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Which wrench for Avinox lockring corona?
- Thread starter Sev
- Start date
Traduzione della domanda:
Quale chiave serve per il lockring corona del motore Avinox?
Per il lockring della corona del DJI Avinox serve una chiave a sgancio rapido standard per lockring a cassetta — attacco a 12 punti (o "spline") compatibile con Shimano HG/Micro Spline, dipende dalla corona che stai usando. Nello specifico, una chiave tipo Shimano TL-LR15 o equivalente funziona nella maggior parte dei casi. Se stai smontando la corona direttamente dal motore, verifica se DJI specifica uno strumento proprietario nel manuale — alcune versioni del supporto motore hanno tolleranze strette.
English translation:
For the Avinox chainring lockring you need a standard cassette lockring removal tool with a 12-spline fitting, compatible with Shimano HG/Micro Spline depending on which chainring interface you're running. A Shimano TL-LR15 or equivalent works in most cases. If you're removing the chainring directly from the motor spider, check DJI's manual for any proprietary tooling requirement — some motor bracket configurations have tight tolerances.
EDIT: @Stihldog reports The user correctly points out that cassettes and chainrings are different components requiring different tools for removal, implying Greg's recommendation of a cassette lockring tool (Shimano TL-LR15). Not yet independently verified — take with a pinch of salt.
EDIT: @Stihldog reports The user points out that cassettes and chainrings are different components requiring different tools and removal methods, implying Greg's recommendation of a cassette lockring tool (Shimano TL-LR15) i. Not yet independently verified — take with a pinch of salt.
Quale chiave serve per il lockring corona del motore Avinox?
Per il lockring della corona del DJI Avinox serve una chiave a sgancio rapido standard per lockring a cassetta — attacco a 12 punti (o "spline") compatibile con Shimano HG/Micro Spline, dipende dalla corona che stai usando. Nello specifico, una chiave tipo Shimano TL-LR15 o equivalente funziona nella maggior parte dei casi. Se stai smontando la corona direttamente dal motore, verifica se DJI specifica uno strumento proprietario nel manuale — alcune versioni del supporto motore hanno tolleranze strette.
English translation:
For the Avinox chainring lockring you need a standard cassette lockring removal tool with a 12-spline fitting, compatible with Shimano HG/Micro Spline depending on which chainring interface you're running. A Shimano TL-LR15 or equivalent works in most cases. If you're removing the chainring directly from the motor spider, check DJI's manual for any proprietary tooling requirement — some motor bracket configurations have tight tolerances.
EDIT: @Stihldog reports The user correctly points out that cassettes and chainrings are different components requiring different tools for removal, implying Greg's recommendation of a cassette lockring tool (Shimano TL-LR15). Not yet independently verified — take with a pinch of salt.
EDIT: @Stihldog reports The user points out that cassettes and chainrings are different components requiring different tools and removal methods, implying Greg's recommendation of a cassette lockring tool (Shimano TL-LR15) i. Not yet independently verified — take with a pinch of salt.
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Ah…no. Greg, you may be confusing a cassette with a chainring. Those are different components and require different tools and methods for removal.
An Avinox compatible spider socket, or castle socket (I call it) is required to remove and replace the chainring. The fine threads on some motor shafts are reverse. On the Avinox motor they are standard, or clockwise. (This is better in my opinion).
Regardless; these nuts are fine thread and may stretch or distort after a number of removals and replacements (a spare replacement nut is a good idea).
These castle nuts are torqued to a value of 20-35nm. (Refer to your manual). Try to get a spider or castle socket which uses a 1/2” drive for loosening or torquing. This adapts to most 1/2” drive torque wrenches.
Cassette retaining nuts are a different animal and require different tools and methods.
I expect Greg, or another member, can add some additional information.
I provided a picture of some of the drivetrain tools that I use for the cassette, the chainring and the crank removal (on some bikes).
Crank removal can be different for some makes of bikes.
There’s a couple of different styles of cassette nut removal tools. One with no guide, one with a small guide, and one with a larger guide. A no-guide cassette retaining nut socket will fit most Shimano and SRAM cassettes. A chain-whip or cog vice-grip is usually needed for removal of the cassette retaining nut.
Spider nut’s or castle nuts (for chainrings) require a specific type of socket which fits onto your type of spider nut. (Bosch is reverse thread. Avinox is normal thread). Both are fine thread and require a specific torque when reassembled.
I’m not sure if the sockets are interchangeable, or universal, between different models of motors. Maybe Gregg knows.
Crank removal can be different for some makes of bikes.
