2022
20
2
Bozeman MT
My Friend's 22 9.8 GX AXS motor cut out started earlier than mine did. His had about 200 km's on it when it started and that was when we noticed the battery movement within the downtube. The rubber shims at the top of the battery resolved the cut out on both of our bikes. Both of the bikes have that bar

I would be curious to know if the pins in the female end of the battery on the bottom have bent in. If you look in the plug, the contacts are supposed to protrude out to the center. On my battery, they have bent flat and are now barely visible.

With my bike, the vertical movement and extra vibration was the first problem that created this second problem. My guess is that you're battery pins have compressed in as well.
 

Bob D

New Member
Sep 25, 2022
3
1
Ontario Canada
I would be curious to know if the pins in the female end of the battery on the bottom have bent in. If you look in the plug, the contacts are supposed to protrude out to the center. On my battery, they have bent flat and are now barely visible.

With my bike, the vertical movement and extra vibration was the first problem that created this second problem. My guess is that you're battery pins have compressed in as well.
Just checked and the contacts all appear to be fine . I have had no shut off issues since I placed the rubber shims at the top of the battery
 

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