Anyone ever replaced a CX Gen 2 for the new Gen 4

[EdTy]

Quite happy with my current e-mtb but wouldn't mind upgrading the Bosch Gen 2 CX motor for a new Gen 4.
Has anyone ever tried this? Easy or difficult?

 

[Mteam]

Will a gen 4 fit in the place of a gen2? Isn't the gen 4 a lot smaller than the gen 2 and the mounting bolts in different places?

 

[Voluptua]

Smaller ought to be feasible, with some kind of adapter plate. It's bigger that would give you problems.

 

[Beekeeper]

I didn’t know Bosch sold motors to the general public

 

[cemoz]

I was hoping to do it, was studying product design and I still couldn’t get hold of the gen 4 motor by itself.Tried for over a year, Bosch their distributors or any LBS that stock them will not sell you one. It’s only available as a replacement (gen 4 for gen 4) the only way you will get one is through eBay and they don’t come up that often.

If I go back to working on the project I was trying to get it for I’ll probably buy the cheapest hard tail I can find with the gen 4 and take the motor out of that.

 

[EdTy]

I was hoping to do it, was studying product design and I still couldn’t get hold of the gen 4 motor by itself.Tried for over a year, Bosch their distributors or any LBS that stock them will not sell you one. It’s only available as a replacement (gen 4 for gen 4) the only way you will get one is through eBay and they don’t come up that often.

If I go back to working on the project I was trying to get it for I’ll probably buy the cheapest hard tail I can find with the gen 4 and take the motor out of that.

Thanks cemoz.
As mentioned above by other members its seems doable since its a smaller motor, and would probably need some kind of adapter to fill in the empty spaces.
Amazing that Bosch won't sell you the stand alone motor, some kind of deal with manufacturers to promote new bike sales??? or maybe they want to make sure their motors are installed correctly?
I'd be interested in learning if you ever manage the switch.

 

[EdTy]

Thanks cemoz.
As mentioned above by other members its seems doable since its a smaller motor, and would probably need some kind of adapter to fill in the empty spaces.
Amazing that Bosch won't sell you the stand alone motor, some kind of deal with manufacturers to promote new bike sales??? or maybe they want to make sure their motors are installed correctly?
I'd be interested in learning if you ever manage the switch.

BTW, just found this listing on ebay if your interested.

 

[Beekeeper]

I think @Bearing Man has managed to put a newer version of a motor into a bike by making a special mounting bracket.

 

[Bearing Man]

We have looked at this several times and the Gen 4 is not only smaller it is much narrower. It could be made to fit and would plug into existing battery and controls, but getting around crank centralisation and going from a small chainring to large, this has to line up and miss everything while keeping the motor central in a bigger hole without the crankarms hitting the frame or swingarm. To be honest there are absolutely no benefits and much grief.
Later this year when the madness dies down, we will be looking at an engine swap that would keep the older bikes going and would definitely be worth the effort. ?

 

[cemoz]

Thanks for the look up of the gen 4 EdTy, I hope to go back to it at some point. Just haven’t got the time to mess around with mounting plates and sorting out the crank chain line at the moment. I picked the frame up by itself from Germany last year it’s rear end was going to be modified as well. I got sick of it just sitting there so are building it up with the gen 2 so it’s at least rideable for now.

 

[Cobee]

Hi, I’m in progress.
I’am not sure that will be work perfect. I will check it , I like it
Bike Trek Powerfly 9,7 lt plus 2019 in carbon.
Mount plates made from stainless steel 1,403 cutted on laser and milling.
Later I will design Alu covers.

 

[2wheelsahead]

Hi, I’m in progress.
I’am not sure that will be work perfect. I will check it , I like it
Bike Trek Powerfly 9,7 lt plus 2019 in carbon.
Mount plates made from stainless steel 1,403 cutted on laser and milling.
Later I will design Alu covers.
View attachment 113207 View attachment 113208 View attachment 113209 View attachment 113210 View attachment 113211 View attachment 113212

Bravo…how does it ride?