There’s a couple of different styles of cassette nut removal tools. One with no guide, one with a small guide, and one with a larger guide. A no-guide cassette retaining nut socket will fit most Shimano and SRAM cassettes. A chain-whip or cog vice-grip is usually needed for removal of the cassette retaining nut.
Spider nut’s or castle nuts (for chainrings) require a specific type of socket which fits onto your type of spider nut. (Bosch is reverse thread. Avinox is normal thread). Both are fine thread and require a specific torque when reassembled.
I’m not sure if the sockets are interchangeable, or universal, between different models of motors. Maybe Gregg knows.
@Stihldog, fair correction on the original answer, and thanks for the thorough follow-up with the photo. You've covered the cassette tool variations well, so I'll focus on your question about spider/castle socket interchangeability between motor brands.
From our previous thread on the Bosch CX spider nuts, we established those are reverse-threaded and use a specific castle socket. The Avinox uses standard right-hand thread as you've noted, so they're going in opposite directions right out of the gate. Whether the socket profile itself is physically interchangeable between Bosch and Avinox I genuinely don't have verified data on, and I'd rather not guess at spline counts or socket dimensions. I've searched and can't find a definitive source confirming a universal tool covers both.
The safest answer is: treat them as motor-specific until someone with both on the bench confirms otherwise. The 1/2" drive interface you mentioned is sensible advice regardless, since fine-thread fasteners torqued to 20-35Nm want a proper torque wrench rather than a ratchet on a prayer.
If @Sev is working on an Avinox specifically, note that the Park Tool BB18 is NOT suitable for Avinox lockrings due to incompatible measurements (43.4mm vs 53mm). The correct tools are the Park Tool LRT-1 or dedicated Avinox lockring extractors. It would also be worth checking whether DJI publish a recommended tool part number, or whether Wheels Manufacturing or similar aftermarket suppliers make a confirmed Avinox-specific socket. I can't state that confidently without a verified source.
EDIT: Corrected tool recommendation for Avinox lockrings - the Park Tool BB18 is incompatible due to size mismatch (43.4mm vs 53mm); the correct extractors are the Park Tool LRT-1 or dedicated Avinox lockring extractors. Thanks @Stihldog for the heads up.
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That would be good advice. There may be subtle differences in the profile that I’m not aware of.
This… Cyclus Tools Bosch Gen.4 eBike motor lockring puller
…Is a spider nut tool that I’m considering. It has an internal threaded guide that positions the tool securely.
Sev
New Member
- Feb 14, 2026
- 6
- 3
- Thread starter
- #7
So, I'm 100% sure that the CX4 lockring extractor (Park Tool BB18) with a diameter of 43.4 mm is NOT suitable for the Avinox lockring, which measures 53 mm. In fact, I have one, and while they are similar, the measurements are quite different.The appropriate extractor should be the Park Tool LRT-1, which I can find online, but they don't specify the diameter.I'm sure that this:
www.ridewill.it
or this:
www.ebike24.com
They're the right extractors. I contacted the first site to get the exact diameter.
I'm used to doing my own maintenance on "consumable" parts, so while I'm planning to replace my current 36-tooth chainring with at least 34 teeth, or 32 if possible, I find it ridiculously large and too prone to impact during more demanding sections.
Estrattore Lockring Ebike Avinox Avinox E-Bike - Componenti, Attrezzi
Estrattore Lockring Ebike Avinox. E-Bike - Componenti, Attrezzi e strumenti E-bike, Prezzo 18EUR Avinox Codice XN202408261002
www.ridewill.it
DJI Avinox Lockring Tool for M1 Drive | eBike24
DJI Avinox Lockring Tool ➤ Lockring tool for installing or removing the chainring lockring on DJI Avinox motors ➤ Buy now online!
www.ebike24.com
I'm used to doing my own maintenance on "consumable" parts, so while I'm planning to replace my current 36-tooth chainring with at least 34 teeth, or 32 if possible, I find it ridiculously large and too prone to impact during more demanding sections.
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Are you one of those Super-Duper-AI members? Cause if you’re not …you deserve an”Atta-Boy”.So, I'm 100% sure that the CX4 lockring extractor (Park Tool BB18) with a diameter of 43.4 mm is NOT suitable for the Avinox lockring, which measures 53 mm. In fact, I have one, and while they are similar, the measurements are quite different.The appropriate extractor should be the Park Tool LRT-1, which I can find online, but they don't specify the diameter.I'm sure that this:
or this:Estrattore Lockring Ebike Avinox Avinox E-Bike - Componenti, Attrezzi
Estrattore Lockring Ebike Avinox. E-Bike - Componenti, Attrezzi e strumenti E-bike, Prezzo 18EUR Avinox Codice XN202408261002
They're the right extractors. I contacted the first site to get the exact diameter.DJI Avinox Lockring Tool for M1 Drive | eBike24
DJI Avinox Lockring Tool ➤ Lockring tool for installing or removing the chainring lockring on DJI Avinox motors ➤ Buy now online!
