Brose S and T overhaul video done at last!

[Bearing Man]

Sorry its taken so long but for those who asked we have delivered, and what an example we found to repair!

 

[Mina08]

Top Vid thank you. are you offering service by mail order?

 

[Max-E]

Truly awesome.

I'd just maybe say (for your benefit and new customers!) add 'Specialized Levo Brose Motor Bearings' or similar to the Youtube title as much more likely to be found in a search.

 

[Troutwrestler]

Could you get an engineering workshop to remanufacture the axles or re-sleeve the bearing surface?

 

[Webike]

Thank you for the great tutorial! You make a complicated process seem doable but the large majority of the population would be unable to do this since it requires such special tooling to complete, let alone the years of mechanical knowledge & practice required to avoid the potential assembly errors. Having worked on myriad motors, machines & assorted mechanical devices I would prefer to send my motors to you for the rebuild & not attempt the "Beta" testing this process involves. It's good to know that there is someone out there who is so knowledgeable about the Brose motor systems. Thanks again.

BTW, do you have an educated guess as to what causes the motor whine noise, especially when the motor itself is over 110 degrees Fahrenheit, and is it related to the belt tension or tensioner assembly? Also, do you know how Brose reduced most of the motor noise issues related to the first release of the 2019 Levo models?

 

[Kiwi in Wales]

Hi @Bearing Man
Great video!

There is obviously a water ingress problem with the Brose motor and I presume it is quite possible it may be the same for some of the other manufacturers ebike motors that you have recently had apart.

It would be really interesting to get some feedback from you regarding which ones you think are currently the worst offenders?

Also, regarding the Brose motor you worked on in this video and your hands on experience with pulling it apart. Can you confirm where you think the water is actually getting in?

Moving forward, are there any tips you can suggest to try and keep the water from getting in?

I guess pulling the motor apart every few weeks and regreasing all the bearings ‘may’ help and this would be okay on a motor over 2 years old but doing this maintenance would surely need to be done from when the bike was new and not after 2 years in the wild. However, doing this work on a new ebike would, as you know, void the warranty

Looking forward to your feedback.

 

[Bearing Man]

Top Vid thank you. are you offering service by mail order?

Yes, we do this for all motors, Brose, Bosch, Yamaha etc. It works well.

 

[Bearing Man]

Truly awesome.

I'd just maybe say (for your benefit and new customers!) add 'Specialized Levo Brose Motor Bearings' or similar to the Youtube title as much more likely to be found in a search.

Thank you Max-E, already in the tags

 

[Bearing Man]

Could you get an engineering workshop to remanufacture the axles or re-sleeve the bearing surface?

We may have to when we run out of good parts!

 

[Bearing Man]

Thank you for the great tutorial! You make a complicated process seem doable but the large majority of the population would be unable to do this since it requires such special tooling to complete, let alone the years of mechanical knowledge & practice required to avoid the potential assembly errors. Having worked on myriad motors, machines & assorted mechanical devices I would prefer to send my motors to you for the rebuild & not attempt the "Beta" testing this process involves. It's good to know that there is someone out there who is so knowledgeable about the Brose motor systems. Thanks again.

BTW, do you have an educated guess as to what causes the motor whine noise, especially when the motor itself is over 110 degrees Fahrenheit, and is it related to the belt tension or tensioner assembly? Also, do you know how Brose reduced most of the motor noise issues related to the first release of the 2019 Levo models?

Motor whine noise in a Brose motor is almost always to do with belt tension. The surface area of the pulley gears is massive compared to the belt, so even a small expansion here will alter the belt tension by quite a bit.
Not seen a 2019 motor yet as they are all still in warranty, so can't answer that one

 

[Bearing Man]

Hi @Bearing Man
Great video!

There is obviously a water ingress problem with the Brose motor and I presume it is quite possible it may be the same for some of the other manufacturers ebike motors that you have recently had apart.

It would be really interesting to get some feedback from you regarding which ones you think are currently the worst offenders?

Also, regarding the Brose motor you worked on in this video and your hands on experience with pulling it apart. Can you confirm where you think the water is actually getting in?

Moving forward, are there any tips you can suggest to try and keep the water from getting in?

I guess pulling the motor apart every few weeks and regreasing all the bearings ‘may’ help and this would be okay on a motor over 2 years old but doing this maintenance would surely need to be done from when the bike was new and not after 2 years in the wild. However, doing this work on a new ebike would, as you know, void the warranty

Looking forward to your feedback.

Don't panic, there is not a water ingress problem with the Brose motors, in fact they are one of the better sealed motors.
The motor in the video had been pressure washed. There is not a motor on the market that will keep 1,000psi of water out! But your question is a good one. When we rebuild any motor, we grease the outer bearing surface with bike grease 2000, before the bearing is fitted back into the case. This packs the gap between the bearing and the case to stop water sitting in there. We also smear the outer bearing seals with the same grease to delay water/dirt ingress. With Brose and Yamaha motors we syringe this grease between the crankshaft and sprocket carrier. All these little things make a big difference over time.

 

[Bearing Man]

You guys maybe able to help here, I didn't know if this was the best thread to post this on? If you could share with other threads you think maybe interested, like Levo owners thread etc? Thank you.

 

[Al Boneta]

Specialized offers a “Crash” replacement for a motor that is out of warranty. It’s a reconditioned motor, but it has a two year warranty. Cost is up to the shop, but I charge $650 installed.

