Didn't see any new motors on the Bosch stand, but then again I was busy talking and may have missed something?
"2nd dead bosch gen 4 motor not happy
- Thread starter Geeman
- Start date
Not sure if it’s at their booth but the EMBN guy has been showing a few bikes with it. He was hinting around about it coming on some new bikes and would be out soon.
I know there seems to be a view from some that it's only emtbs that have motor/electric problems, but it's not always plain sailing... with other implementations.
www.pbo.co.uk
Theres also an interesting part about pursuing warranty claims against European manufacturers post Brexit
"Why changing to an electric motor was a disaster" - Practical Boat Owner
Felix Marks attempts to embrace a green future for his Tofinou 7, but his experiment with an electric motor proves costly when damp conditions prevail
www.pbo.co.uk
Theres also an interesting part about pursuing warranty claims against European manufacturers post Brexit
Just to provide a different perspective......
If motor manufacturers were to readily supply replacement parts would that add to the base cost for a motor? They do not after all sell anything direct to consumer so brands and/or lbs would have to carry stock.
There are many among us that think nothing of paying serious money for a new shock or fork, or supposedly more powerfull brakes, replacement wheels etc. Yet spending a similar sum for a new motor is considered a rip off?
Comparisons with motor vehicles do not hold water ( pun intended). A full BMW service is over £400...and that assumes there are no faults to deal with.
OK I expect a bike motor to at least survive the 2 year warranty period and some .....and we all know its biggest enemy is water whether out on the trail or when being cleaned so there are precautions we can take.
Knowing the cost implications post warranty I wonder if setting up a "diy" type insurance policy would settle buying nerves. ....e.g. put £20 a month into a dedicated motor replacement savings account.
If motor manufacturers were to readily supply replacement parts would that add to the base cost for a motor? They do not after all sell anything direct to consumer so brands and/or lbs would have to carry stock.
There are many among us that think nothing of paying serious money for a new shock or fork, or supposedly more powerfull brakes, replacement wheels etc. Yet spending a similar sum for a new motor is considered a rip off?
Comparisons with motor vehicles do not hold water ( pun intended). A full BMW service is over £400...and that assumes there are no faults to deal with.
OK I expect a bike motor to at least survive the 2 year warranty period and some .....and we all know its biggest enemy is water whether out on the trail or when being cleaned so there are precautions we can take.
Knowing the cost implications post warranty I wonder if setting up a "diy" type insurance policy would settle buying nerves. ....e.g. put £20 a month into a dedicated motor replacement savings account.
I think you are missing the point. When you buy a BMW you know you are in for high dealer servicing costs. When we bought our 'Bosch' bikes we didn't know the motors were irreparable if a sensor or PCB failed out of warranty. Many of us do not spend vast sums on the latest shiny bits either. They are sold as EMTB motors but you can't get them wet - that's the point - NOT FIT FOR PURPOSE.
Don't submerge them and don't aim a jet wash or hose at them....apart from that you should be OK. I have done thousands of miles on emtbs ...both Brose and Bosch since 2019 including 5 very wet uk winters....no motors problems.
Do you have a choice when riding a trail which becomes deeply rutted. You don't know the depth of the water and most of us cannot carry their ebikes to keep them dry!
I'm of the same opinion, I find that it’s the upside down world !
.. have a mountain bike and not be able to ride on paths with puddles or muddy areas..
Fortunately with my enduro or trial motorbikes it's not the same thing..
.. have a mountain bike and not be able to ride on paths with puddles or muddy areas..
Fortunately with my enduro or trial motorbikes it's not the same thing..
Yes, my 250 enduro has no issues with the motor being submerged during river crossings, ruts etc.I'm of the same opinion, I find that it’s the upside down world !
.. have a mountain bike and not be able to ride on paths with puddles or muddy areas..
Fortunately with my enduro or trial motorbikes it's not the same thing..
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If they adopted IP67 waterproofing standard at the design stage, the motor could be submerged for 5 minutes up to 3metres depth without ingress. Many electric motors are IP67, why not these?
I'm not suggesting submerging to 3m as the battery wouldn't like it.
I'm not suggesting submerging to 3m as the battery wouldn't like it.
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This is from a post I wrote a little while ago. It may help with some more understanding.
As a vehicle mechanic and then a motorcycle mechanic with my own repair shop, and a keen off-road motorcycle rider. And now the owner of the worlds first and largest ebike motor repair business. I am extremely familiar with all the practices used in all these fields of engineering. As others will know from many of my previous posts, I am not always on the side of the manufacturer. However, I can see the issues they face.
