Is the Shimano EP8 a bad motor?

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We see some comments about how bad the Shimano EP8 motor is. Some claim it’s a dangerous motor that suffers spindle failures. Some say it’s unreliable with a high risk of getting bricked. Others will tell us the EP8 is a weaker motor.

We haven’t really got an opinion about durability. We test a lot of different motors but never ride the same motor for several hundred kilometres. So we asked 4 local shops, or should I say 3!? All of them are big shops that service a lot of ebikes, mostly Bosch, Shimano and some Yamaha. This isn’t a proof of anything, just the opinion of the guys we happened to talk to. None of the shops had any data of motor systems sold versus motors returning with a failure.

Power?

How about motor power? We did a comparison of the Bosch Performance CX 85 Nm against the Shimano EP8 85 Nm a while ago.

  1. Before buying an Ebike 3 years ago i started reading a lot and i still read about Ebikes.
    None of the Shimano atracted me, they are not reliable.
    The 7,000, the 8,000 and the new one.
    Motor or battery etc… way too much problemsssss.
    Without a car i ride Ebikes 350 days each year.
    A bike in the shop means i have PROBLEMS.
    My Ebikes are problem free.
    The Shimano have not been reliable in the last 4 years.
    If you like reliable read, ask, find a good or great Ebike.
  2. I’m not convinced the E8000 is any more unreliable than the Bosch. D From what I’ve seen in my own group of friends, the difference is that Bosch support their motor unconditionally, whereas in the UK Shimano/Madison appear to want to wash their hands of it whenever possible.

    I’m going to sell my Merida as soon as I can lever a new motor out of Madison, and I’m replacing it with a Rail. An expensive mistake to have made.

  3. I put my bike (Commencal SX with the E13 cranks) into my local bike shop mid January for a yearly service, he calls to tell me the spindle is cracked, organises the warranty claim for me, sent the motor to Shimano, the motor gets sent back with the warranty denied, so I contact Commencal, they organise the warranty claim again and I believe (hope) it is being fixed now. Can’t say that I am happy about the bullshit runaround regardless of where the fault lies between cranks or motor. So far 2½ months and no bike yet.
    I love Shimano brakes and shifting but I don’t think I will go to another bike with a Shimano motor again due to how they handle their claims, at least in Australia anyway. Worth noting that Commencal are going to replace the cranks with Shimano cranks as well when they get stock.
  4. The complete lack of repairability, plus a battery that has lost a significant amount of capacity in less than 8 months, means I won’t get another Shimano ebike.

    I wish reviews would focus on this sort of thing rather than comparing how much torque they’ve got and how fast they are up climbs and so on.

    As a customer, we have pretty much zero ability to communicate with Shimano, it all goes through shops, so perhaps if reviews highlighted this they might take some notice.

  5. Ease of service might be different in different parts of the world. Around here, Shimano has been fairly easy to deal with. I’ve had issues with Bosch, Yamaha and Shimano on my own bikes. But it’s been a while ago, back before I did many reviews.

    Bosch was dificult, they wanted to inspect the unit in Germany before making a decision, so any warranty claim would take weeks. Shimano was easier, a Shimano cerified service center could do the job. For Yamaha, I went to the distributor of the bike I bought, Haibike in my case. That worked well too, but it can depend on the company that handles the import and distribution in your country.

    With Bosch, a bike shop can stock parts/motors, and they can decide if the issue is warranty and swap the part them selves. In that case any warranty repairs can be very smooth. It can be worth having a good LBS that has the resorces to take care of me. There is a real risk of failure with any brands. Especially regarding Shimano vs Ethirteen cranks. In my experience, Shimano seem to stand behind their products as long as the bikes are built with approved parts. In this particular case, it seems the bike manufacturer is taking the responsibility.

  6. What about “ease of service” after the warranty expires ?

    In your part of the world are there third party e motor repair shops starting up and if so do they repair out of warranty e8000 and ep8 motors ?