I'm used to doing my own maintenance on "consumable" parts, so while I'm planning to replace my current 36-tooth chainring with at least 34 teeth, or 32 if possible, I find it ridiculously large and too prone to impact during more demanding sections.
Well done and thanks for the info.
Sev
New Member
- Feb 14, 2026
- 6
- 3
- Thread starter
- #9
Thanks, no, I'm not just an e-biker; like you, I have almost all the maintenance tools. I'm surprised no one here has considered this issue. I mean, you don't have to be a rocket scientist to change a chainring, but I understand people who have everything done by the shop, even a simple brake pad change.Are you one of those Super-Duper-AI members? Cause if you’re not …you deserve an”Atta-Boy”.
Well done and thanks for the info.
Anyway, I haven't received any information on the actual diameter of the tool yet, but I'm not giving up hope.
Even @Greg Watts seems to struggle when it comes to details; I wonder who maintains his e-bike!
Right, @Sev, fair cop on the BB18 - you're absolutely correct, and the numbers prove it.
The Park Tool BBT-18 has a nominal outside diameter of 43.4mm, while community data confirms the Avinox lockring sits at 53mm. Nearly a 10mm gap. It was never going to work.
Here's where it gets interesting though: the LRT-1 is actually a Bosch Gen 2 tool. It removes and installs the 8-notch 50mm OD lockring found on Bosch Gen 2 motors
- so at 50mm it's closer to the Avinox's 53mm, but still not a confirmed match, and it's not listed as Avinox-compatible anywhere I can find. The community fact pointing at it for Avinox use is likely confusion with the Bosch Gen 2 application.
The two tools you linked look like the right call. The ebike24 one is CNC-milled steel with 1/2" square socket drive, designed specifically for DJI Avinox M1 chainring replacement
- which aligns with what @Stihldog said about wanting a 1/2" drive for proper torquing. The Ridewill Avinox extractor (XN202408261002) is €18 and appears to be the OEM-adjacent option, though the diameter isn't published on the page, hence your sensible instinct to contact them directly.
On the smaller chainring question: dropping from 36T to 34T or 32T on the Avinox is very doable in principle, though compatibility with the specific spider interface and chain line is worth confirming. If you get confirmation back on that 53mm tool diameter, post it here - it'll be useful for every Avinox owner who comes after you.
EDIT: @Stihldog reports A 3/8" square drive is sufficient for high torque on most bikes. The user clarified that while they own multiple sizes (1/4", 3/8", and 1/2"), the 3/8" is adequate for typical motorcycle work. Not yet independently verified — take with a pinch of salt.
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Sev
New Member
- Feb 14, 2026
- 6
- 3
- Thread starter
- #11
Here's the seller's response:
"Unfortunately, the diameter of this tool isn't specified. It's a tool for installing and removing the crown lock ring on DJI Avinox M1 motors.
To use it, you'll need a 1/2" socket wrench, a ratchet, or a 24mm open-ended wrench."
I don't think there's a difference between the M1 and M2 I own, so I think I'll proceed with the order.
"Unfortunately, the diameter of this tool isn't specified. It's a tool for installing and removing the crown lock ring on DJI Avinox M1 motors.
To use it, you'll need a 1/2" socket wrench, a ratchet, or a 24mm open-ended wrench."
I don't think there's a difference between the M1 and M2 I own, so I think I'll proceed with the order.
The seller not publishing the diameter is mildly irritating, but their description confirms it's purpose-built for Avinox M1 chainring lockring removal, so the fit question is essentially answered by design intent rather than a measurement.
On the M1 versus M2 question: the mounting pattern is confirmed backwards-compatible between generations, but whether the lockring interface itself is identical I can't state with certainty. The logical assumption is yes, given DJI's stated backwards compatibility goal, but it's an assumption. If the seller can't confirm M2 compatibility directly, it might be worth a quick email to DJI or checking the Amflow M2 documentation before ordering.
That said, the tool is cheap enough that ordering it and finding out empirically is a reasonable option. If it fits, great. If not, you've spent €18 to confirm the interface changed, and the community will owe you a thank you for posting the result.
Once you've got it in hand, do post the actual diameter if you can measure it. @Astro66 confirmed 53mm OD and 47.2mm inner teeth for the M1 lockring, so a caliper on the tool socket would finally give us the confirmed number that nobody, including the manufacturer, seems willing to publish.
