Bosch CX gen 4 swap for gen 5?

[bikefisherguy]

The thing is, Bosch didn’t make your bike. Say Cube did. They certified it with Bosch being just one of many components. If they (or Bosch) actively help you modify the bike beyond its certified state, the bike is then potentially illegal. No company law dept is going to take on that risk.

It’s the same with cars - I can’t drop a 1000hp V12 into our Volvo, without it being certified by a specialist mechanical engineer who will give me a an IVA certificate saying it’s safe to be driven on public roads.

The difference being, ebike mfrs and motor brands are required to ensure the bike can’t break the law, and the liability lies with the mfr. A car IVA is about mechanical safety, because all cars are designed to be able to break the law all the time with no mfr liability.

Respectfully, you have no idea what you're talking about. Your logic is flawed. You are comparing apples to oranges

 

[Kiwimike]

Respectfully, you have no idea what you're talking about. Your logic is flawed. You are comparing apples to oranges

Thanks for the respect, but I’m 100% correct. E-bikes are certified as vehicles, as a system. Any major modification - like a different engine, driving wheel size etc, requires recertification, and that is why bike brands and Bosch don’t do it. Even a like-for-like motor swap has a lot of paperwork around it to be able to reinstall the replacement motor.

If I want to modify my car, I can and it just needs an engineer’s inspection. I agree, the two paths are very different - that’s what I was pointing out.

Lots of love, a Bosch-certified mechanic who does this stuff for a job.

 

[Cyclopathic]

The thing is, Bosch didn’t make your bike. Say Cube did. They certified it with Bosch being just one of many components. If they (or Bosch) actively help you modify the bike beyond its certified state, the bike is then potentially illegal. No company law dept is going to take on that risk.

It’s the same with cars - I can’t drop a 1000hp V12 into our Volvo, without it being certified by a specialist mechanical engineer who will give me a an IVA certificate saying it’s safe to be driven on public roads.

The difference being, ebike mfrs and motor brands are required to ensure the bike can’t break the law, and the liability lies with the mfr. A car IVA is about mechanical safety, because all cars are designed to be able to break the law all the time with no mfr liability.

Again, I hear you. But, they design in changes in bolt patterns etc again to ensure they renew life cycles and sell newer motors and help manufacturers sell new bikes.
I don't blame Bosch, this is the same with many of the Bike industries circling 'standards', which they change to sell new bikes, wrapped up in marketing that they give noticeable mechanical advantage.
Someone will sort the G4 to G5 conversion soon, I'm sure. I'd try, but I don't have the time (or patience lol)

 

[Cyclopathic]

Respectfully, you have no idea what you're talking about. Your logic is flawed. You are comparing apples to oranges

That's a bit harsh. To me, he makes logical sense, and what he says is true to the examples given, it's just not what you and I see as the key issues here.

 

[nickf]

For anyone who's still considering trying to swap their old gen 4 motor for a new gen 5, someone has done it here swap gen 5 motor

 

[Cyclopathic]

For anyone who's still considering trying to swap their old gen 4 motor for a new gen 5, someone has done it here swap gen 5 motor

Sadly not. He's confirmed G4->G5 isn't possible. His is G2->G5

 

[nickf]

Sadly not. He's confirmed G4->G5 isn't possible. His is G2->G5

You may be right, but he referred to gen 2 frames - not gen 2 motors. Also he was fitting his new motor into a 2019 Trek Powerfly rather then a Rail, so the motor orientation and mountings are not the same.

However, he does seem to mix his terms so it is a bit confusing. My 2022 gen 2 Rail has the gen 4 Bosch motor.

 

[Cyclopathic]

You may be right, but he referred to gen 2 frames - not gen 2 motors. Also he was fitting his new motor into a 2019 Trek Powerfly rather then a Rail, so the motor orientation and mountings are not the same.

However, he does seem to mix his terms so it is a bit confusing. My 2022 gen 2 Rail has the gen 4 Bosch motor.

Interesting! I hope you're right! I'll message him!

 

[Kiwimike]

Again, I hear you. But, they design in changes in bolt patterns etc again to ensure they renew life cycles and sell newer motors and help manufacturers sell new bikes.
I don't blame Bosch, this is the same with many of the Bike industries circling 'standards', which they change to sell new bikes, wrapped up in marketing that they give noticeable mechanical advantage.
Someone will sort the G4 to G5 conversion soon, I'm sure. I'd try, but I don't have the time (or patience lol)

The motor casings are different, different internals, materials, weight, features, design etc. The bolt pattern changed becuase it needed to to accommodate the improvements. Not everything is Big Ebike trying to stick it to customers.