Updating Locked Shimano EP8 Motor to US-Region / Speed De-Restriction using eMax Tuning...

speedub.nate

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Region
USA
City
Oakland
This post is an offshoot of another thread I began 3 months ago concerning a bike build and an E8000 to EP8 swap:


The tl;dr of that thread is I wanted to install Nexus / Alfine Di2 shifting on a bike with an DU-E8000 motor, which isn't compatible, so I swapped in a Taiwan-market DU-EP800 (EP8) motor I sourced from AliExpress. Shimano USA remoted in to my motor and was able to adjust my wheel size and get my pushbutton shifting working, but was unable to switch the motor to "US-Region" which would be necessary to lift the 16 MPH speed limit. Shimano said that Taiwan-market motors specifically are locked out from them being able to make that change.

I began looking into my options and came up with "if your motor firmware is 4.1.1 or greater, don't bother, you're locked out from making changes." I found a few threads here and on Reddit that seemed to confirm that. eMax-Tuning's documentation said, in effect, you may as well stop reading because this won't work (but email us). So I DID!

My understanding is the eMax is comprised of a group of Shimano sTeps enthusiasts who became fed up with a lack of company support, so have been figuring out how to hack their motors. I wasn't excited about having to pay good money to make a change, but I gathered that Shimano closed some of the "free" loopholes a couple of years ago to the point that even their own US technicians were being put on ice. (For what it's worth, about 5 years ago I did very similar swap with an E6000 motor, and Shimano USA was able to remote in and make all of the necessary changes.) The contact from eMax who responded to my emails is named Markus. He was very responsive, replied to my email on a Sunday morning, and by mid-day Monday I was able to get my motor problems squared away.

The documents on the eMax site are chock full of information and a little difficult to digest. Maybe overwhelming? However, they are thorough, but benefit from the reader possessing a certain threshold of familiarity to make sense of.

I thought it would be good to document my experience here in case anybody else needs a walk-through.

So here's the breakdown of what was involved specifically with the EP8:

1. Download eMax miniMax or MobileApp (Bluetooth) software to talk to your motor. Connect, and send a screenshot to eMax (Markus) to evaluate how to proceed.

Of note: TW region specifically is locked and causes trouble. Markus says motors from the other regions wouldn't require the extra steps I'm documenting in this post. Shimano USA has already been in here to modify my wheel circumference and to activate my "electronical switching." Note also this motor was artificially limited to 400 watts. This is the screenshot I sent to eMax before paying for a license.

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2. Get a Shimano PCE-02 cable. Often this isn't necessary and can be done over Bluetooth, but in my case it was necessary. Great, I already have the cable.

eMax has documentation what changes are possible depending on what version firmware the motor has installed, and what is Bluetooth accessible vs. requires PCE.

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3. Download E-Tube version 4 (old) software from the eMax site; install it

I assume the newer version of E-Tube perform cryptographic verification of firmware before allowing it to be installed, so this older version is used. eMax notes that I don't have to uninstall the current v5 E-Tubes software, and sure enough, it installed to its own V4 directory.

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4. Download a E-Tube V4 "companion file" from the eMax site and unpack it in the V4 directory

I moved this Zip file right into the E-Tube Project directory, right-clicked, and extracted it there (highlighted files). I don't know what this file does

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5. Download old 4.0.2 firmware for the EP8 motor from eMax and unpack it, rename it

For this one, it needs to be deposited into a hidden Firmware directory. To make hidden directories visible, from your Windows file folder, click View, then Show > then Hidden Items

Screenshot (58).png


Just like the step before, I dropped the Zipped files here and extracted them.

After extraction, the files are named "D.4.0.0" (or whatever), and need to be renamed to a higher version ex. "D.5.0.0" to spoof the E-Tubes software into thinking it's the latest and greatest. Just right-click and select "Rename" from the dropdown to do this.

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6. That's it! Open Version 4 of E-Tube and connect to the motor. eMax instructions suggest to connect directly to the motor, but I connected to a vacant port on my head unit and this all worked fine. E-Tube will instantly see that there is an update available (the 4.0.2 files that were renamed to 5.0.2) and after you select it, it will run the update in about one minute.

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7. My bike was unlocked! You'll then disconnect E-Tube, and reconnect the eMax miniMax app. You'll find that the region and wheel size are no longer greyed-out, meaning they're adjustable.

The 400W limit is still in effect. That will revert to 500W after you reconnect using the V5 (current version) of Shimano E-Tube, and update the motor back to the current software version (currently 4.2.0).

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8. Reconnect using the newest version of Shimano E-Tube. Upon re-entering E-Tube V5 I received an "unauthorized modification" notification. The system prompted me to revert back to the previous configuration. Refuse this request. Proceed forward and perform the firmware update. Updating the firmware will eliminate this message from appearing again.

You will see a Update Available just like in Step #6, but this time will be reinstalling the real current firmware (4.2.0 in my case).

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What will be persistent is a warning on the Maintenance tab. There's really no issue with this, although Markus told me they have something that can be done to eliminate it. I don't want to bother as it won't revert the motor back to the previous configuration, and Shimano is never going to have this motor for warranty work since it's a gray market purchase.

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My intent with this post is to step you through what I consider the more confusing tasks associated with this operation, mainly what to do with the various files.

I don't know if the EP8 (specifically the Taiwanese market version of the EP8) is the only one with these challenges, but eMax seems to have a solution for most, maybe all, of the Shimano motors. Definitely worth the 100 Euros I paid them because of the comprehensive instructions, email support, and the flawless execution (particularly their app). It took me a little while to understand this, a few emails to get things set up, and maybe 30 minutes downloading files and extracting them to the right directories. But when I walked into the garage with my laptop loaded, the actual update process took mere minutes, no error messages or restarts, it almost felt wrong that it went so easily.
 
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Worth noting that if you look at my wheel circumference, in the first eMax screenshot I had Shimano set it to 2192mm, which is my actual rollout.

However now that I've got access to this setting, I divided my actual rollout by 1.6 (the ratio of 1.6 kilometers to a mile) to get 1370 mm. I also set my speed to be displayed in km/h. This sets my maximum assist speed to 32 MPH, and means that when I'm pedaling along at 20 MPH, my display will read "20" (km/h, but who's looking!). Saves me from having to install a defeat device and get basically a Class III bike.
 
Fascinating.

TLDR:

You swapped out the EP8 with a Taiwan EP800 to enable Di2, which worked, but the speed was locked, the power was capped at 250w, and you could not change the region to the USA.
An older version of EP800 firmware allowed region change, but you had to use a PCE-02 diagnostic cable and fool E-Tube to make it believe that you are updating, not downgrading.
Once it was downgraded and the region was changed, you were able to upgrade to the original version of EP800 firmware, which allowed unlocking to 25km/h and 400w.
You then used the latest version of E-Tube to update to the latest USA version of the EP800 firmware, which allowed wheel manipulation and bumped the motor to 500w. This cost you $100 euros and a harmless warning on the E-Tube screen.

Nice work.
 
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