Article Is the Shimano EP8 a bad motor?

[Bontee]

Update to earlier post on this thread,now hit 2500 miles on my ep8 ,still running perfectly (yes I know that isn’t a huge mileage) on the original chain and cassette,just switched the chainring for a burgtec.I haven’t touched the app since I set it up the bike which has been through 2 winters ,deep water ,and been drenched frequently,no issues.I would say again,there are dozens of ep8’s out there doing just fine for every one that is complained about on forums like this (and rightly so if they are duff motors) but I personally know 2 guys who have had bosch failures and non so far with ep8 failures .I have no brand loyalty here,the bike I wanted came with an ep8,I would have bought it whatever motor was fitted.It just happens that my ep8 has (so far ) been faultless.That might change.

 

[Bontee]

This is great, you are lucky you do not read. You probably ignore Shitmano batteries die young.
I love the excuse lots of complaints because we sell lots.
That is a ton of BS.
In the last 4 years i read many reports with lots of kms trouble free on Yamaha.
Why did i not read tons from Shitmano if they sell soooo many more?? ???? ??????
Please let us know how your motor and battery are doing in 3 years.

Can’t tell you how it’ll be doing in 3 years but I can tell you that 2700 miles ( 200 in the last month) 2 and a half years with my ep8 and 630 battery and after setting up the app on day one haven’t touched it since.The bike has been dragged through it’s 3rd winter,mud,torrential rain ,river crossings and hasn’t missed a beat and the battery is still as good as the day I bought it.
Go figure !

 

[mustclime]

Hose = e motor death. Dry wash FTW

 

[Jil]

I don't know about the EP8, but my EP801 is the best motor I've ever tried.

 

[Jil]

The EP801 also has a magnesium-aluminium frame (that’s the main difference compared to the EP6). The DJI is one of the few motors I haven’t tried, but I’m not looking for the most powerful motor here, nor for a system designed exclusively for internal batteries.

 

[steve_sordy]

I sold my first emtb with a Shimano e8000 motor on it. 3600 miles, three British winters, flawless.

But because of their policy of not designing for repair and their lack of co-operation with companies that do repairs, I decided that I was not going to get another bike with a Shimano motor. I would vote with my money!

Well, that resolve didn't last long! I fell in love with my next bike and it had an EP8 motor.
That has now done over 3600 miles and it too has been flawless. It has been through four winters and it is as silent now as it was 3 months after I bought it. (It was noisier at first). I have rocked the crank in all directions and there is no movement that I can detect. I asked my LBS about sending it for a service and they checked it over and said "there is nothing wrong with it, let sleeping dogs lie!"

What I like about the Shimano motors is the way they deliver power. They always make me feel like I'm having a really good day and not just sat astride a MOTOR. I have tried other manufacturer's motors and they always feel to me like I am definitely astride a MOTOR. The last different motor I tested was a Panasonic onboard a Kelly's hire bike. The motor had more torque than the EP8 but the power delivery was all over the place. It wasn't until I put into AUTO that the bike settled down.

I have now done 7 winters and over 7200 miles on two different Shimano motors and I have been delighted by my experience. I have never used a jetwash, not even a hosepipe. I use a watering can and the cheapest car shampoo that I can find. Whilst I always keep the stanchions and the chain clean, I only wash the bike when its mucky. I often just brush off dry muck instead of washing it again.

But would I buy a third bike with a Shimano motor? If the bike I wanted had a Shimano motor, it wouldn't put me off, but the two bikes I have my eye on* are each supplied with a Bosch motor. Hmmm.

Note* Whyte Kado, Santa Cruz Vala.
Later Edit: I have gone off the Kado for the simple reason is that it looks like a tank. It does not have the "Look Back Factor" that is an essential for me.

 

[Bontee]

The EP801 is the second-best Shimano Stepper motor, after the DUE8000. But they're obsolete. The DJI Avinox motor truly seems to set a revolutionary standard in the e-bike world. Its compact design, advanced materials like magnesium/aluminum, and innovative features like the double-reduction planetary gear system and noise-reducing fiber pinions position it as a far superior competitor to traditional options from Bosch and Shimano. It's frustrating that, after more than a decade, established brands haven't prioritized durability and resistance to adverse conditions like water ingress or bearing and gear wear. Consumers deserve systems that not only perform well in ideal climates but also withstand intensive use in all types of environments. Avinox seems to have listened to these needs, offering advanced engineering with durability expectations exceeding 15,000 km without preventive maintenance and an internal design that reflects quality and foresight.

The Avinox does look promising,please correct me if I’m wrong but it is a very new motor and notwithstanding the apparent upgrades to reliability ,it does not have a proven track record to speak of …yet.
I really hope it proves to be a game changer,But like everything else it needs time in the field to expose any defects.
I am really not hating on anything regarding the Avinox (or any other motor come to that) I just feel it needs time to prove itself,how many times have we been made promises that fall flat.