 

[Cobee]

first feeling - quite ok. but I was try found which motor is stronger, more aggressive. I think that gen2 is very good motor comparing with gen4. I have a good comparison ( two motors on the same bike). and I’m still thinking to go with this far or back to old. Because is not big different with power.
Old motor have some disadvantages.
Noisy / sharp start stops / heavier /

 

[Bearing Man]

first feeling - quite ok. but I was try found which motor is stronger, more aggressive. I think that gen2 is very good motor comparing with gen4. I have a good comparison ( two motors on the same bike). and I’m still thinking to go with this far or back to old. Because is not big different with power.
Old motor have some disadvantages.
Noisy / sharp start stops / heavier /

I still think that if you can keep it dry, Bosch Gen 2 is one of the best motors built to date. It's built like a tractor gearbox inside and uses mostly tried and tested vehicle components in the electronics. The PCB is mounted at the top of the motor, so it's not sitting in the water if any gets in and for an extra kilogram you get a motor that would knock a tree over whilst towing your mate and carry on!

 

[Cobee]

I was sell gen4 today
Bearingman. My gen2 have a ca. 2000km. On crank I feel small loose maybe 1-2mm on crank end. Noises are quite standard. When should I implement repair kit ? I found Zestaw naprawczy Bosch silników 2 generacji
Ca.100$

You are right - motor is like tractor

 

[Bearing Man]

I was sell gen4 today
Bearingman. My gen2 have a ca. 2000km. On crank I feel small loose maybe 1-2mm on crank end. Noises are quite standard. When should I implement repair kit ? I found Zestaw naprawczy Bosch silników 2 generacji
Ca.100$

You are right - motor is like tractor

That is not a lot of mileage, so I would be very surprised if you need a service kit just yet, unless you spend a lot of time off road in mud and water. If the bearings were damaged or worn, you would hear a rough sounding noise! If you fit this service kit DO NOT fit the felt seals, they will destroy your motor, throw them in the bin!

 

[Cobee]

If someone need adapters Bosch Performance Line CX gen2 to gen4 Please Priv contact.

 

[Johan G]

Hi Cobee, I am new on the forum an unable to send private messages, but I need an Gen 4 motor to Gen 2 Frame. I hope you still have one left. Please contact me on [email protected]

 

[Jlarsson33]

If someone need adapters Bosch Performance Line CX gen2 to gen4 Please Priv contact.

I wrote to you, interested in the adapters

 

[Olle]

Hi Cobee i am interested in adapter from gen2 to gen4 if you want you can send to my email [email protected]

 

[Cobee]

It works on my trek Powerfly 9.7 gen2

 

[Cobee]

Little cutting left side cover.
New alu right cover will painted in black.

 

[Cobee]

Little cutting left side cover.
New alu right cover will painted in black.

View attachment 135415 View attachment 135416

 

[Angelosooso]

I'm quite impressed about the job you've done, that means there's no need to stay in the "old" motor and 2 options are available.

 

[Angelosooso]

BTW, I wonder if the adapters would fit any bike brand, I guess they will, as the engine mount is the same, anyone has tried the adapters on a Lapierre?

 

[Cobee]

Thanks. Here are adapters on my second bike trek Powerfly 9.9. Right, engine mount are the same.

 

[Cobee]

Please see movie with replacing motor in my ebike 🫣

 

[Cobee]

I have 8sets to sell. If someone want please write on priv.

 

[arildl]

I have 8sets to sell. If someone want please write on priv.

Hi Cobee!
I am stunned about your work - and would love to buy a set of adapters.
Unfortunately I got a link to your work by a friend, so I am new to this forum and can not send PM's yet.
I really hope you still have available adapters in stock for me.
Best regards,
Arild, Oslo - Norway

 

[Cobee]

Hi Cobee!
I am stunned about your work - and would love to buy a set of adapters.
Unfortunately I got a link to your work by a friend, so I am new to this forum and can not send PM's yet.
I really hope you still have available adapters in stock for me.
Best regards,
Arild, Oslo - Norway

Yes i have, please write to me [email protected]