    I‘m in the UK, there are third party repairers starting up but to my knowledge there aren’t any 3 party repair shops who are prepared to work on the e8000/ep8 motors(Bose, Bosch, Yamaha are covered). This, in conjunction with my experience of the e8000 (1st motor, failed at 2000 miles, 2nd motor, starting same type of fail at 1000 miles) and nobody was prepared/available to rebuild iI means that I just decided not to buy an orbea rise m-ltd (*it was even in about a 15% off sale) most irritatingly it was exactly what I want, a lighter, full fat ebike with an add on battery extender but in my experience it would likely prove very costly out of warranty.

    In my opinion its a bad motor, because of its lack of built in rebuildability, I liked the performance/behaviour/controls of my e8000 and I’ve deliberately bought shimano bike running gear since about 1990 as it works really well but until they produce a motor that can be rebuilt I’ll be avoiding them as a motor supplier.

  7. It would be valuable to know the mode of failure before passing judgement. If the E13 crankset causes an issue, can’t blame Shimano for that!
  8. Todos los motores que tienen componentes electrónicos y engranajes juntos no duran mucho.
    Mi Canyon Neuron ON con 26 meses y 13,100 km de senderos y pistas en su haber todavía funciona bien, pero tengo que encontrar otro E8000 para reemplazarlo, como hago con el Cassette, la Cadena, las Ruedas dentadas, etc. Creo que deberían venderse en tiendas de bicicletas que venden ebikes con motor Shimano y por no más de 850 euros. No entiendo la cantidad de gente que se gasta más de 150 euros en rodamientos, grasa, sellador de juntas y se arriesga a desmontar un motor y la mayoría de las veces va cargado o le dura 1500 km más. No te gastas 1.000 euros en una horquilla nueva, porque la mejor inversión es un motor nuevo, sobre todo si se han pasado los dos años de garantía. Para mí, los mejores motores son Yamaha y Shimano. Creo que Yamaha es más confiable (comencé en 1955 con la bicicleta YA-1, yo tenía una Yamaha-TY-80), pero Shimano Steps brinda una mejor imitación muscular,
    Mira este video es muy interesante.

  9. What about “ease of service” after the warranty expires ?

    Yeah, you’re right! I’ve got no experience with that, only how warranty requests/repairs are handled. We are so fortunate to have 5 yrs of warranty here. So it’s mostly just a few Yamaha PW and Bosch Performance (not CX) emtb motors that are out of warranty so far. I ask Shimano about repairability every chance I get, and I will keep doing it. As I say in the video; yay right to repair!

  10. When I was researching what bike to buy last year many of the bikes I was interested in had the EP8 motor in, after reading about the issues with reliability and dealing with warranty claims they were all crossed off my list.
    If things improve then maybe I’ll reconsider in a couple of years when I might want to replace my bike.
  11. Over on the USA MTBR mountain bike (ebike forums) forums, there are a very large number of posts about people left hung to dry with the Shimano motors. What is interesting to me is how many e-mtb manufacturers have gone all-in with the Shimano ebike drive system. Makes me wonder if Shimano has done some undercutting as the lowest bidder in order to become the exclusive ebike drive manufacturer of that particular bike brand.

    Just a couple of observations"

    1. Regards to the first video, it’s not reasonable to expect any bike shop owner who deals with Shimano to outright bash the product "on camera". No, the only place our two youtube v-loggers are going to find their questions about Shimano reliability answered are in forums like this one and over on the USA MTBR ebike forum. The answer lies with the bike owner; not some shop owner who depends upon Shimano to make a living.

    2. Regards to spindle cracking; looking at how lightly built that spindle appears to be, it behooves every Shimano rider to avoid pedal strikes at all costs.

    Good points!
    This thread is really dissapointing to read. I have a Yeti E160 on order. Its just astonishing to me that Yeti would put that motor into a $13k bike with all the research and design work that went into that bike.

  12. wow, 5yr warranty – that would be fantastic, in the Uk it’s normally 2 years on the motor. If we got a 5 year warranty I’d still say I would be disappointed in the non repairability aspect but I reckon I could accept a max cost of £200 per year on the motor (*call a motor £1000 in the UK, so spread over 5 years minimum as opposed to 2).

    As an alternative maybe shimano should start selling reconditioned engines, with a 2 year warranty, (*surely they must be able to rebuild them and deal with the software) that would both prevent waste and provide a cheaper way to keep customers happy once out of warranty. (? does anybody know what happens to all the warranty return motors).