 

[DylanJM]

The Avinox does look promising,please correct me if I’m wrong but it is a very new motor and notwithstanding the apparent upgrades to reliability ,it does not have a proven track record to speak of …yet.
I really hope it proves to be a game changer,But like everything else it needs time in the field to expose any defects.
I am really not hating on anything regarding the Avinox (or any other motor come to that) I just feel it needs time to prove itself,how many times have we been made promises that fall flat.

How long does it need? It's been out for almost a year at this point. Don't think I've seen any more complaints on here or other places than I have for any other major motor brand so I would say it's safe enough to say it's has at least matched the current standard mark for motor reliability.

 

[Bontee]

How long does it need? It's been out for almost a year at this point. Don't think I've seen any more complaints on here or other places than I have for any other major motor brand so I would say it's safe enough to say it's has at least matched the current standard mark for motor reliability.

That’s a good question Dylan,I agree that it appears to be no better and no worse than any other motors at the one year point.I was simply addressing the comments made regarding the claimed improvements in durability compared to the rest.
When any new motor comes out be it Shimano ,Bosch or any other there tends to be a honymoon period where everything is great ,then things show up,often outside warranty.
Like I said I’m not hating on any motor,I have no axe to grind here and to date my 4 year old shimano EP8 is still going strong and the battery is perfectly fine.
You just asked How long does it need,my answer would be this,
It would need to prove it can run trouble free for the warranty period ( I don’t know how long Avinox warranty their motors for) and then at least a couple of years after that.
Even then it would only be as good as my EP8 ,so 4 years minimum.
12 months is nothing
All the best

 

[Jil]

You're right. We'll have to do a few thousand miles to find out.

Are these your e-bikes? 40,000 and 98,000 km with Shimano and Bosch motors,; that’s quite an experience! What are your main takeaways?

 

[Jil]

Interesting ! Do you know if the EP6/EP801 are serviceable like the E8000 ? I mean, are there repairs kits available from third parties ?
Haven't you done any other maintenance than replacing gears and bearings ? No need to grease gears between 2 replacements ?
You mention 3 E8000, are the first 2 (including the one at 40.000km) still working ?

 

[Ndanger]

You're right. We'll have to do a few thousand miles to find out.

If my math is correct and the odometer shows 98,000 km, since the motor is less than a year old then we are looking at roughly 9000 km a month or 300 per day 7 days a week. Impressive. Converted to miles (180) per day and at 18 mph , 10 hours of riding each day of the week for a year. Impressive.

ps I am running the numbers without a calculator and early in the morning so not sure if I got it right.

 

[Jil]

If my math is correct and the odometer shows 98,000 km, since the motor is less than a year old then we are looking at roughly 9000 km a month or 300 per day 7 days a week. Impressive. Converted to miles (180) per day and at 18 mph , 10 hours of riding each day of the week for a year. Impressive.

ps I am running the numbers without a calculator and early in the morning so not sure if I got it right.

The odometers are respectively Shimano and Bosch models, not DJI

 

[Winford]

Shimano Steps motors are repairable

yes and no. the eP801 has a hidden trick you have to do when splitting cases or it bricks the motor, there are only bearings you can get online, no gears are sold anywhere, and generally the gears fail first. I have heard of one place in the UK that makes their own gears, and ive heard but dont know about a place in the USA.

The Shimano authorized service shop here says t does not mater what motor it is due to the hills here, he see's about 3000 miles out of every Ebike motor.

In 12 months of riding im on my 3rd EP801, 3 Rosenberger cables, and second battery, in about 6000 ish miles. But that is aggressive riding and some 800,000+ feet climbed.

Got a buddy with his EP801 he will get triple the miles I do, he always rides in ECO.

 

[Winford]

I shipped

Lucky you man, I tried to send back a Schwalbe 2.3 rear tire last week to a scammer on Amazon selling 27.5 Shreddas, they had me return it to Slovenia and UPS wanted almost $400 to ship a tire. He said USPS was almost $200. Took the tire home and got on the phone with Amazon, they said keep the tire.

For us in the USA with an EP801 your best bet is buy one off ali express $580 range or even a cargo motor.

 

[Winford]

. The DJI Avinox motor truly seems to set a revolutionary standard in the e-bike world.

That is what I bought for my fast runs, i use the EP801 now on recovery days. Im 17 months into the 24 month warranty period on my EP801, so im probably not getting a 4rth motor before the warranty is over. So im limiting miles on the EP801 now. Hence adding the Amflow to the stable. Glad I did, amazing bike.


Side note, even Shimano doe snot split cases on these motors. With the terrible reliability they have had, Canyon dropped them, no one else wants the headache either. I will be surprised to see how they move on to their next series.