Firstly, There are also some very big differences between an ebike motor and that of a combustion engine. The two main differences are oil and friction. A motorcycle engine has external seals and behind these are usually open bearings that are lubricated by the engine oil. This means, if you manage to get a little water past the seals, it goes into the oil, where it is condensed out on your next ride. (Water will penetrate a seal when a pressure washer is used and that's why you have to replace swing arm, wheel and headstock bearings etc.). Seals also create friction. Again, no great problem for a combustion engine, it has power to spare. One other thing is that the oil is under pressure and the engines have breathers, this stops water being drawn into the motor when it enters water.
An ebike motor has none of these things, so if water enters a bearing, there is no oil to wash it out, it's in their oxidising the bearing races until the bearing fails, this is the same with grit or dirt, there is no oil filter. If seals strong enough to withstand water pressure of any kind are added, your power will go down and your battery consumption will go up. Your motor normally has 250W of power as apposed to 30+BHP of an engine.
When you couple this with the fact that 90% of all ebikes made are road bikes, that suffer none of these issues, you start to see a bigger picture. Now I am still not saying that the ebike motor manufacturers are right. I believe each manufacturer should produce a dedicated more powerful and totally sealed unit, but currently it will come with a detrimental cost to your battery range. This would ultimately be acceptable to some but totally unacceptable to others. I'm guessing those living in dry countries would be properly upset!
There will be solutions one day, but they will always be compromises unless battery technology changes and we can then have it all.
As a vehicle mechanic and then a motorcycle mechanic with my own repair shop, and a keen off-road motorcycle rider. And now the owner of the worlds first and largest ebike motor repair business. I am extremely familiar with all the practices used in all these fields of engineering. As others will know from many of my previous posts, I am not always on the side of the manufacturer. However, I can see the issues they face.
Firstly, There are also some very big differences between an ebike motor and that of a combustion engine. The two main differences are oil and friction. A motorcycle engine has external seals and behind these are usually open bearings that are lubricated by the engine oil. This means, if you manage to get a little water past the seals, it goes into the oil, where it is condensed out on your next ride. (Water will penetrate a seal when a pressure washer is used and that's why you have to replace swing arm, wheel and headstock bearings etc.). Seals also create friction. Again, no great problem for a combustion engine, it has power to spare. One other thing is that the oil is under pressure and the engines have breathers, this stops water being drawn into the motor when it enters water.
An ebike motor has none of these things, so if water enters a bearing, there is no oil to wash it out, it's in their oxidising the bearing races until the bearing fails, this is the same with grit or dirt, there is no oil filter. If seals strong enough to withstand water pressure of any kind are added, your power will go down and your battery consumption will go up. Your motor normally has 250W of power as apposed to 30+BHP of an engine.
When you couple this with the fact that 90% of all ebikes made are road bikes, that suffer none of these issues, you start to see a bigger picture. Now I am still not saying that the ebike motor manufacturers are right. I believe each manufacturer should produce a dedicated more powerful and totally sealed unit, but currently it will come with a detrimental cost to your battery range. This would ultimately be acceptable to some but totally unacceptable to others. I'm guessing those living in dry countries would be properly upset!
There will be solutions one day, but they will always be compromises unless battery technology changes and we can then have it all.
I wonder if it's a "friction" thing. Our dirt motorcycles and 110V AC electric motors have the ability to live with the drag of very effective, quality seals. Maybe ebike manufacturers are correct or at least believe that heavy duty sealing of ebike motors will result in a negative issue the motor will have to overcome. Just speculating...no engineer here whatsoever.
Edit to add: Ooops, I notice that while I was typing my post bearing man mentioned one possibility of seal drag. So maybe I am an engineer...LOL!...no...just kidding.
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Might be why ZF have gone oil filled?
How about 2 specs of motors, one sealed to IP67 with slightly less range but able to be submerged and the other the same as now?
That will be the same scenario as the Bosch Gen 3 and 4. One will be cheaper because of less seals and machining, so that will be put in the lower end emtb's and it would all start over again!
But I totally agree, that each manufacturer should make a dedicated emtb motor. And any bike manufacturer found fitting a road bike motor in their gravel or mountain bike, should not get warranty.
Well once your ebike motor is obsolete, and it subsequently fails, how will you feel then? Another thing with ebikes is, replacing a frame isn’t easy or cost effective, so basically once the next model of ebike motor is out the clock is ticking on your bike.
New wheels? Well if I break a spoke, or the wheels bearings go – I fix these things, no I don’t buy a new wheel unless I really have to. My shocked failed. Happily, Fox, unlike Bosch, support their products and I sent it off to the service centre and it came back like new.
