At Least ****** Has the Tools I Need

slomtbr

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May 14, 2021
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2021 Rail 7 after 20 miles.
I checked the torque of every other fastener…
 

GrahamPaul

E*POWAH Elite World Champion
Nov 6, 2019
1,127
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Andalucía
I'm a bit confused there. Do you normally check the torque on fasteners by undoing them? The Bosch spider locknut ring is a reverse (left hand) thread, so you tested it by undoing it.

It's only torqued to 25Nm against a rubber O-ring, so it's easy to undo (mine are Locktited in place).
 

slomtbr

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I wasn't checking it; it came loose on the second ride.
Now come the tools, safety wire and the fix.
 

1981Miked

Active member
Jun 14, 2020
94
118
Dundee
Mine did the same after a few rides, i just tightened it up and carried on enjoying the bike. No issues since and I check it regularly.
 

slomtbr

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May 14, 2021
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25-30 Nm is stamped on my lockring, (2021 Rail 7)
1621971522224.png


1621446757703.png
 
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slomtbr

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May 14, 2021
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Corrected: I had everything but the 36mm crow foot to go on the Park BBT-18 (it's on order), so I used about 2 US gallons of water pulling down on a wrench 1 foot from the spindle :)

IMG_2223.jpeg
 
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GrahamPaul

E*POWAH Elite World Champion
Nov 6, 2019
1,127
1,088
Andalucía
So 30ftlbs. Not sure what a g/ft is.

32 ft lbs, which gives a torque of 44Nm. Which is around 50% above the maximum quoted torque. I understand that this directly tightens the motor bearings, which is why Bosch quote a low maximum value...
 
Last edited:

slomtbr

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May 14, 2021
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32 ft lbs, which gives a torque of 44Nm. Which is around 50% above the maximum quoted torque. I understand that this directly tightens the motor bearings, which is why Bosch quote a low maximum value...
Thank you - I did the conversion backward - more work tonight. I'm glad I didn't ride it.
 

slomtbr

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May 14, 2021
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Imperial gallon weighs 10lbs, by your figures 4 US gallons weigh 30lbs. So 30 ftlbs
US gallon weighs 8.3lb., so I corrected my work using 2 US gallons for about 16.6 ft-lb.
 
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BeBiker

Active member
Aug 26, 2020
694
415
Belgium
In other applications, I saw this lock washer to secure a toothed lock ring.

trailer tang washer 15 - 24101d.jpg
08-500x500.jpg

Could this be a solution ?
 
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Is this a Trek specific problem with its lockring loosening over time? On both my bosch cx powered bikes, I have not experienced this. Although I did paint a small marker (white line) across lockring nut and spider to detect any loosening. Checking before each ride. Didn't notice anything yet.
 
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Paulquattro

E*POWAH Elite
May 7, 2020
2,202
1,215
The Darkside
Is this a Trek specific problem with its lockring loosening over time? On both my bosch cx powered bikes, I have not experienced this. Although I did paint a small marker (white line) across lockring nut and spider to detect any loosening. Checking before each ride. Didn't notice anything yet.
Hi
No its Bosch specific
Im on my 3rd bike with the motor and just throw away the o rings and loctite the nut
3k in and no loose lock nut (y)
 

Expidia

Well-known member
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Jun 27, 2022
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Capital Region, New York
Is this a Trek specific problem with its lockring loosening over time? On both my bosch cx powered bikes, I have not experienced this. Although I did paint a small marker (white line) across lockring nut and spider to detect any loosening. Checking before each ride. Didn't notice anything yet.
Great idea on the marker. I would have never thought of doing that.
 

Stihldog

Handheld Power Tool
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Jun 10, 2020
3,361
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Coquitlam, BC
Hi
No its Bosch specific
Im on my 3rd bike with the motor and just throw away the o rings and loctite the nut
3k in and no loose lock nut (y)
Yeah, I always wondered about that o ring? Do you remember if it was brass, plastic or rubber?

I replaced the original chainring with an ethirteen 34t. However on the back of the new ethirteen chainring an area extends out seemingly to replace a metal o ring. If I left the metal o ring in place the new ethirteen chainring would extend too far out and chain alignment would be wrong.

So I made a decision to reassemble everything without the metal o ring. I could have used blue lock tight on the castle nut but if needed. I torqued the nut to spec and I’ve had no loosening issues in the past year.
I had no reassemble manual for the ethirteen chainring, but without the original o ring(metal/brass ?) the chain alignment and castle nut fit was perfect.
IMG_6181.jpeg

Note how the new ethirteen chainring protrudes slightly on the backside. (I keep a spare).

