Known Issues & Problems with Brose Products + Help, Solutions & Fixes

Thank your for providing this forum to discuss Brose Motors.

I recently wrote a piece about the first 9 months / 5000 miles on my Specialized Vado 5.0 which houses a Brose 1.2s Motor (TF C97292 according to your write up above). You can see it here on EBR. An excerpt from that entry is below:

The Brose motor has now been replaced 3 times. Should you buy this bike, buy it from a shop with excellent service. I bought mine from Cynergy. Cynergy has given me bike loaners while my bike is being repaired which has been awesome. I unfortunately anticipate replacing this motor every 3 months. The 2 year warranty has covered the repair each time. The best (and lackluster) advice I got from Specialized is to not mash my gears and to downshift when approaching a stop. I rarely mash my gears and always downshift. I have recently begun downshift 7-9 gears to determine if this make a difference. Any insight to this would be appreciated. Brose are you listening? I would love to hear from you....
Specialized via Cynergy has replaced the brose motor each time it has failed. I've been told by Cynergy, that these failures are of great concern to Specialized. The motor has failed at about 2000 miles each time. Though I have not heard anything specific from Brose or Specialized about the motor failures, I will continue to inquire about the nature of the motor failure as I estimate I will be receiving 4 more motors before the warranty is up and would like to avoid this, especially when the warranty is up. This is one reason I'm reaching out to the EBR network and others in the industry.

Current theories on my thread mention my size and riding style. I spoke to the manager at Cynergy about this a while ago and he assured me that my size and style of riding are accommodated by Specialized Designers. Another EBR member mentioned I'm likely overheating the motor and that I should test it with laser temp. Thoughts on laser temp? I used my hand this morning and did not feel any warmth near the motor this morning. Should you or anyone else have insight into why the Brose motor has failed 3 times on my Specialized Vado 5.0, I would appreciate it.

A bike mechanic recently told me I needed to replace the chain ring. In a previous conversation with that same mechanic I asked whether I could increase the chain ring size to decrease the wear on the cassette or at least the wear on the 11t and 13t cog. The mechanic thought I would disrupt the motor, but now I'm wondering if I should revisit that discussion. Has anyone increased the chain ring size on their OEM bike with a Brose motor?

Any questions, let me know

Thanks.
Hey 2weels.. I have an EVO 45 Bulls bicycle 2017 with the Bros motor and I am on my Fifth Motor with the exact same symptoms of a high whining noise and no motor assist!!! This motor failure has nothing to do with downshifting or chainring size . The motor is failing about every 2500 miles which is on every three months for me. This is definitely a design issue. Let me know if you hear anything from specialized about Bros implementing fix or a recall. I'm not getting much information from Bulls although they're replacing the motor with a four to six-week turn around . ☹️☹️☹️☹️
Email directly if you can with any new information [email protected]
 
I was talking to a salesrep at an online Ebike retailer about this issue. He told me they've seen two Bulls Evos have the recurring motor failure issue. In both, the rider/owners had e-tuned their bikes and admitted such to their tech. He said they always try to support their customers, so have worked with Bulls to replace the motors(5 motors over a year between the two bikes).

He said he's sold dozens of Bulls without problem and found it more than coincidental that the two repeat failure customers were both probably using their brose engines beyond the specified operating parameters.
 
Last edited:
I was talking to a salesrep at an online Ebike retailer about this issue. He told me they've seen two Bulls Evos have the recurring motor failure issue. In both, the rider/owners had e-tuned their bikes and admitted such to their tech. He said they always try to support their customers, so have worked with Bulls to replace the motors(5 motors over a year between the two bikes).

He said he's sold dozens of Bulls without problem and found it more than coincidental that the two repear failure customers were both probably using their brose engines beyond the specified operating parameters.
So did they use speedbox or something similar?



My Bulls e stream Evo 45 bike is a class 3 which goes 30 miles an hour and basically it's difficult to ride this thing anything beyond its designed ability. As for only a couple customers having this issue how many people actually ride their bike 900 miles to 1200 miles in one month because I do every month.. it may take people 2-3years to put that many miles on their bicycle. My biggest issue is that Bros and both give you no information as to the nature of the failure and since I'm not allowed to open the motor because of a void the warranty I cannot tell if it's the planetary gear system that his family or the belt. And I am told that there is not an option to purchase a belt and repair yourself which I have viewed the video on BMZ website and it's a simple fix but without the belt it's impossible fix. Both tells me that $225 out of warranty fix with a $50 shipping charge
 
