Bosch Gen 5 efficiency?

nickf · Mar 11, 2025

emtbeast said:
Like already said, I would also point my finger to the Schwalbe radials. U already ride the Maxxis non-radials at extremely low pressures.

The Schwalbe radials are by some tests supposed to have cca 20% higer drag, have seen reports by other users on other online forums of extremely increased consuption on the radials.
In your case combine this, your extra low pressures, bit lower temperatures and a bit smaller battery, let's say all ads to cca 25% higher battery consumption overall

45km - 25% = 33,75km which is very near your number.

Also you can't realy equate access road km to uphill km, a better base value for emtb is altitude gain, distance should be second.

This guy on yt did quite some tests in Turbo mode on all the new batterys on the new Bosch Gen5 all on the same trail.

I asked about his trail, the area he does the tests has an average incline of cca 9 to 10%.

Altitude test in Turbo on the 600Wh

Distance test in Turbo on the 600Wh

These are all valid points, and you may well be correct that running the MM radials at low pressures does indeed add a significant amount of extra drag (although remember I run the Maxxis at very low pressures too). I can't comment on your 20% figure, but clearly if it could be as much as that then the tyres might be well be the main culprit for the low autonomy.

BTW I agree that you can't equate access road km with uphill off-road km, but in my case the Rail and the Vala did exactly the same steep, rocky off-road circuit, but the Rail then did - in addition - another 15km on the road. Even if this only equates to say 10km of trail riding it's still a noticeable difference and hence my enquiry into the autonomy of the Gen 5 motor/battery compared to the Gen 4. However, I would be quite happy to see that my single poor autonomy experience is just a statistical outlier - possibly explained by accumulated small factors - and that other Gen 5 riders get an equivalent performance+autonomy to the older Gen 4s. Hence this thread and everyone's useful comments so far

Sadly I don't understand German, so I can't follow the conclusions in the two YT videos. Can anyone summarise?

emtbeast · Mar 11, 2025

nickf said:
These are all valid points, and you may well be correct that running the MM radials at low pressures does indeed add a significant amount of extra drag (although remember I run the Maxxis at very low pressures too). I can't comment on your 20% figure, but clearly if it could be as much as that then the tyres might be well be the main culprit for the low autonomy.

BTW I agree that you can't equate access road km with uphill off-road km, but in my case the Rail and the Vala did exactly the same steep, rocky off-road circuit, but the Rail then did - in addition - another 15km on the road. Even if this only equates to say 10km of trail riding it's still a noticeable difference and hence my enquiry into the autonomy of the Gen 5 motor/battery compared to the Gen 4. However, I would be quite happy to see that my single poor autonomy experience is just a statistical outlier - possibly explained by accumulated small factors - and that other Gen 5 riders get an equivalent performance+autonomy to the older Gen 4s. Hence this thread and everyone's useful comments so far

Sadly I don't understand German, so I can't follow the conclusions in the two YT videos. Can anyone summarise?

The 20% higher drag claim is from different tests done on yt where testers talked about significant higer drag at the same pressure numbers, also on this forum

Schwalbe radial tyres

Look interesting, any information other than what's on the Schwalbe Web site? https://www.schwalbe.com/en/radialtires-mtb

www.emtbforums.com

there is a thread about them, on a another forum there was a user asking specifically of increased battery consumption with the radials(will try to find it later).

The conclusions of the two tests in the videos are:

On the 1st test he rides the same hill in Turbo mode until the battery is at flat 0%. The goal is max possible altitude gain. On the way down the motor is aways off.

The first video test results:
Altitude gain 1605m
Distance uphill 20,7km
Average cadence 90rpm
Average speed 18,9kmh

The second test is the same in Turbo mode until flat 0% battery but the goal here is distance, not altitude gain.

The second video test results:
Distance 79,3km
Altitude gain 396m
Average cadence 76rpm
Average speed 23,7kmh

Note: in both tests he is using the Bosch factory settings.

I am not ruling out a faulty battery in your case, but am pretty sure the main culprit here were the Schwalbe radials at really low pressure. As all the tests I have seen, the users had a tendency to over inflate compared to ther previous normal pressures.