  13. At the price paid for a Shimano Ebike i cannot afford 2 so even if they replace or repair free it is not attracting.
    I want to pedal, recharge, repeat.
    WAKE UP shimano.
  14. Good points!
    This thread is really dissapointing to read. I have a Yeti E160 on order. Its just astonishing to me that Yeti would put that motor into a $13k bike with all the research and design work that went into that bike.

    As a followup…Yeti gives a lifetime warranty on the frame. The motor and battery are integral to the frame. There is no mention of the motor warranty separate from the lifetime warranty. Hmmm.

  15. As a followup…Yeti gives a lifetime warranty on the frame. The motor and battery are integral to the frame. There is no mention of the motor warranty separate from the lifetime warranty. Hmmm.

    Yeti treat the motor as a separate component from the frame, so you’re stuck with whatever the Shimano warranty is in the country of purchase unfortunately 🙁

  16. Yeti treat the motor as a separate component from the frame, so you’re stuck with whatever the Shimano warranty is in the country of purchase unfortunately 🙁

    Yeah I’m sure it falls under the 2 year Shimano warranty, but if a layman just reads the literature they could be mislead.

  17. No idea what you are all worried about, just get a Bosch. Worry free miles.

    I just have @TheBikePilot follow me on every ride.

    He carries a couple of basic spares on his bike so in the event of motor failure I can make a trail side repair:

    View attachment 85324

  18. I have done 3400Ks on a Merida E160 10K. Has the ep8. Been 100 percent reliable. I have had two Shimano relate problems that were either operator error–broken battery release, or 2 a broken control cable due to factory assembly of the internal routing of cable through the stem.
    The biggest EP8 issue is the range/power. No matter what I do, there is no way to match Bosche and Brose on this bike. Much is dad about the EP8 being a natural feeling motor, and thats true. But what is also true, is that this is a deflection from the fundamentals. Basically in my exhaustive tests the Bosche gives 25-30 percent more range for similar power – tested on timed runs on a control climb with same heart rate.
  19. Basically SHITMANO is a scheme.
    It has been for 4 years.
    Stop buying shit.
    Manufacturers and retailers will make better offers.
    I will not pay money for a lighter motor
    I will not pay for a smoother motor
    I want somethings that works in real life not just on paper.
    Vote with your money, boycot the SHIT . . . .
  20. I have done 3400Ks on a Merida E160 10K. Has the ep8. Been 100 percent reliable. I have had two Shimano relate problems that were either operator error–broken battery release, or 2 a broken control cable due to factory assembly of the internal routing of cable through the stem.
    The biggest EP8 issue is the range/power. No matter what I do, there is no way to match Bosche and Brose on this bike. Much is dad about the EP8 being a natural feeling motor, and thats true. But what is also true, is that this is a deflection from the fundamentals. Basically in my exhaustive tests the Bosche gives 25-30 percent more range for similar power – tested on timed runs on a control climb with same heart rate.

    Exactly my experience with E8000 too.

  21. No idea what you are all worried about, just get a Bosch. Worry free miles.

    ha, good one – I’m on bosch motor number 2, and kiox display number 2.

    I think the reality is that currently all motors have issues , there is no one motor that is perfect, but it seems the bosch is the best of a bad bunch to me.

    I’ve got 3 mates with the shimano ep8 – one of them is on his 3rd motor in about 400 miles, the other two have been fine – but they dont ride very often

  22. I think the reality is that currently all motors have issues , there is no one motor that is perfect, but it seems the bosch is the best of a bad bunch to me.

    The big difference in the UK is that Bosch appear to sort the problems quickly and with no argument. That’s worth a lot.

  23. The big difference in the UK is that Bosch appear to sort the problems quickly and with no argument. That’s worth a lot.

    I was chatting to the owner of my LBS last week when I went in to collect my mates EP8 motor’d bike after having a new motor (the 3rd motor) fitted. This LBS is a bosch , shimano and specialized dealer, he was saying that all of them are easy to deal with in terms of motor warranty repairs/replacements, which clearly doesnt tally with some shimano owners on here experiences.

