Evelhornet
Member
What kind of sorcery is this! š«£
I'd like to see what it looks like inside next (after a few more weeks of dip testing) Not that I'm sceptical or anything
"2nd dead bosch gen 4 motor not happy
- Thread starter Geeman
- Start date
I'd like to see what it looks like inside next (after a few more weeks of dip testing) Not that I'm sceptical or anything
the answer to my question to Bosch or my bike is also for home/work traffic...because in the Netherlands it still rains every day
Rutger, We're sorry to hear about your problems. However, this problem does not occur often and Bosch does use a rubber ring on the bearing to seal the shaft. Our components are splash-proof and therefore not intended for driving in heavy rain. We recommend that you have your ebike regularly serviced and checked for possible missing seals. then these problems will no longer occur as long as the eBike is used responsibly, of course. We will have to refer you to your nearest Bosch dealer. This can help you with this.. Here you will find the link to your nearest Bosch dealer: EN: Een dealer zoeken - eBike-informatie, advies en proefritten zoeken BE: Een dealer zoeken ā eBike-informatie en proefritten zoeken We wish you a very nice day! If you have any further questions, we are always here to help. Kind regards, Daniel Vanackere Your Bosch eBike Team
I'm going to send Bosch mail number 3 now
Is that an official response from Bosch? Splash proof, and not intended for use in the rain?
FFS!
@Bearing Man Is it possible to oil fill EMTB motors at service? Would it work?
It would definitely help! But not possible on motors that are not currently designed for it.
This is a great video, but missed the real reason motors fail. Putting aside pressure washers etc.
As we all know, you can ride your emtb through deep water and nothing happens, it will appear to be fine! Unfortunately, the failure will often occur months later when you have completely forgotten about the dunking you gave it 6 months ago. It will be a complete mystery why this happened!
The reason for this; with a motor in good condition, water will usually just enter into the outer bearings and not the motor at first. (Sadly, no one checked for this in the video). The bearing is still quite well sealed at this point so the water can't get out again. This starts slowly corroding the bearing race and ball bearings, this wears the ball bearings down until the bearing seals can no longer fit properly, allowing water to flood into the motor itself and eventually kill it!
Best way to deal with bosch CX motor issues is to ride them however you like... And then when it breaks, send it to @Bearing Man to switch out the motor for a new one! Always worked well for me! I moved up north last year but when this current motor dies, I'll go all the way to Hampshire just to get Peter to change the motor without a second thought. Service second to none.
Quick question:
Does anyone here have a relatively loud motor whine when they get to the 15.5mph cut out?
Does anyone here have a relatively loud motor whine when they get to the 15.5mph cut out?
We are a day or two from receiving the final parts that we had manufactured to achieve this, will do a reveal here firstWhat does the Crankshaft and sprocket carrier upgrade involve, Pete? Just curious is all.
lar1337
New Member
Think the industry needs to take some cues from marine tech, jet skis, outboard motors etc.......just a thought
I donāt think thereās a silver-bullet that would prevent our motors from failing. The combination(s) of abuse's are endless. Most motor manufacturers have done almost everything they can think of to prevent motor failure. We are essentially the test-monkeys for future motor development on ebikes.
Iād like to stretch the longevity of my motor forever ā¦but thatās unlikely to happen. But there are a few things I can do to help (specifically regarding the Bosch CX Gen4 and probably most ebike motors).
I donāt power wash my bike.
I donāt use detergents or cleaners on my bike.
I try to maintain proper cadence.
I service or replenish the external oils or grease on bearings or seals on most moving parts.
I try to maintain stuff.
I rely on expertise e from Pete or some reviews from Jonesy (or whoever), and some of my own experiences.
And my environment differs from yours. (Heat, cold, debris, mud, water, dust, use or abuse ā¦etc. Thereās a list of things to consider.
I donāt think oil-filled motors are the absolute answer. Thereās a number of issues that can arise from that type of motor. Iāll still be searching for that silver bullet ā¦but in the meantime
, the market and manufacturing will evolve.