Update: forgot to also mention that the Schwalbe radials are avaliable only in soft or ultra soft compound and they are quite heavy, could also be up to 1,5kg(depending on the casing), all of of course kills efficiency.

nickf · Mar 11, 2025

emtbeast said:
The 20% higher drag claim is from different tests done on yt where testers talked about significant higer drag at the same pressure numbers, also on this forum

Schwalbe radial tyres

Look interesting, any information other than what's on the Schwalbe Web site? https://www.schwalbe.com/en/radialtires-mtb

www.emtbforums.com

there is a thread about them, on a another forum there was a user asking specifically of increased battery consumption with the radials(will try to find it later).

The conclusions of the two tests in the videos are:

On the 1st test he rides the same hill in Turbo mode until the battery is at flat 0%. The goal is max possible altitude gain. On the way down the motor is aways off.

The first video test results:
Altitude gain 1605m
Distance uphill 20,7km
Average cadence 90rpm
Average speed 18,9kmh

The second test is the same in Turbo mode until flat 0% battery but the goal here is distance, not altitude gain.

The second video test results:
Distance 79,3km
Altitude gain 396m
Average cadence 76rpm
Average speed 23,7kmh

Note: in both tests he is using the Bosch factory settings.

I am not ruling out a faulty battery in your case, but am pretty sure the main culprit here. were the Schwalbe radials at really low pressure. As all the tests I have seen, the users had a tendency to over inflate compared to ther previous normal pressures.

Very interesting. Thanks for this useful info. I wouldn't disagree with your conclusion

Rando_12345 · Mar 11, 2025

emtbeast said:
On the 1st test he rides the same hill in Turbo mode until the battery is at flat 0%. The goal is max possible altitude gain. On the way down the motor is aways off.

The first video test results:
Altitude gain 1605m
Distance uphill 20,7km
Average cadence 90rpm
Average speed 18,9kmh

I just want to point out, in case some people get the wrong idea, that those numbers are an absolute best case scenario. The rider is 70kg, on a lightish (but not extreme) 21kg ebike with fairly light and fast rolling tyres (rear hans dampf supertrail). His numbers for the Bosch gen5 are:
600Wh -> 1600m
800Wh -> 2130m

Knowing a bunch of riders on Bosch 4th gen and myself on 5th gen motor, all around 70-80kg range, we have always gotten around 25% less climbing than in those videos. I don't really know how he manages to get the altitude gains in his videos, I'm guessing the route he is using is very hardpacked and allows for very consistent, uninterrupted high RPM, also notice the very short distance numbers. But definitely don't expect to climb that much in any kind of real eMTB ride.

Anecdotally, I havn't found a rear albert radial to have any meaningful impact on my range, but I run it fairly high pressure and it replaced a much knobblier tyre.

emtbeast · Mar 11, 2025

Rando_12345 said:
I just want to point out, in case some pople get the wrong idea, that those numbers are an absolute best case scenario. The rider is 70kg, on a lightish (but not extreme) 21kg ebike with fairly light and fast rolling tyres (rear hans dampf supertrail). His numbers for the Bosch gen5 are:
600Wh -> 1600m
800Wh -> 2130m

Knowing a bunch of riders on Bosch 4th gen and myself on 5th gen motor, all around 70-80kg range, we have always gotten around 25% less climbing than in those videos. I don't really know how he manages to get the altitude gains in his videos, I'm guessing the route he is using is very hardpacked and allows for very consistent, uninterrupted high RPM, also notice the very short distance numbers. But definitely don't expect to climb that much in any kind of real eMTB ride.

Anecdotally, I havn't found a rear albert radial to have any meaningful impact on my range, but I run it fairly high pressure and it replaced a much knobblier tyre.

Good points, that I can completely agree with, imo the biggest factor for his numbers is hardpacked terrain and consistent rpm, the rest u mentioned just slightly adding to it.
A huge hit on system/battery efficiency is a lot of stop and go in blocked terrain when climbing, a lot of tests/ers miss this point or don't do tests of this kind.

The radials are not supposed to be taken as a bad tyre.

A radial tyre with a reasonably light casing(comparable with a Maxxis EXO+ or DD) and a good rolling thread(Schwalbe Albert Radial) has imo one significant advantage. If you want to increase your efficiency u can still increase your pressure to a higher number and still benefit from better rollover, grip and damping properties of the radial tyre.
This is not possible with a non radial tyre.

Maybe the first try unintentional mistakes by testers were using the same pressures they were used to and so a lot of reports of high drag etc...