  24. I don’t understand the comments about reliability for Shimano motors compared to other brands

    Nobody is complaining about reliability. Well, I guess that’s not entirely true, but the point is, many of us are finding that Shimano are reluctant to help when there is a problem. Every ebike I ride with has needed a new motor. All four Bosch bikes have had the motor replaced no questions asked. I’m still arguing about mine (E8000). That, coupled with the E8035 battery which is absolutely garbage, is why I don’t like Shimano.

  25. Can’t comment on Bosch motors but had a 1st Gen Heckler with the E8000, and motor was way too abrupt with power, which made techy uphills really frustrating. The thing went through a battery very quickly on long climbs. I had a Bullit on order but cancelled after reading about battery life. Instead went for a Gen3 Turbo Levo and have been super happy with the Brose motor and battery life. Unless the successor to the EP8 is a huge improvement I will not buy a bike with a Shimano motor. Right now for me it’s either Brose or probably Bosch.
  26. Los ingenieros diseñan motores más compactos, ligeros y potentes.
    Eso es lo que hacen.
    Pero hay dos limitaciones en estos motores; Bosch, Shimano, Brose y Yamaha que son las mejores que probé:
    1) La unión de electrónica y mecánica aguanta mal el paso del tiempo y el kilometraje.
    2) Cojinetes con vida limitada ya que la lubricación no es constante.
    Si solucionan esto los motores podrían durar 100.000 km, pero pesarían más y durarían mucho más.
    Ni los fabricantes de motores ni de bicicletas están interesados.
    Si consideras el motor como una pieza más de desgaste, como el cassette, plato, cadena, discos, pastillas, etc.
    y no lo lavas mucho, con suerte te puede durar entre 10.000 y 15.000 km.
    Buena suerte.
  27. Los ingenieros diseñan motores más compactos, ligeros y potentes.
    Eso es lo que hacen.
    Pero hay dos limitaciones en estos motores; Bosch, Shimano, Brose y Yamaha que son las mejores que probé:
    1) La unión de electrónica y mecánica aguanta mal el paso del tiempo y el kilometraje.
    2) Cojinetes con vida limitada ya que la lubricación no es constante.
    Si solucionan esto los motores podrían durar 100.000 km, pero pesarían más y durarían mucho más.
    Ni los fabricantes de motores ni de bicicletas están interesados.
    Si consideras el motor como una pieza más de desgaste, como el cassette, plato, cadena, discos, pastillas, etc.
    y no lo lavas mucho, con suerte te puede durar entre 10.000 y 15.000 km.
    Buena suerte.

    Engineers design more compact, lighter and more powerful engines.
    That’s what they do.
    But there are two limitations on these engines; Bosch, Shimano, Brose and Yamaha which are the best I tried:
    1) The union of electronics and mechanics does not hold up well over time and mileage.
    2) Bearings with limited life since lubrication is not constant.
    If they solve this the motors could last 100,000 km, but they would weigh more and last much longer.
    Neither engine nor bicycle manufacturers are interested. If you consider the engine as one more wear part, such as the cassette, chainring, chain, discs, pads, etc. and you don’t wash it much, hopefully it can last between 10,000 and 15,000 km.
    Good luck.

  28. Good points!
    This thread is really dissapointing to read. I have a Yeti E160 on order. Its just astonishing to me that Yeti would put that motor into a $13k bike with all the research and design work that went into that bike.

    To be fair I would cancel the order !!!

    I have a 8.5k orbea rise and if I knew what I knew now I wouldn’t buy sadly

  29. To be fair I would cancel the order !!!

    I have a 8.5k orbea rise and if I knew what I knew now I wouldn’t buy sadly

    What would you get instead?

    Not had en Ebike for a few years so it’s disappointing to hear that motor reliability has not improved. The Rise was top of my list.

  30. All motors can have faults, but with Shimano it is not repairable outside warranty (other than doing bearing changes).
    Options are:
    – nearly 1000 pounds from a Shimano dealer for new motor
    – an ebay motor with no warranty
    – get a new bike / frame.

    Other manufacturers motors are to some degree repairable.

