Bull's 4th gen Bosch first ride very limited power uphill.

Dinnerfork

New Member
https://www.bullsbikesusa.com/copperhead-evo-am-3-750.html This is the bike that I've purchased after my Emotion Atom Lynx with a brose motor was stolen. I went out today and it has been some time since I've last ridden, but I felt a huge difference in power from my previous bike with a brose 250w setup. Is there a break in time where it will power up more later? Is this something I can adjust via an app. I was in "Red" mode on most of the steep hills in my area. On my previous bike the top mode felt like a luxury more than a necessity.
 
Strange! The 85 Nm motor should be very strong. Can you look up assistance settings, perhaps in the Flow App? (I am not a Bosch user, just curious).
At what cadence are you pedalling uphill? Fast? Slow?
 
I Downloaded a Bosch app on my phone but in not sure it is the right one. I don't think there was flow in the name. I was downshifting quite a bit so the cadence felt fast for me. I'll try downloading the flow app and getting some settings info.
 
Downloaded the App. In turbo mode Assistance is set to default and is at 0 in the middle. max torque 85nm maxed max speed 19mph. Dynamic is set to 0 default middle as well. All other modes were set to the same.
 
Downloaded the App. In turbo mode Assistance is set to default and is at 0 in the middle. max torque 85nm maxed max speed 19mph. Dynamic is set to 0 default middle as well. All other modes were set to the same.
What country are you from?
As I understand, your e-bike is the Smart System one. I hope Smart System users would chime in.
 
Your e-bike is Class 1 (20 mph) and the Bosch motors are known of reducing the assistance or cutting off before 20 mph. Your dealer might change the wheel circumference to facilitate assisting to 20 mph. On any climb, downshift and pedal at least 70 rpm. These motors love to be spinned and give you a lot of boost if you do that!
 
Your dealer might change the wheel circumference to facilitate assisting to 20 mph
No dealer can do that. You should know by now.
But no worries, looks like most users don't know what the wheel circumferece correction is for and how it works.

Edit:
(I am not a Bosch user, just curious)
Ok, now I understand 😂

On any climb, downshift and pedal at least 70 rpm
That is most likely impossible at 4Mph.
@Dinnerfork just ride in the first gear when it is steep. I have no problem riding 30% on dirt roads even with camping gear.
 
when you are lower then 80 rpm and putting out 450 watts you dont see much difference in the modes. you have bottomed out the torque. you have to get to 80 rpms to get more.
 
Just got my Canyon with Bosch Performance Line CX. Download the app on my phone, everything set at default. This is my first ever e-bike so I can‘t compare it to anything else. But I am amazed at how well it climbs on steep hills, on setting just above the eco mode. But of course, I’m still doing most of the work, and spinning at high cadence.
 
Just got my Canyon with Bosch Performance Line CX. Download the app on my phone, everything set at default. This is my first ever e-bike so I can‘t compare it to anything else. But I am amazed at how well it climbs on steep hills, on setting just above the eco mode. But of course, I’m still doing most of the work, and spinning at high cadence.
That is what I would expect from a CX e-bike. The CX is a climber!
We still don't know what grade hill @Dinnerfork tried to climb, and at what cadence. A mid-drive motor has to spin to deliver the power!
 
I though manipulating the wheel circumference within 5% was doable?
Correct, but that only adjusts the displayed speed to correct it when using different size tires. It can be done by anyone using the settings menu on the bike computer. It does not affect the real speed limit. You don't go 5% faster if you lower it 5%, it only displays 5% faster speed. But you are not alone, about 99% don't understand it.

A mid-drive motor has to spin to deliver the power!
Correct. No power if you don't pedal 😂
But the Bosch CX already has good torque at a cadence of 60rpm.
 
You don't go 5% faster if you lower it 5%, it only displays 5% faster speed. But you are not alone, about 99% don't understand it.
I beg to differ. If you modify the wheel circumference, the speed sensor readouts are interpreted by the control system to adjust for a new tyre size. The control system thinks you are riding slower, so it will start cutting off a little bit later. Therefore, getting at 20 mph should be possible.

The control system does not get any other e-bike speed information than the rear wheel rpm. The calculated speed is the product of rpm and the WhC. Please prove a Bosch E-bike can calculate the e-bike speed otherwise.
 
I beg to differ. If you modify the wheel circumference, the speed sensor readouts are interpreted by the control system to adjust for a new tyre size. The control system thinks you are riding slower, so it will start cutting off a little bit later. Therefore, getting at 20 mph should be possible.

The control system does not get any other e-bike speed information than the rear wheel rpm. The calculated speed is the product of rpm and the WhC. Please prove a Bosch E-bike can calculate the e-bike speed otherwise.
See, you don't get it. Don't worry, you're not alone.
The Bosch system has two circumference settings. The fixed one that is set by the manufacturer and a second one for the adjustment the customer can do for the tire size tweaking to get the displayed speed corrected. The first one is for calculatiing the cut off. It always cuts off at the same rpm of the wheel, no matter how you adjust the second one. Let's say it cuts off at 20mph when both are the same, let's say 2000mm.
If you set the second to +5% which is 2100mm, it will cut off at 21mph ON THE DISPLAY. Which is still 20mph because the system will always go by the fixed value.
However, if your tires are 2000mm and you change the tires to 2100mm tires, it will cut off at 21mph. No matter what value you set the adjusted circumference.

That's my final comment for that one as it says it all. If you still don't understand, I can't help.
 
The Bosch system has two circumference settings.
Only Bosch could be such paranoiac to invent this.
So you say an OEM such as Trek needs to order two different batches of CX motors: One batch for a road e-bike and another for an e-MTB? Think of a region such as EU where all e-bikes are 25 km/h.
That's my final comment for that one as it says it all. If you still don't understand, I can't help.
Oh, now I do understand.

Called bulls today and got it sorted out. I had to take my wheel off and readjust the wheel speed sensor. After about an hour of tinkering I managed to get it right. The difference is night and day and it feels like it will pull wheelies in low gear pretty easily. Their customer service was pretty decent.
Good to hear your issue was resolved! Many happy rides!
 
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So you say an OEM such as Trek needs to order two different batches of CX motors: One batch for a road e-bike and another for an e-MTB?
Not really unless you're talking about class 1 and class 3 (Pedelec or S-Pedelec). The software containers matter and values like wheel circumference can be configured by the manufacturer. You can have different bike IDs with the same hardware. The software container and bike ID must match the hardware.

Only Bosch could be such paranoiac to invent this.
It's the law in Europe that dictates it. Has to be street legal. Not like here in the US where there are no laws.
 
Called bulls today and got it sorted out. I had to take my wheel off and readjust the wheel speed sensor. After about an hour of tinkering I managed to get it right. The difference is night and day and it feels like it will pull wheelies in low gear pretty easily. Their customer service was pretty decent.
That was an easy fix. But should have displayed an error or wrong speed.
Even the 63Nm in the Gen2 speed can do 20% incline pulling my 80kg trailer on the test ride today. Will be even better when I get the Rohloff eShift soon.
20231013_181243.jpg

That's gonna be a nice Fahrradwohnwagen (bicycle RV trailer) when finished.
 
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