 

[Bearing Man]

Specialized offers a “Crash” replacement for a motor that is out of warranty. It’s a reconditioned motor, but it has a two year warranty. Cost is up to the shop, but I charge $650 installed.

Wow! I'm way to cheap!

 

[Al Boneta]

Wow! I'm way to cheap!

For the amount of work you do in that video I would say so. If you can’t save the motor because of the destroyed bearing surfaces on parts that cannot be replaced do you still get a fee for diagnosis? If you don’t you should.

 

[Webike]

Motor whine noise in a Brose motor is almost always to do with belt tension. The surface area of the pulley gears is massive compared to the belt, so even a small expansion here will alter the belt tension by quite a bit.
Not seen a 2019 motor yet as they are all still in warranty, so can't answer that one

Do you know if the whine noise is caused by the belt being too tight and therefore the original adjustment was set too high? By the way I'm jealous of your shop set up and the array of specific tools...gotta get me one of those torque adjusting screwdrivers. 0.25 to 0.3 Nm +\-

 

[scoobysteve]

great video, very informative. with regards to damaged crankshafts where the bearing surface is pitted have you looked into turning the diameter down, welding the material up then getting it re ground to the correct diameter and to a perfect finish before heat treating it to case harden it? could be an option so you could have a supply of spares if brose are unwilling to supply new crankshafts. with the rise in popularity of bikes I'm sure you're going to be busy for a long time! regards, Steve.

 

[Zimmerframe]

Motor whine noise in a Brose motor is almost always to do with belt tension.

This thread needs a bump ... I missed it first time round and it's very interesting ! Thanks for making the video.

A quick question for those with the whine - can they adjust that when the motor is still on the bike ? (you loosen it at the start of the video) and should they loosen it or tighten it ?

EDIT : the tension setting is confirmed at 32:30 minutes in the video

I did have lots of other questions .. but they've all been answered reading the thread !

 

[Bearing Man]

A quick question for those with the whine - can they adjust that when the motor is still on the bike ? (you loosen it at the start of the video) and should they loosen it or tighten it ?

The belt tension screw should be left well alone unless you have the right tool. The torque setting is critical. Some bikes it is accessable, but most it is not unless the motor is removed.

 

[Webike]

A quick question for those with the whine - can they adjust that when the motor is still on the bike ? (you loosen it at the start of the video) and should they loosen it or tighten it ?

For better or for worse, the adjustment screw is on top of the motor and requires removal of the motor for access unless you want to guess at the screws location and drill a hole thru the frame motor housing...not suggested. The special torque screwdriver is a pricey little item at over $100 and the potential Loc-tite on the threads of the adjustment screw could alter the torque reading. Not sure if the screw can be removed, threads cleaned, new Loc-tite applied then adjust to the specification but this procedure would be risky for those with bikes still under warranty and not advised.

Per Bearing Man:
"Motor whine noise in a Brose motor is almost always to do with belt tension. The surface area of the pulley gears is massive compared to the belt, so even a small expansion here will alter the belt tension by quite a bit."

Does this mean the pulley increases in circumference thereby increasing belt tension? If that is the case then would backing off on the belt tension reduce the whine? As you can see in his video the belt adjustment seems quite finite so small adjustments increments could have a dramatic effect and the process of removing the motor, adjusting the tension, reinstallling the motor then testing could be an arduous chore...best left to the professionals or nerds like myself who have time on their hands. Maybe after the warranty expires.

 

[Bearing Man]

Per Bearing Man:
"Motor whine noise in a Brose motor is almost always to do with belt tension. The surface area of the pulley gears is massive compared to the belt, so even a small expansion here will alter the belt tension by quite a bit."

Does this mean the pulley increases in circumference thereby increasing belt tension? If that is the case then would backing off on the belt tension reduce the whine? As you can see in his video the belt adjustment seems quite finite so small adjustments increments could have a dramatic effect and the process of removing the motor, adjusting the tension, reinstallling the motor then testing could be an arduous chore...best left to the professionals or nerds like myself who have time on their hands. Maybe after the warranty expires.

The belt tension is already very low, backing it off even further could result in the belt slipping (jumping teeth). The belt is factory set to be quiet when hot or cold, and therefore should not need to be "experimented" with. Along with belts you also have bearings and gears that can whine. Personally, unless you are absolutely sure what is causing the noise, I would highly recommend proceeding with caution!

 

[Bearing Man]

great video, very informative. with regards to damaged crankshafts where the bearing surface is pitted have you looked into turning the diameter down, welding the material up then getting it re ground to the correct diameter and to a perfect finish before heat treating it to case harden it? could be an option so you could have a supply of spares if brose are unwilling to supply new crankshafts. with the rise in popularity of bikes I'm sure you're going to be busy for a long time! regards, Steve.

I have looked at re-sleeving, and/or welding these cranks. Because of the low numbers we are talking about, currently, the cost is prohibitive.

 

[Mikerb]

Using heavy pressure on the cranks with low motor assist settings is a good way to stress everything in the motor! If you are applying heavy pressure to the cranks you are not in the right gear or using the motor as it has been designed. The whole point of an emtb is that heavy crank pressure is matched by motor assist levels.

 

[seamarsh]

Sorry its taken so long but for those who asked we have delivered, and what an example we found to repair!

Awesome video! I dont even own an e-bike yet but watched it.

 

[Rich the gasman]

What a great video.