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Discussion Starter #1
I just noticed that the chainring on my E8000 motor appears to be floating, is this normal, as the locknut is tight.
 

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What are you asking about? Is there a problem, such as the chainring able to tilt, move laterally freely, or rotate in a non concentric manner? If so, that's not normal.

If you perhaps mean that you're confused by how the chainring's attached to the motor, instead of spindle or crank, then that's normal. Sorry if this isn't it and my guess insults your intelligence; have to guess when you don't give much context to work off of.
 

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Discussion Starter #3
The chainring has side to side play with the locknut tight. Like a floating brake rotor.


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Discussion Starter #7
Gotcha. You just hand tightened that, I see. Did you try applying 30nm of force on it?

If it's still loose, might just need a spacer to actually apply pressure on the chainring.
The lockring was tight to begin with and the chainring was still loose, that was why I raised the question. The tech docs show no spacer, so it's either designed like this, or its missing a spacer that isn't shown in the tech docs, or it is assembled incorrectly although it seems to work fine.

I was hoping that someone who has an ebike with the Shimano E8000 DU could just check theirs and let me know.
 

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I just took my chainring off last night and all I see behind the chainring is a circlip. I dont see a spacer. There is definitely something wrong there. There is a spacer between the chainring and the crank arm. Sorry I cant be of more help here.
 

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Discussion Starter #10
Can anybody here with a Shimano e8000 drive just verify that their chainrings are tight to the shaft?


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The chainring spider and chainring should not float at all. Mine is tight. I watched your video. That does NOT look correct at all.
 

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I see from the tech docs that there are 2 spiders, perhaps they are different thicknesses and mine was spec'ed incorrectly

https://si.shimano.com/pdfs/ev/EV-FC-E8050-FCE8000-4068C.pdf
Searched those model #s and one set said 50mm chainline, and the other set said 53mm chainline.

https://bike.shimano.com/en-EU/product/component/mtb-ebike-e8000/SM-CRE80.html
https://bike.shimano.com/en-EU/product/component/mtb-ebike-e8000/SM-CRE80-R.html
https://bike.shimano.com/en-EU/product/component/mtb-ebike-e8000/SM-CRE80-B.html

Look at how sellers list the chainring without spider:

https://www.bike-discount.de/en/buy...80-sm-cre80-b-chainring-without-spider-736216

I get the impression that the spider is merely offset by 3mm, to get the chainline optimized based on rear axle spacing (142 vs 148). I expect them to be made interchangeable with the motor, and not have incompatibility like how you speculated.
 

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Searched those model #s and one set said 50mm chainline, and the other set said 53mm chainline.

https://bike.shimano.com/en-EU/product/component/mtb-ebike-e8000/SM-CRE80.html
https://bike.shimano.com/en-EU/product/component/mtb-ebike-e8000/SM-CRE80-R.html
https://bike.shimano.com/en-EU/product/component/mtb-ebike-e8000/SM-CRE80-B.html

Look at how sellers list the chainring without spider:

https://www.bike-discount.de/en/buy...80-sm-cre80-b-chainring-without-spider-736216

I get the impression that the spider is merely offset by 3mm, to get the chainline optimized based on rear axle spacing (142 vs 148). I expect them to be made interchangeable with the motor, and not have incompatibility like how you speculated.
Appreciate that research ninjichor
 

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Discussion Starter #14
Searched those model #s and one set said 50mm chainline, and the other set said 53mm chainline.

https://bike.shimano.com/en-EU/product/component/mtb-ebike-e8000/SM-CRE80.html
https://bike.shimano.com/en-EU/product/component/mtb-ebike-e8000/SM-CRE80-R.html
https://bike.shimano.com/en-EU/product/component/mtb-ebike-e8000/SM-CRE80-B.html

Look at how sellers list the chainring without spider:

https://www.bike-discount.de/en/buy...80-sm-cre80-b-chainring-without-spider-736216

I get the impression that the spider is merely offset by 3mm, to get the chainline optimized based on rear axle spacing (142 vs 148). I expect them to be made interchangeable with the motor, and not have incompatibility like how you speculated.
Thanks for the info ninjichor, it would make sense then that there should be a 3mm spacer on one side of the spider or other depending on chainline. This would also give one motor two chainline options. So I am guessing my motor is missing the spacer, but it is not in the tech docs anywhere. It would be great if somebody could look at their motor and see if there is a spacer on either side and if it is tight to the shaft.
 

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Discussion Starter #15
I just measured the slop, and it’s 0.75mm so it doesn’t seem like a difference in chain line discussion

I’m surprised there aren’t Shimano brand guys all over this forum. I’ve been extracting information from a STEPS field sales tech but his last reco was go to a shop. Bizarre


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Discussion Starter #16
I am also wondering how tight to the snapring that spider should be. It seems like it could pop out and fail without too much force


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