Bosch CX Performance vs Performance Speed

volinbham

New Member
Wondering if there is really much real world difference in feel between the 2 Bosch 28mph motors.

I've read Bosch's and others' descriptions (CX more low speed torque, PS more power at higher speed; eMTB mode on CX) and know which style I'd prefer for my riding but I'm skeptical I'd notice the difference. Just wondering if it's an important or irrelevant consideration when choosing between models.

Anyone here with experience with both?
 

Nova Haibike

Well-Known Member
The CX is a 20 mph motor; only the Performance Speed is a 28 mph motor. The only way to get 28mph out of the CX is to use some kind of tuning product such as the BadAssBox or Bikespeed RS.
 
Wondering if there is really much real world difference in feel between the 2 Bosch 28mph motors.

I've read Bosch's and others' descriptions (CX more low speed torque, PS more power at higher speed; eMTB mode on CX) and know which style I'd prefer for my riding but I'm skeptical I'd notice the difference. Just wondering if it's an important or irrelevant consideration when choosing between models.

Anyone here with experience with both?
Hello,
I have a two Trek eBikes, an XM700 + Commuter with the Performance Line motor ( 28mph ) and a Powerfly 7 mtb with the Bosch CX motor. (20mph) . 'The only way to run the CX past 20mph is by installing a 'dongle' ..A speed restriction eliminator.
I installed a Speedbox2 on my Powerfly7 for a couple of mph above 20 and it works great...

https://www.derestricted-ebike.com/p/speedbox2-for-bosch-active-performance-cx

You asked....."Up to 20 mph, any real world difference in feel? " In my opinion absolutely. The Performance Line is no slouch, but the
additional torque across the CX motors entire range is a joy. The motor so smooth. Bosch makes good 'stuff'...not cheap, but good and dependable. 4000 miles combined on both bikes and not a single problem.

The torque on the CX motor is quite wide, not limited to low speed. I love the motor and how it performs on the Powerfly. In fact Iike the CX
motor so much, I'm seriously considering replacing the Performance Line motor on my XM700 with a CX motor, and the Performance Line motor is a great. Very powerful and silky smooth....The potential deal breaker is how much will the tariffs affect the cost of the motor.

"E-Wheels" wrote "The CX is noiser" With the style of riding I do, gravel trail ( rails to trails ) and paved roads I haven't noticed and discernible
noise difference between the Performance Line and the CX motors...Your milage may vary... : )

I hope this was helpful.
 

JayVee

Well-Known Member
Having ridden both systems quite a lot now, I think there are actually some fairly significant differences.

The CX is a tad louder but it also has a lot of low RPM grunt. If you're riding up a dirt trail and suddenly realise that you're in a gear that's too high but can't downshift, the CX might be able to pull you out of that situation whereas the Performance Speed will most likely stall if you're a heavier rider. The CX has noticeably more torque. To provide power on hills, the Performance Speed requires you to spin quite fast, meaning that you will need the adequate gearing. If you have steep hills (12% grade or more) and aren't particularly athletic, the Performance Speed is best paired with a 42T or bigger as the lowest gear. This is because as long as you can spin above a certain RPM threshold (let's say 80RPM), the Performance Speed provides power. The CX is much more tolerant. You could be close to 60RPM and it will still pull you up the hill. The Performance Speed suffers from Bosch's Achilles heel: it takes a lot of spinning to get the drive going, which is a somewhat arbitrary design choice. If your pedalling cadence is slow you might not like it. Despite all of this, I actually like the Performance Speed and it will probably power my next e-bike. I'm considering the 2019 Haibike Trekking Sduro S9.0 because (amongst other things) it's paired with an 11-46T cassette. After trying the Bosch with 11-42, I'm convinced that this is what's necessary to operate the drive correctly on hills and avoid stalls (which tend to happen with my 220 pound frame).
 

volinbham

New Member
Thanks - this is exactly what I wanted to know. I plan to ride much like John from Connecticut and I'm not a fast cadence guy. My riding is pretty leisurely and I'd like the grunt more than the top end.

One of the reasons I asked is I rode a bike with the Performance Speed and while it was fine it didn't seem to have the grunt that my rear hub Ocean Current does. I'm interested in a mid-drive so this information is very helpful. Thanks!
 

batmick1

Active Member
I test rode a bunch of different bikes and can confirm that the CX has the better low end "umph". And when you add a chip it becomes perfectly usable for higher speeds too. I put in the PearTune MSO and swapped the front sprocket to a 20t and now can easily cruise at 22-25mph and when I put the hammer down I can run 30mph for a while. I spin out around 35mph. I rarely ever use the Turbo mode, mostly Tour and occasionally Sport.
 

volinbham

New Member
Batmick1 - did you happen to ride any of the Brose or Yamaha options and if so could you comment on any differences?
 

batmick1

Active Member
Batmick1 - did you happen to ride any of the Brose or Yamaha options and if so could you comment on any differences?
There was no Brose bike available near me to test but I did try out a Giant Quick E and a different Haibike with Yamaha drives. Yamahe felt much more like a "regular" road bike and had significantly less pronounced pickup from zero than Bosch. I would have taken that too for my purpose but found a better deal on a bike in my size with the Bosch CX. The PearTune chip is available for Yamahe and Brose too, btw. so I never had to worry about picking a 20mph vs. a 28mph restricted model.
 

volinbham

New Member
There was no Brose bike available near me to test but I did try out a Giant Quick E and a different Haibike with Yamaha drives. Yamahe felt much more like a "regular" road bike and had significantly less pronounced pickup from zero than Bosch. I would have taken that too for my purpose but found a better deal on a bike in my size with the Bosch CX. The PearTune chip is available for Yamahe and Brose too, btw. so I never had to worry about picking a 20mph vs. a 28mph restricted model.
Sweet. Very valuable information - thanks for sharing.