My Bulls e stream Evo 45 bike is a class 3 which goes 30 miles an hour and basically it's difficult to ride this thing anything beyond its designed ability. As for only a couple customers having this issue how many people actually ride their bike 900 miles to 1200 miles in one month because I do every month.. it may take people 2-3years to put that many miles on their bicycle. My biggest issue is that Bros and both give you no information as to the nature of the failure and since I'm not allowed to open the motor because of a void the warranty I cannot tell if it's the planetary gear system that his family or the belt. And I am told that there is not an option to purchase a belt and repair yourself which I have viewed the video on BMZ website and it's a simple fix but without the belt it's impossible fix. Both tells me that $225 out of warranty fix with a $50 shipping charge
Ok, you've got a lot of typos in your post, so Im a little confused. The Brose is supposed to be good for 15,000km before any service is necessary, so I guess that's annually for you.

I think your Brose TF is rare enough where most of us here will be talking about the T motor and less commonly, the S motor. I dont think there are very many people delimiting a 28mph bicycle to try and hit 35 or 40mph assisted! ? The Brose S and TF look almost exactly the same on the spec sheets except for hardware. Has anybody considered that maybe traveling at 25 or 28 mph for extended periods is beyond what these things can handle?

Once youre out of warranty, there are a lot of places to get . Check with performancelinebearings.com. They stock most of the standard parts for the Brose motors and I know they have manufactured almost all of the proprietary parts too. Shouldnt be to expensive or time consuming to change the belt on your own.
 
Ok, you've got a lot of typos in your post, so Im a little confused. The Brose is supposed to be good for 15,000km before any service is necessary, so I guess that's annually for you.

I think your Brose TF is rare enough where most of us here will be talking about the T motor and less commonly, the S motor. I dont think there are very many people delimiting a 28mph bicycle to try and hit 35 or 40mph assisted! ? The Brose S and TF look almost exactly the same on the spec sheets except for hardware. Has anybody considered that maybe traveling at 25 or 28 mph for extended periods is beyond what these things can handle?

Once youre out of warranty, there are a lot of places to get . Check with performancelinebearings.com. They stock most of the standard parts for the Brose motors and I know they have manufactured almost all of the proprietary parts too. Shouldnt be to expensive or time consuming to change the belt on your own.
Pardon the typos. Thanks for the information on where to get parts for the brose motor. I have watched the video on bmz to change the belt it's a simple procedure I just didn't know where to get the belt since Bros was not offering an opportunity to purchase it.

Thanks Clifford
 
All these issues are making me rethink my initial preference for Brose. I haven't bought a bike yet, but am planning to in the next year or so. I test rode bikes with Bosch, Brose, and Shimano systems. Brose was by far my favorite because it seemed most similar to a conventional bike; very natural. The other two were fine, and I liked Shimano almost as much. While Bosch work fine it just didn't feel very natural to me, but I'd probably get used to it.
 
Last edited:
All these issues are making me rethink my initial preference for Brose. I haven't bought a bike yet, but am planning to in the next year or so. I test road bikes with Bosch, Brose, and Shimano systems. Brose was by far my favorite because it seemed most similar to a conventional bike; very natural. The other two were fine, and I liked Shimano almost as much. While Bosch work fine it just didn't feel very natural to me, but I'd probably get used to it.
My sentiments exactly, Brose is the most "natural" feeling (and quietest), Shimano a close second, then Yamaha, then Bosch. Bosch is also the noisiest by far.
 
My sentiments exactly, Brose is the most "natural" feeling (and quietest), Shimano a close second, then Yamaha, then Bosch. Bosch is also the noisiest by far.

Maybe that's why Brose systems are less reliable. Bosch systems are noisy and heavy, but seem more reliable. Shimano seems to strike a nice balance. They're a little heavier than Brose, lighter than Bosch, but still seem fairly reliable from what I've gathered.

While I'm inclined to get a mid-drive e-bike I'm not committed to it. I certainly like their versatility and greatly increased range, but there's also a compelling argument for the simplicity and lower cost of conventional bikes.

I view cycling primarily as transportation while exercise is secondary. I'd rather ride to a trail-head and have more energy for hiking or running so I probably will get an e-bike.
 
Maybe that's why Brose systems are less reliable. Bosch systems are noisy and heavy, but seem more reliable. Shimano seems to strike a nice balance. They're a little heavier than Brose, lighter than Bosch, but still seem fairly reliable from what I've gathered.

While I'm inclined to get a mid-drive e-bike I'm not committed to it. I certainly like their versatility and greatly increased range, but there's also a compelling argument for the simplicity and lower cost of conventional bikes.