  31. You all are making me wonder how many miles I’ll get out of the Bafang m620!

    Availability of experienced local service, & parts, was part of what made me OK with buying a Bafang drive. (That, & a lot of research to determine that I could do better than the commonly applied configs!)

    The shops around here *know* Bafang motors: Even the mid-drive Ultra, can be found all over the place. My *hope* was that the model would proliferate, leading to a long maintainability lifespan.

    (With Bafang now joining in the proprietary anti-repair vendor lock-in crap, on their newer controllers, I worry their ubiquity may plummet precipitously & doom these new m620 motors to a foreshortened lifespan.)

    Coming up on 200 miles & it’s been great so far (once the torque sensing was calibrated, anyway!)… 🛣🏞💪

    It’s a powerful motor. (I often run at a max of 7% power.) Took some doing, to get the pedal torque response, dialed in so it’s proportional, instead of feeling like it’s all-or-nothing.

    I keep finding myself trying things I normally wouldn’t…

    Hopefully it continues to perform many more hill climbs as well as it does now!?

  32. I was recently in the market for a new ebike and discounted anything Shimano. Noisy and not great support, shame as I fancied a heckler
  33. Ford, Chevrolet, Dodge, It’s the same here in North America with our trucks.

    What are the percentages of Shimano motors in bikes?

    Over here there are more Ford trucks sold every year by a large margin. More bad publicity with reliability issues, but Ford trucks are more common.
    Is this the case with Shimano motors?

    I’m on my second Ford F-150. In over 10 years they have never left me stranded, nor had any major issues.

    I’m on my first EP8 that’s in my new 22 Heckler. Absolutely in love with this machine! We shall see about the motor. Had I read the bad publicity with the Shimano motors before buying, I still would have. And I’m so glad I did!!

  34. 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.
  35. Ive had both of my Shimano batteries die while there was nothing obviously wrong with it. They just bricked themselves. Ive got them somewhat working again by bypassing the battery BMS, but its far from perfect. My Shimano E8000 has had its bearings replaced and now needs a new clutch mechanism. Obviously shimano doesnt provide these parts so im stuck with finding a donor motor and use those parts.

    I will not be buying shimano for my next emtb.
    Its not even that the motors are designed poorly (most of it is pretty ok), its just the way they handle errors, faults, spare parts and returns.

  36. What would you get instead?

    Not had en Ebike for a few years so it’s disappointing to hear that motor reliability has not improved. The Rise was top of my list.

    You could research the rise here – there is a fair bit written about people’s experience with it.

  37. I can’t comment on the other manufacturers as I haven’t owned them, and a lot of the discussions about reliability between brands is anecdotal.

    I’m personally not happy with the shimano system I’ve got. The battery is degrading fast and shimano don’t want to know. My first bike (which I’ve given to my dad) has a bearing failure and my current bike had an electrical issue. Both under 2000miles, which I think is poor.

    I do wonder how much of the problem with the service is the bike shops though? Mine said they expected a replacement motor in 48hrs and they have never had an issue. It was delayed in the end, but only because they had no motors in the UK.

    My dad is having o end of trouble on the other hand. But it sounds like they have never replaced a shimano motor and so don’t know the procedure.

    FWIW, my LBS said shimano and Bosch are similar with warranty replacement, and both have been fine in their experience. They’ve also replaced a similar number of each.

  38. After 9 months of intermittent arguing, I’ve finally got a new E8000 motor for my Merida. The actual replacement only took about seven days from the LBS sending the old motor to Madison to the new one being back and fitted, so no complaints there. Shame it was such a slog to get it sorted though.

    Now to force the issue of the dodgy batteries. I’m hoping to get at least the original, knackered battery changed, but then the bike is going. I don’t want to own a bike with such a low level of manufacturer support.

  39. l’ve got a Kona with the Shimano E8000.

    After over 3,000 miles (around 5,000km) of thrashing in all weathers here in the U.K., the motor is still perfect.

    My friend has a Cube with the Bosch Gen 4 motor. He’s on half the mileage l have done, His motor failed twice when out on rides with various error codes and we’ve managed to get it going again. The third time it failed it had to go back to the shop and they had it over three months before it was repaired.