What would you say has proven to be the most reliable emtb motor?

[Dave_B]

There are various posts all over this forum relating to motor problems, wiring harness problems, susceptibility to water while washing etc.

what in your opinion has proven to be the most reliable / trouble free emtb?

 

[Mteam]

Its only my perception, but it feels like the bosch cx gen 4 system is the most reliable to me, which is why I went for a bosch gen 4 motor'd bike.

And having put my money where my mouth is , my kiox display failed after 350 miles, rendering the bike unusable (not mid ride thankfully). I suspect it got water in it - probably through the crappy USB port cover.

Its hard to be objective about it though, and in my case it was easy to fix - new kiox display required.

 

[JoeBlow]

I don't think there are many on this forum who have access to data to "prove" anything. The nearest I got to what might be called data was when I asked a significant number of Levo users about their experiences because I was considering buying one. The number of people who had returned their bikes for motor replacement astounded me enough to put me off buying one so anecdotally I would say Bosch. I also seem to see more Brose and Bosch motors on the trail than any other but again that does not prove anything but for me between the two I specifically went for Bosch. To be fair I didn't research other motors as the bikes I liked were either Brose or Bosch and Bosch won out based on my very unscientific research.

Al

 

[Dirtnvert]

Ive seen enough stats to side with the bosch gen4 cx. ATM thats the way im leaning.
Like ski touring bindings i like to give new products, and the associated hype, atleast a year to show any flaws. Maybe in a year the fixes on the brose solve all the issues on an otherwise good platform or shimanos new ep8 proves the antidote to the e8000's flaws. Id have no problems with either one if thats the case , i think.
Right now bosch has a lot going for it with the new upgrade(tourque and features), warrantee, duribility, dealer support, and rebuildable.
Like stated above, a buddy had his kiox display die. He got it replaced in a day and no problems since

 

[Stihldog]

I’m currently working on an algorithm and a mathematical formula that will definitively show which emtb motor is the most reliable. I’ll post it on this site when its done.
Until then I’m gonna have to rely on factors that may not always make sense.

My first emtb (Rail 9.7) was purchased in 2019. It has the Bosch Gen4 motor. Since that time i have loaded almost 4000km without a single glitch. (Very lucky). I’ve rode in the rain, mud, dust, snow, had multiple crashes, submerged in mud and water several times, and even added a Kiox. I’ve also added His/hers Powerfly 5’s to the herd.

The Bosch gen4 seems to be the most popular in my area but i have come across a few Brose motors. These motors have not faired so well. One guy had to replace his Brose motor 3 times within a year, however the warranty was quite good. I’m sure the bugs are being worked out.
This seems like the early stages of mid-motor development, and each manufacturer is producing as best a product as they possibly can, otherwise they will vanish.

I think what’s most important to me is the proximity to my LBS, which happens to be Trek. Ive developed a relationship with them and unfortunately most of the reps and mechanics know me by name. However that does have some advantages when it comes to warranties, pricing, info, etc. Competition in this market will likely help improve the product and keep the price down.

 

[Tim1023]

I think what’s most important to me is the proximity to my LBS, which happens to be Trek. Ive developed a relationship with them and unfortunately most of the reps and mechanics know me by name. However that does have some advantages when it comes to warranties, pricing, info, etc. Competition in this market will likely help improve the product and keep the price down.

That's one reason I would never buy an eMTB online. With a standard bike, you can do quite a lot without many specialist tools, but with the motors and control systems, you're pretty much buggered. My LBS is about 4.5 Km from home

 

[Stihldog]

That's one reason I would never buy an eMTB online. With a standard bike, you can do quite a lot without many specialist tools, but with the motors and control systems, you're pretty much buggered. My LBS is about 4.5 Km from home

My LBS is 4.6Km from home....not as lucky as you.
I remember that one of my concerns was whether my LBS could fix my motor WHEN it fails. I asked about their training, do they have the tools, parts in stock, how long would it take to fix, and a few others questions. I guess i needed those assurances before I took the leap. Most other things can easily be fixed by myself, but the motor....hmmm.

 

[routrax]

@Bearing Man might have a good idea on what is the best in terms of build quality.

 

[Bearing Man]

@Bearing Man might have a good idea on what is the best in terms of build quality.

He does know exactly what motor is best and worse...
The problem I have with this question, is that a bike should be bought with the heart and not the head. A bike should be bought because of its looks, its feel, its fit, etc...
If I tell people that one motor is slightly better built or slightly less reliable for some people than another motor, it may put them off buying that dream bike that they fall in love with and run and repair regardless of cost, because they love it so.
I think you can all see from the forums which motors are not doing well. But, don't forget, for every person that's had a problem, there are thousands who have had nothing but fun.
Trust me, if motors were as unreliable as you're lead to believe, I would be retiring soon... And I'm not! ?