Iād like to stretch the longevity of my motor forever ā¦but thatās unlikely to happen. But there are a few things I can do to help (specifically regarding the Bosch CX Gen4 and probably most ebike motors).
I donāt power wash my bike.
I donāt use detergents or cleaners on my bike.
I try to maintain proper cadence.
I service or replenish the external oils or grease on bearings or seals on most moving parts.
I try to maintain stuff.
I rely on expertise e from Pete or some reviews from Jonesy (or whoever), and some of my own experiences.
And my environment differs from yours. (Heat, cold, debris, mud, water, dust, use or abuse ā¦etc. Thereās a list of things to consider.
I donāt think oil-filled motors are the absolute answer. Thereās a number of issues that can arise from that type of motor. Iāll still be searching for that silver bullet ā¦but in the meantime
, the market and manufacturing will evolve.I have wondered about fitting them above the bb area I.e. between the junction of the seat & downtube & linking a standard crank/bb set up somehow. This would look stupid, add weight, weaken the frame & raise the CoG & generally not work but would lift them away from the ground. I'm available (unsurprisingly) for consultation work.
ā¦and a third wheel ā¦you know ā¦just incase.
. Iām also available for consultation. 
"This starts slowly corroding the bearing race and ball bearings, this wears the ball bearings down until the bearing seals can no longer fit properly, allowing water to flood into the motor itself and eventually kill it!"
Would SS Bearings help or are they too soft to last?
@Bearing Man Yes, or Ceramic as I mentioned a while back on this thread.
Oh ok. In that case, do I get a refund? Because it's on my bill
Don't worry, you have all the good stuff in your motor 
With SS bearings it's more a case of finding them in the right size, with the right seals, at the right price! It's just not possible.
For the reasons @Spiff stated above, but also with ceramic bearings, there are very few sizes made and even fewer with seals. Ceramic bearings are not a fan of dirt and grit either.
Many manufacturers use their own bespoke bearing sizes and getting small quantities of ceramic bearings manufactured would not be economically possible.
I recently changed the front wheel bearings on my normy Lapierre Zesty, not seen it before but they were marked LLU. I looked them up & it denotes a bearing with a sealing lip on one side for higher sealing & intended for use where one side of the bearing is exposed to the environment. My takeaway from that is designers do what they can to prolong components but in the end, mechanical components invariably wear.
Any excuse to shoehorn a photo of this beast in.
Any excuse to shoehorn a photo of this beast in.
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Tick, Tick, Tick...The final countdown.We are a day or two from receiving the final parts that we had manufactured to achieve this, will do a reveal here first
I am eagerly waiting to see your fix.
The wait is over! A more comprehensive explanation, reasoning and price will be on our website as soon as I have time. I cannot confirm a price on here as prices change, but in the UK this should be just under Ā£200.00 Please note, the parts are not that expensive, but this motor is extremely time consuming.
Yours is just full of silicone sealant Rusty
Absolutely
We had a small batch of everything manufactured for testing. After testing we had a few left over and this is what we used to keep you one step ahead of everyone else Can I add mine for sale also, as it's got the indestructible parts fittedFor sale: Indestructible Focus Jam2 Ā£10,000
Besides all the other upgraded parts, it looks to me that the āsingle lip rotary sealā is one of the best solutions.
I now have 2 Bosch CX gen 4 motor sitting on my shelf and one in my bike, that will eventually fail. I feel like I can start becoming a submarine pilot again without the anxiety. (Within reason).
Iāll have to figure out the logistics of shipping a motor across the pond.
It's already been wet, just duct tape it to a polystyrene raft ...Besides all the other upgraded parts, it looks to me that the āsingle lip rotary sealā is one of the best solutions.
I now have 2 Bosch CX gen 4 motor sitting on my shelf and one in my bike, that will eventually fail. I feel like I can start becoming a submarine pilot again without the anxiety. (Within reason).
Iāll have to figure out the logistics of shipping a motor across the pond.
(Ps I think they have us/can agents)
Thatās salt-water! Did I mention that āthatās salt-waterā.
Ps; I need to find a good shipping agent.
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