Wait…I thought I was special.Just in case you didn't realise, I am Peter, owner of the eBike Motor Centre. Sorry, we didn't realise you were an EMTB Forum member when you called. We do have a few parts put by for special people
Oh well …
"2nd dead bosch gen 4 motor not happy
- Thread starter Geeman
- Start date
Oh well …
Paulquattro
E*POWAH Elite
Maybe a different kind of special LOLWait…I thought I was special.
Oh well …
Thanks Peter! Talked with you on 5th May then called back on 7th June and talked with David. And yes, I am "special" because my wife says so and she's always right. Sometimes!Just in case you didn't realise, I am Peter, owner of the eBike Motor Centre
Will call you then bring the two 2022 Rail 5's sometime after 15th July when it's convenient for you.
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Alright, just gimme a couple of days until I can see straight enough to fill in the form
Same here pal i have to usually wait till Monday to get everything back in focus after the Saturday.Alright, just gimme a couple of days until I can see straight enough to fill in the form
Yikes! I just got a new bike with a Bosch motor and this is the first thread I see. 
Don't lose faith just yet, they're not all this bad! There are thousands of people out there riding around on high mileage motors and no problems at allYikes! I just got a new bike with a Bosch motor and this is the first thread I see.
Hi Pete, can you outline what parts you are using for the upgrade? Have you found a way to fit 2 seals for 1 or is it just better seals? Are you using corrosion proof bearings SS/ceramic? What is the current situation with faulty circuit boards?Don't lose faith just yet, they're not all this bad! There are thousands of people out there riding around on high mileage motors and no problems at all
I think you sent your motor to us in the nick of time Bones! I hope you don't mind us sharing our findings on the forum, but I think those on this thread will find it interesting.
You reported your motor had a slight whine, but apart from that, felt good. This is a very typical and common statement by many people who send their motors to us, but hopefully the photos we took of your motor will show the importance of being very in tune with your motor and knowing what to look and listen for.
The picture below shows inside the drive side motor cover, the right hand crankshaft bearing and smaller transfer gear support bearing. The right hand crankshaft bearing is seized solid (this often happens when working motors are sent in with residual water left in the bearings). The light grey discolouration of the grease around the outside of the dark grease is caused by water emulsifying with the grease. The dark colouration is some sort of contamination, almost like a Moly grease? Or chain lube? The dryer consistency of this grease in the centre, by the bearing is caused by dirt contamination from within the bearing itself.
The picture below shows what's left of seal inside of the freewheel sleeve that fits through the right hand crankshaft bearing and supports the chainring spider. (No, it should not have all that dirt in it). The plastic bush below the seal was quite badly worn.
You can see the rust damage on the bearing surface of the crankshaft below. The crankshaft fits through the freewheel sleeve above and the damage to the crankshaft is why the plastic bushes don't last 5 minutes! It also gives you a clue as to how the water gets into a Gen 4.
Looking at the other end of the crankshaft below, it shows where the cadence cage (or black plastic bit) sits against the left hand crankshaft bearing. The rusty looking grease is from the left hand crankshaft bearing.
This is the left hand crankshaft bearing below and the main reason these fail, is because Bosch have fitted a metal shielded bearing. Meaning the bearing does not have a seal on the in side! Basically, the water runs down the crankshaft from the right hand freewheel sleeve seal and straight into the bearing.
The transfer gear cluster and armature below should look clean, and the grease should be a nice light tan colour. Unfortunately this is far from that and all the bearings where rough and worn. This is where the whining noise was coming from.
The drive gear below had transferred the debris and dirt from the right hand crank bearing and cover to the transfer gear cluster.
The printed circuit board (PCB) that sits around the crankshaft shows water damage and dirt/mud spots on it. This damage has come from the water and dirt dripping from the crankshaft ingress again. Once cleaned, dried and treated, this PCB actually still worked but was about as close as they come to killing the motor completely.
When 'Bones' motor arrived, it had several unusual fault codes which are usually a sign of a wet motor. The codes are caused when beads of water or droplets of dirt get onto the PCB, bridge out between components, then dry out and often the code will disappear. If this water bridges something important, that's usually the end of your motor. Bones has been a very lucky boy!
Please note: This motor had definitely not been pressure washed or showed signs of any abuse what so ever. It just shows that there is a very serous issue here. We tried to warn Bosch this was coming but after a reasonable meeting we were subsequently ignored. This is why we have put the effort into getting a solution made.
Wow that looks a mess Peter!.
Seems like I wasted my time with the seal kit a few months back
Great pictures and diagnosis.
Do I need to sell the family jewellery?
Like you say it's never been pressure washed but it's been through plenty of water crossings.
It is an MTB that gets some stick and we are in the UK
Have PM'd you @BonesWow that looks a mess Peter!.
Seems like I wasted my time with the seal kit a few months back
Great pictures and diagnosis.
Do I need to sell the family jewellery?
Like you say it's never been pressure washed but it's been through plenty of water crossings.