 

[stiv674]

There are far too many variables to 'prove' which is the most reliable motor.

 

[Tim1023]

The problem I have with this question, is that a bike should be bought with the hart and not the head. A bike should be bought because of its looks, its feel, its fit, etc...

Makes me think of cars of yesteryear. Alphas that were beautiful, but rusted to bits in a few years. Or Lotus cars from the UK. They used to say the name stood for "Lots Of Trouble Usually Serious". Now that is buying with the heart and not the head!

 

[jimbob]

He does know exactly what motor is best and worse...
The problem I have with this question, is that a bike should be bought with the hart and not the head. A bike should be bought because of its looks, its feel, its fit, etc...
If I tell people that one motor is slightly better built or slightly less reliable for some people than another motor, it may put them off buying that dream bike that they fall in love with and run and repair regardless of cost, because they love it so.
I think you can all see from the forums which motors are not doing well. But, don't forget, for every person that's had a problem, there are thousands who have had nothing but fun.
Trust me, if motors were as unreliable as you're lead to believe, I would be retiring soon... And I'm not! ?

What a tease!

I think knowing something about the build quality is still an important factor when buying something so expensive. Its something I definitely took into consideration when choosing which bike to get.

 

[Bearing Man]

There are far too many variables to 'prove' which is the most reliable motor.

We tend to go on numbers so if for example there are 7 million "X" motors out there and 1.5 million "Y" motors out there, and we are repairing 2 "Y" motors to every "X" motor, it does not look good for the "Y" motor.

 

[JoeBlow]

There are far too many variables to 'prove' which is the most reliable motor.

What variables please explain? If one brand of motor can be shown to be more prone to failure that's the only variable required. This number should of course be taken over as many sources as possible but if I was a professional motor repair technician I'm sure I would soon develop a sense of which brand I was seeing more of and which ones I hardly saw at all. It's not scientific data analysis in the strictest sense of the word but it is still a strong indicator.

 

[Bearing Man]

What a tease!

I think knowing something about the build quality is still an important factor when buying something so expensive. Its something I definitely took into consideration when choosing which bike to get.

I agree, but they are all pretty good build quality these days, just some are designed better than others.

 

[Bearing Man]

What variables please explain? If one brand of motor can be shown to be more prone to failure that's the only variable required. This number should of course be taken over as many sources as possible but if I was a professional motor repair technician I'm sure I would soon develop a sense of which brand I was seeing more of and which ones I hardly saw at all. It's not scientific data analysis in the strictest sense of the word but it is still a strong indicator.

Exactly! Its like every time you drive up the motorway, if you always see the same make of car at the side of the road with the bonnet up, it gives you a good idea that it maybe a bad idea to by that car!

 

[stiv674]

How it's ridden
Where it's ridden
Weather conditions
How it's maintained
Distance covered and how hard it's been working

I'm happy to be proven wrong when this proof comes out

 

[stiv674]

We tend to go on numbers so if for example there are 7 million "X" motors out there and 1.5 million "Y" motors out there, and we are repairing 2 "Y" motors to every "X" motor, it does not look good for the "Y" motor.

If only we knew what X and Y stood for...

 

[Bearing Man]

How it's ridden
Where it's ridden
Weather conditions
How it's maintained
Distance covered and how hard it's been working

I'm happy to be proven wrong when this proof comes out

What is interesting, is that we are building up a pretty good picture of different terrains and temperatures now, so we have the usual wet issues from Norway, Finland, Wales etc. But also popular failure spots like California, Australia (Outback), Spain (desert regions) etc. So fine dust is a good leveler.
The how it's ridden does not seem to be an issue apart from pedal strikes.
How its maintained, again, not too much of an issue unless it's cleaned to much or in the case of Bosch Gen 2 motors, the dirt is left to build up behind the sprocket.
Bike design plays a big part, Trek, Haibike, Specialized etc. all have design flaws that can affect the motors.

 

[JoeBlow]

How it's ridden
Where it's ridden
Weather conditions
How it's maintained
Distance covered and how hard it's been working

I'm happy to be proven wrong when this proof comes out

I think you may be waiting a long time for that level of analysis. I'll stick with mine and Bearing Mans method in the meantime.

 

[stiv674]

I think you may be waiting a long time for that level of analysis. I'll stick with mine and Bearing Mans method in the meantime.

Which was sort of my point really I think most motors are pretty reliable anyway, there's always going to be some problems.

 

[jimbob]

What is interesting, is that we are building up a pretty good picture of different terrains and temperatures now, so we have the usual wet issues from Norway, Finland, Wales etc. But also popular failure spots like California, Australia (Outback), Spain (desert regions) etc. So fine dust is a good leveler.
The how it's ridden does not seem to be an issue apart from pedal strikes.
How its maintained, again, not too much of an issue unless it's cleaned to much or in the case of Bosch Gen 2 motors, the dirt is left to build up behind the sprocket.
Bike design plays a big part, Trek, Haibike, Specialized etc. all have design flaws that can affect the motors.