 

[Tony4wd]

My EP8 became noticeably noisier approaching 2000km so I opened it up (after watching a few videos) and after having previously opened a Bosch CX4.
There was no water ingress and almost no grease, especially on the plastic gear that runs against the armature shaft gear. There were green shavings from the gear mixed with grease adjacent to the gear.

I regreased the motor with Molykote EM-50L (don't know if that's the best grease to use) but so far so good.

Very minor design modifications would have allowed much easier disassembly and periodic maintenance (by owners or bike shops).

 

[Jil]

I’ve put 3,300 km on my EP801 (installed on a cargo bike), and it runs flawlessly. Of course, my usage is different from MTB riders who always run it in Boost mode, I mostly use the motor with low and smooth assist.
I’ve heard great feedback from professional couriers about the EP8’s reliability, even on cargo bikes, though in flat areas.
That said, the lack of maintainability in these motors is a concern. I’ve shared this feedback with Shimano, and I hope other professionals are doing the same. In my opinion, they have one of the best motors on the market, this is the only major downside.

 

[Scott_123]

Most so-called EMTB reviewers say if the bike you are looking at is equipped with a Shimano motor, best to steer clear and move on. Main issue is support and reliability. Most people are saying unless Shimano comes out with something new that is competitive in its class they likely will pull out of the motor wars completely. Shimano is very slow to market with new components and they have always been this way. In some ways this is good but in many ways it is bad. Given the pace of advancement in EMTB motors Shimano is not likely to stay competitive unless the entire culture of the company changes.

 

[Bontee]

My EP8 became noticeably noisier approaching 2000km so I opened it up (after watching a few videos) and after having previously opened a Bosch CX4.
There was no water ingress and almost no grease, especially on the plastic gear that runs against the armature shaft gear. There were green shavings from the gear mixed with grease adjacent to the gear.

I regreased the motor with Molykote EM-50L (don't know if that's the best grease to use) but so far so good.

Very minor design modifications would have allowed much easier disassembly and periodic maintenance (by owners or bike shops).
View attachment 169880

Tony,I also run an EP8,and it has been trouble free for 4 years,I have heard that dismantling the motor crashes the software and this is why they are considered non serviceable,You clearly have taken your Ep8 apart so how did you get round the software/crash issue please.
All the best

 

[Winford]

EP8

only ep801 plenty of videos showing the cases being split on an ep8

 

[Bontee]

only ep801 plenty of videos showing the cases being split on an ep8

Hi Winford,yes I know they can be split but I understood that they wont work when reassembled due to a “feature” which crashes the software.This was my question and I suspect the reason why they are considered non serviceable.
Am I correct ?

 

[Scott_123]

Where are you though? UK? Some other regions seem well served.

US
I may be wrong, mostly what I am saying is based off everything I’ve read from the so-called EMTB reviewers.

 

[steve_sordy]

Most so-called EMTB reviewers say if the bike you are looking at is equipped with a Shimano motor, best to steer clear and move on. Main issue is support and reliability. Most people are saying unless Shimano comes out with something new that is competitive in its class they likely will pull out of the motor wars completely. Shimano is very slow to market with new components and they have always been this way. In some ways this is good but in many ways it is bad. Given the pace of advancement in EMTB motors Shimano is not likely to stay competitive unless the entire culture of the company changes.

SRAM (for example) are the innovators, Shimano the copiers - but they do a good job, no issuing beta versions for their customers* to test for them. I very much doubt that Shimano are stupid, so they will be fully informed of their place in the market and with be fully aware of their customer* feedback. They have options depending upon their attitude to their emtb motor product.
Negative: They will plough on, continuing to pay down the existing capital investment, making minimal further investment, bleeding it dry, until the motor brand dies through lack of sales. But this will harm their brand name "Shimano". I doubt they will do that.
Neutral: They will continue to invest. Hopefully they will make their next motor (EP9?) fully serviceable. Let's face it there are many satisfied customers* for their EP8 range, so they would be silly to turn their back on that. But this is still only a holding strategy as all they are doing is slowing down their customer's* flight to the competition.
Positive: Along with a serviceable motor, will come drastically improved performance and improved consumer* experience, then they will stay in the fight.

If Shimano are serious, then why are they not fighting all the negative articles and comments in the media. Have you seen anything from Shimano proclaiming the benefits of their motors? If they just stay silent, the negative press will continue to build until "everyone" believes that they are 100% crap and to be avoided.