It is an MTB that gets some stick and we are in the UK
Wow, that's a shocker, amazing that motor still ran!Have PM'd you @Bones
That was a clean one, we see a lot worse!Wow, that's a shocker, amazing that motor still ran!
RyanP123
New Member
Should I be concerned about purchasing a new whyte e160 rsx? have had enough issues with my gen 1 levo so would like to avoid that again if possible 
Might not have been ignored, they might simply not want to give anyone else credit for the improved sealing on the next motor model (rumored to be released shortly)
THANK YOU FOR POSTING THE PHOTOS.... NOW I CAN BE ALMOST CERTAIN THAT MY ENGINE HAS ALSO BEEN BREAK DOWN THIS WAY
IN MY PHOTO YOU CAN SEE A BROWN EDGE AROUND THE BEARING (LEFT SIDE BEARING) THIS BROWN EDGE WAS THERE FOR A FEW HUNDRED KM UNTIL IT WON'T START (WITHOUT AN ERROR CODE...) IN YOUR PHOTO IT APPEARS THAT
IT APPEARS THAT THE PAINT LAYER IS COMING LOOSE THROUGH THE WATER
WHICH MAY CAUSE CLOSURE
SORRY FOR THE BAD TRANSLATION VANUIT HET NEDRLANDS
Plummet
Flash Git
My motor died last week. 11 months, 3000km. I've ridden some pretty harsh conditions. So assuming water ingress.
Let's see what happens
In the mean time I'm back on the mtb, which doesn't bother me as I'm mtbing 50% of the time anyway.
Let's see what happens
In the mean time I'm back on the mtb, which doesn't bother me as I'm mtbing 50% of the time anyway.
Was the motor noisy/whining before it died?
My bosch CX is has developed a noticeable whine recently - started carrying a tow rope so the dog can get me home
Plummet
Flash Git
N
Not overly, just started cutting out and getting all jittery before it cut out to a point where I called it and took it into the shop. Still waiting on the diagnostic from the bike shop.Was the motor noisy/whining before it died?
My bosch CX is has developed a noticeable whine recently - started carrying a tow rope so the dog can get me home
This is normally caused by rust (corrosion) coming out of the bearing.
Just got email from LBS that I`ll get new motor with 50% discount, so it`s about 500€ with labour. I`m happy with it. It`s my commuter, Focus Aventura 11k km on the clock. 4000km and one year first CX4 died and now after two years and 7000km after that, the second motor dies. So the motors lasted together little over three years. No mechanical failure, electronics. Now I get new motor with 2 years warranty First time when it was replaced under warranty, it took five weeks, this time about two months . Specialized was replaced in 1 1/2 weeks, free of charge even it was out of warranty
First time when it was replaced under warranty, it took five weeks, this time about two months . Specialized was replaced in 1 1/2 weeks, free of charge even it was out of warranty 
JP-NZ
E*POWAH Elite
Do you deal with Bosch in NZ for warranty now, Being mail order from Pole I don't suppose you have much luck with them for warranty?
Plummet
Flash Git
Yep, Its currently at the bike shop and they are dealing direct with bosch nz.
PS that is how it would role if pole was still in business and with any other brand. The bike shop deals directly with bosch.
With that said i'm likely to be charges labour for work done by the bike shop. I'm ok with that, they need to make money and I enjoyed the cost savings of importing a bicycle far cheaper than what I could purchase a similar thing here in NZ.
JP-NZ
E*POWAH Elite
Nice, a guy I know works at Marleen here in Christchurch that deal with most Bosch stuff in NZ. Hope its nice quick swap for ya.
This was a motor that just kept giving!! After overhauling your motor Bones, we popped it into our test bike and it still whined!Wow that looks a mess Peter!.
Seems like I wasted my time with the seal kit a few months back
Great pictures and diagnosis.
Do I need to sell the family jewellery?
Like you say it's never been pressure washed but it's been through plenty of water crossings.
It is an MTB that gets some stick and we are in the UK
This can only mean one thing, the top armature bearing had failed. This is extremely rare, but it's also the only, currently, unchangeable bearing in the whole motor. This goes on... we can't change the armature bearing because the magnet that tells the sensor on the PCB when to fire each phase of the three phase motor, is pressed on above this bearing. The magnet is extremely difficult to remove and replace in exactly the right position, and best left well alone! This means that we can't just swap the armature either, because this is calibrated to the PCB.So, you now have a quiet motor with a lower mileage, thanks to a donor motors PCB and armature.
For those of you with a "SMART" Bosch, this sort of repair will not be possible
This is something that the home mechanic has no chance of successfully repairing if specialist like yourselfs won't takle it!This was a motor that just kept giving!! After overhauling your motor Bones, we popped it into our test bike and it still whined!
So, you now have a quiet motor with a lower mileage, thanks to a donor motors PCB and armature.
For those of you with a "SMART" Bosch, this sort of repair will not be possible
As per my PM, again many thanks for all the work involved and not giving in on the nightmare job!
Your a Star Peter, but keep that to yourself
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