I view cycling primarily as transportation while exercise is secondary. I'd rather ride to a trail-head and have more energy for hiking or running so I probably will get an e-bike.
Knock wood, my Bulls w/Brose has had zero problems in 2 years and 1500+ hardy trail miles with LOTS of steep climbing. I've actually heard more stories about bearing failures with Bosch systems than problems with any other major mid-drive makers' motors, but Bosch has a lot more out there.

After 4 years and several thousand combined miles on multiple ebikes (including a few hub-driven models like Rad, BH/EasyMotion etc.), I'm way partial to mid-drives, especially for off-road use. If your rides are likely to be on pavement at higher speeds with minimal steepness to surmount, a hub motor may be better suited for you.

Your simplicity is my complexity, however: changing flats on hub-motor models is considerably more challenging than on mid-drives, for one thing. And because 90% of my cycling is on technical trails, the balance and low-speed efficiency offered by mid-drives is worth the higher costs...
 
... After 4 years and several thousand combined miles on multiple ebikes (including a few hub-driven models like Rad, BH/EasyMotion etc.), I'm way partial to mid-drives, especially for off-road use. If your rides are likely to be on pavement at higher speeds with minimal steepness to surmount, a hub motor may be better suited for you.

Your simplicity is my complexity, however: changing flats on hub-motor models is considerably more challenging than on mid-drives, for one thing. And because 90% of my cycling is on technical trails, the balance and low-speed efficiency offered by mid-drives is worth the higher costs...
I also strongly prefer mid-drive motors for their lightness and more natural feel. I like that mid-drives function very much like enhanced conventional bikes. I mainly want an e-bike for better efficiency (speed) on hills. I don't mind working hard on hills, but there's a huge practical difference between an average speed of 5 mph (conventional bike) and 25 mph (mid-drive e-bike).
 
I tried several e-bikes and own few too. I live in a hilly area and mid-drives are best choice hands down. Earlier Brose models had some issues but new ones seem to be very good. They aren't as fast as Yamaha but they are very quiet and smooth and handle hills with charm.

IF brose can solve that acceleration problem I think they will be my #1 choice for mid-drive systems.
 
I tried several e-bikes and own few too. I live in a hilly area and mid-drives are best choice hands down. Earlier Brose models had some issues but new ones seem to be very good. They aren't as fast as Yamaha but they are very quiet and smooth and handle hills with charm.

IF brose can solve that acceleration problem I think they will be my #1 choice for mid-drive systems.
My LBS is an excellent wrench and a Raleigh dealer. He told me the major issue with Brose motors is diagnosing problems. He said some issues can't be easily identified and the motor must be removed from the bike and shipped to a regional distributor for repair. Bosch and Shimano problems are identified with diagnostic software at a local dealership who can usually fix it.

He told me for now Raleigh has stopped using Brose motors for this reason; it's easier for them and customers to have a system that can usually be serviced locally. He told me Brose is in the process of developing their system to be more locally repairable. I hope so because they are my favorite of the three I've tried.
 
My Bulls e stream Evo 45 bike is a class 3 which goes 30 miles an hour and basically it's difficult to ride this thing anything beyond its designed ability. As for only a couple customers having this issue how many people actually ride their bike 900 miles to 1200 miles in one month because I do every month.. it may take people 2-3years to put that many miles on their bicycle. My biggest issue is that Bros and both give you no information as to the nature of the failure and since I'm not allowed to open the motor because of a void the warranty I cannot tell if it's the planetary gear system that his family or the belt. And I am told that there is not an option to purchase a belt and repair yourself which I have viewed the video on BMZ website and it's a simple fix but without the belt it's impossible fix. Both tells me that $225 out of warranty fix with a $50 shipping charge
Sorry for the long time before my reply. I was emailing with my online ebike salesrep. He told me he thought the Bulls Evo's Brose motor powered the bike to something closer to a top speed of 27mph. He said when people use a dongle, they're often asking the brose motor to give assistance up to the limits of human endurance, which can sometimes even be 40mph. In any event, he wasnt providing science or conclusive product max specs, but just giving antidotal feedback based on the small number of brose failures he's seen.
 
No ebike is perfect, this is a thread dedicated to sharing known issues or problems with electric mid drive motors from Brose as well as any help and solutions you know of. Sometimes that means a DIY fix and other times it can mean a recall, software update or part replacement by a dealer.

Please be respectful and constructive with feedback, this is not a space for hate speech. In many cases, representatives from the company will see feedback and use it to improve their product. In the end, the goal is to enjoy riding and help each other go further and be safer.