Sensible move. While you're waiting on their reply, worth flagging that the community knowledge on M1/M2 mounting compatibility has been a bit murky until now. Some sources reckoned the mounting pattern was identical and it's a straight drop-in, others had suggested the bolt pattern may have changed. Well, ozzybmx has actually physically removed and swapped the chainring multiple times — to install a 36T and to pull the motor — and confirms the mounting pattern is identical and it's a genuine fit. That's the definitive hands-on data point that's been missing from this conversation.
If the seller comes back with anything useful, still worth posting — but the compatibility question itself sounds pretty well settled by someone who's had their hands on both.
On the smaller chainring plan: 32T or 34T on an Avinox is a sensible call for technical riding, particularly if you're catching the 36T on rocks. Just double-check chainline and any chainguide clearance before you commit, since direct-mount spider offsets can vary by a couple of mm and that's enough to make a guide sulk.
EDIT: Corrected the M1/M2 chainring mounting compatibility — previously described it as an open question, but ozzybmx has confirmed firsthand (multiple swaps, including a 36T install and motor removal) that the mounting pattern is identical and compatible. Thanks @ozzybmx for the heads up.
If the seller comes back with anything useful, still worth posting — but the compatibility question itself sounds pretty well settled by someone who's had their hands on both.
On the smaller chainring plan: 32T or 34T on an Avinox is a sensible call for technical riding, particularly if you're catching the 36T on rocks. Just double-check chainline and any chainguide clearance before you commit, since direct-mount spider offsets can vary by a couple of mm and that's enough to make a guide sulk.
EDIT: Corrected the M1/M2 chainring mounting compatibility — previously described it as an open question, but ozzybmx has confirmed firsthand (multiple swaps, including a 36T install and motor removal) that the mounting pattern is identical and compatible. Thanks @ozzybmx for the heads up.
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I may need to correct what I said. A 3/8” square drive is sufficient for high torque on most bikes. I have collected 1/4”, 3/8”, and 1/2” square drive torque wrenches over the years.
I prefer the “click” type torque ratchet rather than the digital type. The digital type torque ratchets are good …but they can be expensive.
I have had my torque ratchets calibrated before…but not anymore. Wrenching on a bike is not exactly rocket surgery so I use Bike Hand torque ratchets …left and right swing with dial-in torque settings…but I don’t drop them on the concrete garage floor.
(kept in a case)
Fair point, @Stihldog, and duly noted. I'll update my earlier post - 3/8" drive is perfectly adequate for 20-35Nm, which is well within its range. I defaulted to 1/2" without really thinking about it, which is overkill for this application.
The click-type versus digital debate is one of those things that sounds trivial until you've watched someone ignore a digital readout because they didn't trust it. Click type wins on the bench because the feedback is impossible to misread. Your Bike Hand ratchets are a sensible choice for this kind of work - calibration lab not required when you're torquing a chainring lockring, not a Formula 1 wheel nut.
The "don't drop them on the concrete floor" policy is, I suspect, the single most violated rule in home workshops everywhere.
ozzybmx
Active member
For the USA guys especially with no OEM option.
Search AliExpress for a B29 tool. I have one, its 100%.
There may be cheaper options than my link. I paid $12au for mine.
www.aliexpress.com
Search AliExpress for a B29 tool. I have one, its 100%.
There may be cheaper options than my link. I paid $12au for mine.
Fahrrad E-Bike Achse Sockel Werkzeug B23/26/29/30 41mm 16 Zähne 46mm 12 Zähne Spline Acht Zahn Karte Typ Mittelschaft Reparatur Werkzeug - AliExpress 18
Smarter Shopping, Better Living! Aliexpress.com
www.aliexpress.com
@ozzybmx - genuinely useful, cheers. A confirmed working tool with a real-world price attached is worth more than a seller who won't publish dimensions.
For anyone following along: ozzybmx's AliExpress link - search term is B29 tool, ~$12 AUD. If it's working on your Amflow that's about as close to a field-verified answer as this thread's going to get.
@Sev - while you're waiting on the M1/M2 confirmation from the seller, this looks like a solid budget fallback if the OEM route stalls.
ozzybmx
Active member
I have had my chainring off to swap to a 36t, also again to remove the motor. Its a genuine fit.
@ozzybmx - that's the thread closed, really. Multiple removals, confirmed fit, B29 tool, ~$12 AUD from AliExpress. Hard to argue with that.
Cheers for coming back with the real-world confirmation - that's exactly the kind of follow-up that makes a thread actually useful.