What would you say the main modes of failures are for the motors? I'm personally interested in the shimano E7000, but would be interesting for the others too.

 

[Dave_B]

my e7000 failed (E010) after I had owned the bike (ex demo) for a few weeks, replaced with a new motor.
a mate has a brand new, 1 month old e7000 bike and the speed sensor has failed (not sure how a wire can fail!).
So that's two Shimano motors that I have personally seen with issues. It's kind of why I asked the question.
Brose always get a bad comment re motor reliability.

but, I wonder what % of the ebike owning population post on forums? are we in the minority and hence become aware of the potential issues and worry too much? do the rest of the none forum posting population just crack on without any care? it tends to be a failure followed by a google search that brings people to the forums (certainly did in my case). lol, followed by me reading round most of the sections on this forum and thinking that all eBikes have motor issues !

 

[Flatslide]

I would posit a motor that does not have the bottom bracket as part of its construction - which appears to be a major factor in water ingress and puts all crank loading directly into the motor assembly, would be a candidate for the most reliable motor. There's one major brand that does this, if only I could think who they were...

 

[KeithR]

How it's ridden
Where it's ridden
Weather conditions
How it's maintained
Distance covered and how hard it's been working

Yep, and even that only pertains to a bike - nobody (not even Bearing Man, whose contributions I appreciate and respect immensely) can say with any confidence how many of a given motor have failed worldwide, making any attempt meaningfully to quantify relative motor reliability a fool's errand.

We're dealing with anecdotal evidence and (relatively) small samples in the case of Bearing Man - the manufacturers aren't saying - and nothing truly useful or statistically significant can be derived from those sources.

 

[JoeBlow]

my e7000 failed (E010) after I had owned the bike (ex demo) for a few weeks, replaced with a new motor.
a mate has a brand new, 1 month old e7000 bike and the speed sensor has failed (not sure how a wire can fail!).
So that's two Shimano motors that I have personally seen with issues. It's kind of why I asked the question.
Brose always get a bad comment re motor reliability.

but, I wonder what % of the ebike owning population post on forums? are we in the minority and hence become aware of the potential issues and worry too much? do the rest of the none forum posting population just crack on without any care? it tends to be a failure followed by a google search that brings people to the forums (certainly did in my case). lol, followed by me reading round most of the sections on this forum and thinking that all eBikes have motor issues !

When I was in the market for a new bike I asked 12 or so Levo owners what their experience had been. 7 said they had returned their bikes for motor replacements. I believe this was also around the time when Specialised extended their warranty to 4 years but only for a specific batch of bikes which to me seemed to be a tacit acknowledgement that there were issues and it put me off buying one.

 

[Bearing Man]

What would you say the main modes of failures are for the motors? I'm personally interested in the shimano E7000, but would be interesting for the others too.

Every motor has its own Achilles heal or week spot, for a small example:

Shimano, software issues, occasional cracked plastic drive gears, dirt ingress to open bearings just behind outer seals, electrolysis around electrical connectors.
Yamaha early, pcb failures, occasional stripped plastic drive gears (possible pedal strike failures) Water ingress
Yamaha late, PW-X plastic drive gear cracks, water ingress.
Bosch Gen 1, drive gear failure. Water ingress.
Bosch Gen 2, Main motor bearing. Water ingress
Bosch Gen 3, Ceramic seal failure. Water ingress
Bosch Gen 4 early, Overheating issues or faults.
Brose 1.2 Sprag bearing failure, occasional belt failure, water ingress etc.
Brose 1.3 Sprag bearing failure, occasional belt failure, water ingress etc.
Brose 2.1 Sprag bearing failure, occasional belt failure, occasional crankshaft failure water ingress etc.
Brose 2.1 2021 Water ingress.
Impulse 1.0 2.0 and EVO ST Freewheel ratchet and pawl mechanism failure, small drive gear bearing failure, torque sensor and ECU failure, water ingress.

Obviously we see many more issues from time to time in these motors but listed are some of the main failure points.

 

[stiv674]

@Bearing Man Seeing as my Shimano e8000 will soon be out of warranty, how serviceable is it? Apart from the bottom bracket issue, are there other things to look out for?

 

[TPEHAK]

According my local e-bike dealer who sells e-bikes equipped with Bosch and Yamaha motors Yamaha motors are the most reliable ebike motors. All clients motor related returns and complaints are about Bosch motors and they have zero Yamaha motor related issues.

 

[Bearing Man]

@Bearing Man Seeing as my Shimano e8000 will soon be out of warranty, how serviceable is it? Apart from the bottom bracket issue, are there other things to look out for?

The E8000 is serviceable, less one bearing that still requires manufacture but we won't be supporting this motor I am sorry to say.