I note what bearing man says. But here’s a few other thoughts.
My experience of bicycle shops is (as a new customer walking in the door), ask them how reliable their ebike motors are and they will tell you they are bomb proof. They’ll emphasize the 2 year warranty etc.
In the UK on an emtb the Bosch motor seems to last between a couple of 100 miles to a few thousand miles. That is crap.
I’ve never pointed a pressure washer at mine, but I have repeatedly carefully hosed it down. I don’t use the hose at all now. So we’ll see how long my rebuilt refurb lasts.
There is no support. Bosch, for example don’t provide spares. Like I say, once Bosch come out with a new motor unit, the clock is ticking on your ebike as a whole. If the motor goes, you may as well bin your bike.
The other issue is service. Should these seals be service items ie a recommendation that the seals are renewed every 12mnths. Ie should this be an official service item.
What sort of market do the system manufactures, bicycle manufactures and retailers want? The bicycle market is already shrinking. Things like big bills for replacing a cable or a hydraulic line because the bicycle company thought it would be cool to route them down the headset and right through the frame. Ebike motors that aren’t supported by the manufacturer, and whole ebikes that quickly become basket cases when the unsupported drive unit is updated by the manufacturer.
None of this stuff is gonna do that much good for the ebike market or the bicycle market as a whole.
My experience of bicycle shops is (as a new customer walking in the door), ask them how reliable their ebike motors are and they will tell you they are bomb proof. They’ll emphasize the 2 year warranty etc.
In the UK on an emtb the Bosch motor seems to last between a couple of 100 miles to a few thousand miles. That is crap.
I’ve never pointed a pressure washer at mine, but I have repeatedly carefully hosed it down. I don’t use the hose at all now. So we’ll see how long my rebuilt refurb lasts.
There is no support. Bosch, for example don’t provide spares. Like I say, once Bosch come out with a new motor unit, the clock is ticking on your ebike as a whole. If the motor goes, you may as well bin your bike.
The other issue is service. Should these seals be service items ie a recommendation that the seals are renewed every 12mnths. Ie should this be an official service item.
What sort of market do the system manufactures, bicycle manufactures and retailers want? The bicycle market is already shrinking. Things like big bills for replacing a cable or a hydraulic line because the bicycle company thought it would be cool to route them down the headset and right through the frame. Ebike motors that aren’t supported by the manufacturer, and whole ebikes that quickly become basket cases when the unsupported drive unit is updated by the manufacturer.
None of this stuff is gonna do that much good for the ebike market or the bicycle market as a whole.
Interestingly I ride a BMW R1250R. It doesn’t cost anything like as much to maintain as my ebike, nor does my car for that matter.
Another fun wee point. There is an ‘issue’ with the shaft drive on most of the water cooled series of BMW boxer engines. It includes my R1250R. BMW have just updated their service schedule for these bikes. They recommend inspecting the shaft drive every 12,000 miles – this will be charged to the customer.
Regardless of whether or not the customer agrees to the inspection, BMW will replace the shaft drive unit every 36,000 miles for the life of the bike.
Oh just booked my BMW in for its annual service – 190 quid.
Bosch don't seem to care about their customers.
Where do you get 10% from? They might do it if they can corner the market.
I take your mechanical experience onboard but with a fair bit of history myself I feel a 'decent enough' sealing system would come with only a marginal reduction in range. Theres so many ways to seal a shaft and granted they normally like to be splash fed oil but theres some decent self-lubing seals out there nowadays and the additional friction would be moot imo. Either way, I'd take the power/mileage reduction any day in order to not fret about getting my motor wet, nor the £££'s it costs to replace/rebuild it.
Even a simple fork seal doesn't add a huge amount of friction and we (well I don't) worry about water entering forks in the rain and the lowers filling up and thats even dealing with a lot more grief than a shaft which is simply spinning horizontally. If it makes people happier we can all spin a fork seal on a stanchion and feel for ourselves how much friction it takes. If thats still too much friction for some when theres 800 odd watts helping you out then I think they may have other issues and should turn to roadie levels of friction OCD.
I generally have a lot of time for Bosch engineers and I'm staggered that we have this weakness tbh. If it is in order to eek out maximum numbers for their sales reps to willy-wave down the pub then I feel they have dropped a ball.
I'll throw out something from left field here. I wonder if companies like Bafang would consider making replacement motors for bikes that were designed for Bosch motors or others? Stay with me for a second.