Also pictured are two types of castle nut sockets. One works fine with a 1/2” torque wrench and the other needs an adjustable wrench or a specific sized socket or crow-foot. However, most of my maintenance/work is done while the bike is in the work stand and since the bike wobbles around the castle nut socket can slip off. Not to big a deal …but?

My point is. I’ve once seen a picture of a castle nut socket that has an alignment bolt which secures and holds the socket in place. But I can’t find it again, and no one knows what I’m talking about. Any ideas?

Anyways, a little blue lock tight around the threads of this nut won’t hurt …but fortunately I haven’t needed any.
 

Paulquattro

E*POWAH Elite
May 7, 2020
2,202
1,215
The Darkside
Yeah, I always wondered about that o ring? Do you remember if it was brass, plastic or rubber?

I replaced the original chainring with an ethirteen 34t. However on the back of the new ethirteen chainring an area extends out seemingly to replace a metal o ring. If I left the metal o ring in place the new ethirteen chainring would extend too far out and chain alignment would be wrong.

So I made a decision to reassemble everything without the metal o ring. I could have used blue lock tight on the castle nut but if needed. I torqued the nut to spec and I’ve had no loosening issues in the past year.
I had no reassemble manual for the ethirteen chainring, but without the original o ring(metal/brass ?) the chain alignment and castle nut fit was perfect.
View attachment 112518
Note how the new ethirteen chainring protrudes slightly on the backside. (I keep a spare).

Also pictured are two types of castle nut sockets. One works fine with a 1/2” torque wrench and the other needs an adjustable wrench or a specific sized socket or crow-foot. However, most of my maintenance/work is done while the bike is in the work stand and since the bike wobbles around the castle nut socket can slip off. Not to big a deal …but?

My point is. I’ve once seen a picture of a castle nut socket that has an alignment bolt which secures and holds the socket in place. But I can’t find it again, and no one knows what I’m talking about. Any ideas?

Anyways, a little blue lock tight around the threads of this nut won’t hurt …but fortunately I haven’t needed any.
The O, ring was rubber on mine
I have a direct mount sprocket as well and use nothing behind it just directly mounted to the motor with the nut.
 

Stihldog

Handheld Power Tool
Subscriber
Jun 10, 2020
3,361
4,655
Coquitlam, BC
The O, ring was rubber on mine
I have a direct mount sprocket as well and use nothing behind it just directly mounted to the motor with the nut.
Ok, now I remember. The o ring on mine was more like a metal spacer. With the new ethirteen chainring the metal o ring wasn’t needed or possible for correct alignment. There was however a blue rubber o ring which I left in place.
The entire assembly seemed kinda strange to me but it’s been working just fine for a long time. In the pic you can see two plastic o rings (very thin) that I didn’t install. Maybe these needed to go between the blue rubber o ring and new ethirteen chainring. Hmmm 🤔. I might have screwed up.…but the nut doesn’t come loose.
 

Paulquattro

E*POWAH Elite
May 7, 2020
2,202
1,215
The Darkside
Ok, now I remember. The o ring on mine was more like a metal spacer. With the new ethirteen chainring the metal o ring wasn’t needed or possible for correct alignment. There was however a blue rubber o ring which I left in place.
The entire assembly seemed kinda strange to me but it’s been working just fine for a long time. In the pic you can see two plastic o rings (very thin) that I didn’t install. Maybe these needed to go between the blue rubber o ring and new ethirteen chainring. Hmmm 🤔. I might have screwed up.…but the nut doesn’t come loose.
Don't fix it what isn't broke , as the saying goes (y)
 

Ark

Active member
Mar 8, 2023
450
368
Newcastle Upon Tyne
Is this a Trek specific problem with its lockring loosening over time? On both my bosch cx powered bikes, I have not experienced this
It's a well known issue on rails, as is the bikes coming with a rear derailleur bolt not torqued to spec and the deraileur whacking into the frames after a few rides, destoying the frame if it was a carbon one.
I was considering a rail7 but everything I read about them put me off them, I ended up going with a Whyte E-160s 29er instead and I've done 185 miles with no lockring issues, no Bosch issues at all and everything working as intended thus far.

If you buy a rail it seem sit's mandatory to buy the Bosch gen 4 lockring tool a crank extractor and a torque wrench, although everyone probably has a torque wrench anyway.
 

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