Note*: Customer or Consumer? They are not the same people. A Customer is the one that buys Shimano products and pays their invoices. For motors (and batteries), that will mostly be the bike makers and the service agents. Shimano can do deals with them on other Shimano products to build a bundle of components that is very affordable, even for small brands with their low production runs. Consumers are the ones that actually use the products and they have different needs. Most will never buy a motor by itself. But Consumers are the end users, the ones that decide whether to buy a bike with a Shimano motor, or not! They drive the process; they inject new money into the supply chain. What they believe to be true about Shimano motors (whether correct or not) will matter, deeply. Consumers are not to be ignored!

 

[Tony4wd]

Tony,I also run an EP8,and it has been trouble free for 4 years,I have heard that dismantling the motor crashes the software and this is why they are considered non serviceable,You clearly have taken your Ep8 apart so how did you get round the software/crash issue please.
All the best

I've spent a lot of time reading posts and looking at videos of EP8 disassembly and it seems that the 'traps' inside the motor are mostly rumor. As a novice mechanic I was prepared for the possibility of ruining the motor but by going slowly the risk is minimized. I'm always cautious of static electricity when I handle circuit boards or other electrical components.

If I lived in the UK or other countries which have repair shops I'd be tempted to let them handle the job. There's nobody repairing them in Australia and I can get a new motor for less than it would cost to ship abroad and repair. (got a spare ep8 sitting here from Aliexpress ).

 

[Tony4wd]

For us in the USA with an EP801 your best bet is buy one off ali express $580 range or even a cargo motor

There's a repair guy for Shimano motors in the USA now, Grant Gunderson from PNW Suspension Service. He's on Facebook too.

PNW Ski and Suspension Service PlusE-bike motor repair

Mountain Bike Suspension rebuilding services, E-bike motor repair and Ski repair, service and mounting in Bellingham, WA

pnwsuspensionservice.com

 

[Bontee]

I've spent a lot of time reading posts and looking at videos of EP8 disassembly and it seems that the 'traps' inside the motor are mostly rumor. As a novice mechanic I was prepared for the possibility of ruining the motor but by going slowly the risk is minimized. I'm always cautious of static electricity when I handle circuit boards or other electrical components.

If I lived in the UK or other countries which have repair shops I'd be tempted to let them handle the job. There's nobody repairing them in Australia and I can get a new motor for less than it would cost to ship abroad and repair. (got a spare ep8 sitting here from Aliexpress ).

That’s very interesting,thank you for taking the time to reply,I might see if I can get hold of a scrap one from one of a couple of friends who are dealers and have a play,
All the best

 

[Winford]

EP8 disassembly and it seems that the 'traps' inside the motor are mostly rumor. As a novice

You have not done all your homework then. The EP800 does not have what you are talking about, but the EP801 does in fact have this feature and it will brick the motor. There is a video from Spain I believe, and the guy goes through the differences between an EP800 and an EP801, where he discusses the feature that will brick your motor. Im an expert mechanic, and without replacement gears, I wont split my case, ill just buy a new motor.

Grant Gunderson

Right, but all he does is what I mentioned above. He will clean and replace bearings. He does not have gears or offer them.

And his website does not say he works on EP801s. His shop also says he is the only one in USA to work on Shimano motors. There is another, but he refused to look at my EP801 as well.

 

[mmcengineer]

The EP801 is the second-best Shimano Stepper motor, after the DUE8000. But they're obsolete. The DJI Avinox motor truly seems to set a revolutionary standard in the e-bike world. Its compact design, advanced materials like magnesium/aluminum, and innovative features like the double-reduction planetary gear system and noise-reducing fiber pinions position it as a far superior competitor to traditional options from Bosch and Shimano. It's frustrating that, after more than a decade, established brands haven't prioritized durability and resistance to adverse conditions like water ingress or bearing and gear wear. Consumers deserve systems that not only perform well in ideal climates but also withstand intensive use in all types of environments. Avinox seems to have listened to these needs, offering advanced engineering with durability expectations exceeding 15,000 km without preventive maintenance and an internal design that reflects quality and foresight.

maybe they know something you/I/we don't? , for example the cost of the actual motor is negligible in the grand scheme of things hence the cost of a full replacement rather than dicking about with making something survivable / un/obsolete in a few years makes more commercial sense (brand perception is a different value metric to companies)

I remember working for a well known car manufacturer where the gear selector mechanism in the centre console was prone to failure,(there were literally skips full of them that were just returned seperated and recycled , but no where near the quantity that were out there in service, the part that failed was a bearing in the magnesium housing , the magnesium housing was a high pressure die cast magnesium part that cost in the region of £1.40 in fact iirc the entire replacement unit was less than 75 quid , anyway the cost of replacing the tool to manufacture the casting ,requalifying all the methods of production, fixtures, manufacturing lines etc, suppliers, SKUs was way more than just keep replacing the units when they failed iirc they made 750k of these things a year across all variants. there be higher powers where profit makes more sense than brand reliability and the virtue of oh well they just give me a new one carries some weight for some people whilst it doesn't for others