Coming from a performance car and motorcycle background, it's nothing at all to stuff a GM LS motor into all kinds of vehicles with simple motor mount kits readily available. I know, I know, a different application perhaps, but in my mind's eye I can see Bafang making some motors that would exchange into the frames designed for Bosch motors which are somewhat plentiful I would think. The casting for such wouldn't require reinventing the wheel.
I come from a background of running a 2003 Santa Cruz Bullit with a Bafang BBSHD motor that worked great for three years...and is still working but replaced by a Gen 2 Trek Rail 7. Pedal cadence/torque sensing aside, I'd wouldn't lose a second's sleep running that BBSHD in my Trek if it was frame mounted like an OEM emtb.
Hey...just thinking out loud here where the idea of not having to throw away frames because of continued motor failure or performance issues. And honestly I'm quite happy with my Bosch motor in my Trek...but I'm in the dry riding conditions of Texas.
Coming from a performance car and motorcycle background, it's nothing at all to stuff a GM LS motor into all kinds of vehicles with simple motor mount kits readily available. I know, I know, a different application perhaps, but in my mind's eye I can see Bafang making some motors that would exchange into the frames designed for Bosch motors which are somewhat plentiful I would think. The casting for such wouldn't require reinventing the wheel.
I come from a background of running a 2003 Santa Cruz Bullit with a Bafang BBSHD motor that worked great for three years...and is still working but replaced by a Gen 2 Trek Rail 7. Pedal cadence/torque sensing aside, I'd wouldn't lose a second's sleep running that BBSHD in my Trek if it was frame mounted like an OEM emtb.
Hey...just thinking out loud here where the idea of not having to throw away frames because of continued motor failure or performance issues. And honestly I'm quite happy with my Bosch motor in my Trek...but I'm in the dry riding conditions of Texas.
Hattori-Hanzo
Active member
Converting a frame to fit a different motor is the easier part, there's a thread showing a Shimano motor being replaced with a Befang.
The harder part is getting the electronics and battery to work with the motor, it would likely require the electronics and battery to also be replaced, this can be difficult and costly.
The harder part is getting the electronics and battery to work with the motor, it would likely require the electronics and battery to also be replaced, this can be difficult and costly.
I fully get what you're saying Planemo, and I agree with much of it. As said before, I am not standing up for the manufacturers, they are capable of doing that themselves should they want to, but I did used to work for a very large corporate company as a technical engineering manager, so I can understand some of the other issues faced.
Unfortunately, it's not just a friction issue. There are many design change issues, tooling issues, testing issues etc.
People used to say to us... why don't you just change that bit!? This would require 3 months in a design department, a £50,000 tool to make 10 test or prototype parts at a ridiculous cost per piece. Then these parts would have to go through a 10,000 hour test run (which may fail or go wrong and have to be re-started!), then a salt spray test, emf, test etc. etc.
This used to take around 5 years in total. This would equate to Bosch's current progress of releasing a new motor every 4 to 5 years.
If we look into the technicalities of sealing a spinning splined shaft within another spinning splined shaft against very high pressure water. this to be done without the motor sensing drag and thinking you're still pedalling, or the torque sensor thinking you're putting more effort in than you are etc. I could write a book on the issues we've had trying to seal these motors.
Then the more waterproof the motors are made, the deeper water everyone will ride through, so then the electronics, plugs, gaskets and batteries would all need redesigning!
As I said, it is coming, manufacturers have made some mistakes, but things are definitely changing, they are listening, it will be fixed and these issues will go away. It just takes time.
Yes, I know we should not be the Guinea pigs, and the design should have been right in the first place. This is also a subject I have written extensively about, but sadly do not have time to repeat this today.
Standardisation in this sphere is sorely missing but it's not much different to other worlds. A VW Golf waterpump won't fit a Vauxhall Corsa etc. although I remember happily the says when I ran a Cayman & bought plenty of spare parts from Skoda, after working out VW use common engine bits across the group & I could duck the prestige tax on oily bits.
As Ebikes are an arms race & subject to galloping technical innovation and still a relatively minority enterprise, I can't see that changing either, another aspect where the incentive just isn't present.
I'm different to some i think, i bought mine accepting that the motor is likely scrap either during or after the warranty and will need replacing before the bike does. It potentially means a cost of £500-1000 but lets be fair here, that's not a completely insane amount after 2 years of ownership, if it was a car and needed a new clutch at £500 you'd be OK with that, or an air-con condenser you'd accept that too. So I don't see why people think a motor should last forever.
Just accept it's broken, replace it, get a new 2 year warranty and start again
Those who expect stability in the midst of the current eBike motor "arms race" for market share had better wise up to the fact that it ain't gonna happen. Stability is the enemy of innovation.
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