Brose Forum

I just recently bought the Specialized Turbo Como 5 and from day 1 have experienced what feels like power fluctuations in the motor. I also have a Como 2 with no such issues. The Como 2 has been smooth sailing. On the 5 however, with the Brose S motor (Specialized 1.3), it feels like I lose power for just a second, then back to normal, then lose power, etc. It's just a feeling of the power fluctuating the entire ride. Also, it doeHas anyone else had this issue? If so, what was the fix? I'll be taking the bike back to the shop to have this looked at soon, but right now the weather here is so great that I have decided to just live with it until I can get it back to my lbs.
 
Brose Forum

I just recently bought the Specialized Turbo Como 5 and from day 1 have experienced what feels like power fluctuations in the motor. I also have a Como 2 with no such issues. The Como 2 has been smooth sailing. On the 5 however, with the Brose S motor (Specialized 1.3), it feels like I lose power for just a second, then back to normal, then lose power, etc. It's just a feeling of the power fluctuating the entire ride. Also, it doeHas anyone else had this issue? If so, what was the fix? I'll be taking the bike back to the shop to have this looked at soon, but right now the weather here is so great that I have decided to just live with it until I can get it back to my lbs.
Don't know it this well help, but when my cadence drops low the motor will cut off/on. Also, you might give your LBS a call to check with them and, if you have "Mission Control" on your Como 5, the LBS maybe able to instruct you in how to adjust the motor settings to alleviate the problem.

gl
 
Thanks so much. All suggestions are appreciated! Cadence doesn't seem to be the issue, however, even at low cadence these power fluctuations should not be happening. This is my 9th ebike. My bad knees have required me to use ebikes, and I have been blessed to have owned some very nice ebikes. I've had 3 Trek, 4 Felt (mountain and road versions), and now 2 Specialized. I've ridden Shimano Steps, Bosch, and now Brose. Never had any problems at all with the Bosch. Very reliable. Yes, it is louder, but really it is still hardly noticeable. I wanted the Specialized Como because I love the look, the upright fit, (which at my age has now become a big deal) , and I loved the advertised torque on the Brose S and the extended battery on the Como 5. The bike is sitting at my lbs right now. I have yet to really enjoy it, and I am beginning to wonder if I've made a mistake. I also worry that my lbs is out of their element on this. They have only really just very recently embraced the ebike scenario, and I'm pretty sure I might be their very first motor problem.
Also, now on my Como 2, which I have only put 150 miles on it, is having problems. When I go to turn on the power it will not come on. The green lights will light up on the battery, the display will light up, but the display will not come fully on, rather it flickers. It's as if it tries to come on or boot up and never quite gets there. If I turn the power off and on a few times it will finally start up. Now I am worried about this issue too! I would hate to have both Como's in the shop. Also, the battery wants to pop out. This morning I went to remove the charger from the battery and when I pulled on the magnetic rosenberg plug the battery pulled out to the side?!! What?!! I've never ever even removed the battery. It's only been ridden on pavement, and I may have hit a few potholes, but none of them were particularly big. That shouldn't happen either!
 
Also, now on my Como 2, which I have only put 150 miles on it, is having problems. When I go to turn on the power it will not come on. The green lights will light up on the battery, the display will light up, but the display will not come fully on, rather it flickers. It's as if it tries to come on or boot up and never quite gets there. If I turn the power off and on a few times it will finally start up. Now I am worried about this issue too! I would hate to have both Como's in the shop. Also, the battery wants to pop out. This morning I went to remove the charger from the battery and when I pulled on the magnetic rosenberg plug the battery pulled out to the side?!! What?!! I've never ever even removed the battery. It's only been ridden on pavement, and I may have hit a few potholes, but none of them were particularly big. That shouldn't happen either!

The battery ”fixation” ( sorry can’t come up with a better word) is a kind of problem on the Vado and Como since they first came out. Specialized tried to fix it with som kind of shim to make the battery stay firmly. You have to give the battery a really firm press to seat properly. If that is done they seem to stay in place.

Maybe your starting problem on the Como 2 is related to battery not properly fixed?

Last week my LBS turned the battery key ( on my Vado 5.0) by mistake and turned back to lock position again and all seemed fine. A day later I noticed I had some rattling noise and thought it was something in my handlebar bag ( keys, tools) but it was the battery not fully fastened. Needed a distinct firm press to get it seated. No problems after that.
Had a Vado 4.0 last year and took out the battery a few times as I had to carry the bike up to my apartement ( elevator failure) and it was not easy to get the battery back but it never came loose.
 
Videos (one Court's) on Vado/Como operation suggest after hearing battery click into place, give the battery a firm slap to assure it has fully seated. Before I doing this on my Vado I would have occasional motor cuts outs, as if the battery had giggle room.
 
Back