Is there an on/ off setting in the app that I missed?
I tried the kick back method and could not get it to work. But it's a useful feature to be able to control without having to hardwire a derailleur.
120 Nm update for the Bosch CX and CX Race Announced
- Thread starter knut7
- Start date
Is there an on/ off setting in the app that I missed?
I tried the kick back method and could not get it to work. But it's a useful feature to be able to control without having to hardwire a derailleur.
So it picks up any hub slack? I can see this being super useful for climbing, but hasn’t the new trend been to eliminate pedal kickback? Seems this would increase kickback. Would be cool to have one of the accessory buttons be able to activate/deactivate it for climb and descents.
It's not "activated," and there's nothing to get to the bottom of. The pre-tensioning is happening all the time when you're riding. The motor gives a little torque to take up slack in the drivetrain. Pedaling backwards is just changing the conditions, and the torque on the motor runs everything forward to eliminate slack. Nor is pedaling backwards while shifting some kind of hidden feature. There is no reason to even do that. You can understand the frustration of the manufacturers when users do goofy things with their products that make no sense, and then go around spreading misinformation on the interwebs.
Not only for the hub but also for the two freewheel clutches inside the motor. And if you don't pedal backwards it won't activate which should take care of pedal kickback.
The idea from Bosch is, that after some decent standing on your pedals and then moving into a steep/technical climb you can now get rid of any slack in the drive train or when accelerating out of a corner. The function is clearly targeted towards racing and therefore only available in Race, eMTB and eMTB+ modes.
How is pedaling backwards any better than pedaling forward to take the slack up though? Or how long would it tension I guess? If you are descending and coming up on a climb it seems easier to just pedal forward than getting a backward pedal in. You sure it’s not just always tensioning when on?
Bosch does not agree with you:
Why has the chainring been turning forward when I pedal backward since the latest update?
This is the visible result of the Drivetrain Tensioner. This offers added value, especially to performance eBike riders who expect direct, instantaneous traction. The Drivetrain Tensioner ensures direct response behavior, especially with a dynamic riding style, frequent load changes, and on technical terrain.In eMTB, eMTB+, and Race riding modes, the chainring moves slightly forward when you pedal backward. This process pretensions the drivetrain and closes the freewheel. The benefit for you: As soon as you start pedaling again, you'll have immediate traction.
This behavior might feel a little strange to you at first.
Source: Help Center - Bosch eBike Systems | Help Center
It is not.
There is a video from mister uphill flow Stefan Schlie who helped develop this. He demonstrated the feature and said, that after a decent most riders automatically do a short backwards pedalling before pedalling forward. He showed less than a quarter turn to activate the chainring.
But where are you seeing you have to backpedal? I can’t find that and it seems Bosch would put that out on how to activate it. I’m thinking you guys backpedaling is just making it try to pick up more slack and you’re seeing it tensioning, but it was already tensioned before you backpedaled.
Oh duh. Interesting. Pedaling forward seems like it’d do the same, but I guess I’ll be interested to see how you guys like it.
I was thinking it was just always tensioned when on which could be cool if you could click a button to deactivate it. Then you could run kickback hubs for free feeling dh then activate it coming up to uphill techy sections. Having to think about backpedaling seems odd to make this work.
the idea is that most people do it unconsciously when moving from the 3/9 o’clock pedal position used while descending to move to a oedal position
So this makes sense. I was riding with a good friend that was on an SL e-bike and as such I kept my Bosch in Tour+ mode for yesterday's ride. Sounds like the DT feature isn't available in the mode I was using most of the time.
I figured it was either the mode I was using, or possibly Bosch only activates it above a certain speed, now I have my answer.
I cheated a handful of times using my 4 week old knee surgery as my built in excuse, and I guess that's when I saw it working.
It wasn't just 'taking up a little slack', that front chain ring spun around 2 full rotations with my own eyes.
Why do you pedal backwards before you pedal forwards? Don't worry, after a little more practice you'll be able to overcome this newbie habit and ride some of the big boy trails.
or a reading problem… look a little up the thread…
Backward Pedalers of the World, Unite!
AlsbachRyder
New Member
- Feb 18, 2026
- 38
- 106
The drivetrain tensioner works even without explicitly pedaling backward—even in normal coasting mode without any intentional pedal movement, the chain is automatically tensioned on a straight stretch, or at the latest before an incline. Performs fantastic — instant power transfer when pedaling up to obstacles, no more kickback from the hub, not even when coasting before. I’m pretty impressed. 
(Tested on my Mondraker Crafty with XT Di2 8260 in manual shifting mode and with an electronic power supply to the Bosch Gen5 motor)
(Tested on my Mondraker Crafty with XT Di2 8260 in manual shifting mode and with an electronic power supply to the Bosch Gen5 motor)
But is Bosch saying you have to pedal backwards? Yes I know it says pedaling backwards you will see the chainring move, but is that just because it is taking up the sensed chain slack from backward pedaling? I feel like they’re saying it’s always tensioning the chain. Hence the reviewers saying while descending you notice less chain slap. They aren’t backpedaling the whole descent lol.
Edit posted same time as above comment, but yes I agree I don’t thing you have to backpedal to activate it lol. That seems ridiculous.
Edit posted same time as above comment, but yes I agree I don’t thing you have to backpedal to activate it lol. That seems ridiculous.
No, you don’t have to back pedal to activate it, the back pedal that moves the chain ring forwards a revolution or two that has been described appears to be a ‘happy accident’.
Exactly dude. Why are people saying that in here? That makes no sense to me. I get Bosch said you’ll notice that when you backpedal, but they aren’t saying that’s how to activate it lmao.No, you don’t have to back pedal to activate it, the back pedal that moves the chain ring forwards a revolution or two that has been described appears to be a ‘happy accident’.
It's the way of every forum. There are some who do things and who know things, and then there are those who spend their time browsing the internet for all the half-baked opinions that support their harebrained notions. Who knows, maybe this new fad will catch on. This time next year, the "influencers" will be furiously pedaling backwards as they test ride their factory loaners along the bridle trails. How long do you think it will take Avinox to catch up and develop a "Backpedal Mode?"
Plummet
Flash Git
towards the end of the year if I remember correctly
Dudley Do-Right , of the RMCP, has the solution sitting backward on a mountain bike (facing the rear wheel) and pedals backward relative to his body, he is actually pedaling forward relative to the bike's drivetrain.
There is a term in the snowmobile riders terminology, " riding Canadian" in the kindest sense of the term.
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Heated
Member
I believe It uses sensors that keep it disabled while Descending.
I have the dtswiss DF and i don't notice any difference from pre update When descending.
Joecrow
Active member
Nice to find that the update, or at least the "Extended Boost" has also been applied to Gen 4 Bosch motors.
Nice to find that the update, or at least the "Extended Boost" has also been applied to Gen 4 Bosch motors.
It’s in the SX motor as well, updated my Marin yesterday and saw it had been added.
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