RobCZE · Mar 23, 2025

Hey guys. I had previous bike haibike fullseven 10 (bosch gen 2? Presmart?) 625wh battery. I bought new Cube SH one44 AT (2025) which is bosch gen 5. Iam so dissapointed with motor effinency and range... I can barely get what i get with unlocked 620wh battery and the biggest difference with new bosch i work my ass off twice more... I dont even use turbo or emtb mode to get range of previous bike....

nickf · Mar 23, 2025

RobCZE said:
Hey guys. I had previous bike haibike fullseven 10 (bosch gen 2? Presmart?) 625wh battery. I bought new Cube SH one44 AT (2025) which is bosch gen 5. Iam so dissapointed with motor effinency and range... I can barely get what i get with unlocked 620wh battery and the biggest difference with new bosch i work my ass off twice more... I dont even use turbo or emtb mode to get range of previous bike....

Please excuse me if what I am about to say is so obvious, but when I test rode the Vala I initially experienced the same very dramatic lack of support from the Gen 5 motor and had to put much more effort in compared to the Gen 4 on my Rail. However, since my Gen 4 is also pre-smart I had no previous experience with the Bosch app or tuning the motor mode parameters. So I downloaded the app and found that all the power support parameters on the Vala were set to zero (out of -5 to +5). So I reset the settings to +5 and sure enough the motor support was now subjectively the same as on my Gen 4 Rail.

If you have a pre-smart motor you may not be aware of the need to check and re-set the motor parameters to your personal preference. This might explain why you need to put in so much more work on the Gen 5?

Having said that, if your settings are such that the motor is given you less support than you were used to on your Haibike then you would expect to get proportionally more range from the new bike

RobCZE · Mar 23, 2025

Hey man, no need to excuse. Sure i have flow+... I set everything to 0. Than to 5. With 5 assist/dynamics is more punchy but effinency barely changed. Tried even AUTO with 0/0 and 5/5 fairly best mode on gen 5. Punchy and responsive even in 0. My real problem is effinency. I rode today eith 223m el. Gain / 20km ride i was 32% off battery and i rode in 10 degree with 50% eco / 35 % tour+ % 10% emtb / 5% turbo. Iam just hopeless! With haibike i can do the same on turbo with less battery drain.

Scuirus · Mar 23, 2025

Gen4 and Gen5 are using different battery cells, Gen2 18650, Gen3 21700. I have been involved in developing battery packs for low temperatures ranging from -40 C to 0 C. Different cell technologies can have very different low temperature performance even if they have the same capacity at +25 C. 21700 cells typically have lower internal resistance than 18650 cells. With the same current draw 18650 will have larger internal heating due to the current drawn, this will increase the usable capacity at low temperatures. So both the cell technology and cell size will influence the performance in cold weather.

nickf · Mar 23, 2025

Scuirus said:
Gen4 and Gen5 are using different battery cells, Gen2 18650, Gen3 21700. I have been involved in developing battery packs for low temperatures ranging from -40 C to 0 C. Different cell technologies can have very different low temperature performance even if they have the same capacity at +25 C. 21700 cells typically have lower internal resistance than 18650 cells. With the same current draw 18650 will have larger internal heating due to the current drawn, this will increase the usable capacity at low temperatures. So both the cell technology and cell size will influence the performance in cold weather.

That's very interesting info. But if the 18650 cells get hotter - and thereby have more usable capacity - with the same current draw, doesn't this represent power lost to heating rather than going into the motor? If so. then to achieve the same motor power with both cell types you would need to draw more current with the 18650s. This would effectively negate any capacity advantage?

RobCZE · Mar 23, 2025

I was checking i have bosch gen 4 non smart. What about bluetooth? Its possi

nickf said:
That's very interesting info. But if the 18650 cells get hotter - and thereby have more usable capacity - with the same current draw, doesn't this represent power lost to heating rather than going into the motor?sry

Scuirus said:
Gen4 and Gen5 are using different battery cells, Gen2 18650, Gen3 21700. I have been involved in developing battery packs for low temperatures ranging from -40 C to 0 C. Different cell technologies can have very different low temperature performance even if they have the same capacity at +25 C. 21700 cells typically have lower internal resistance than 18650 cells. With the same current draw 18650 will have larger internal heating due to the current drawn, this will increase the usable capacity at low temperatures. So both the cell technology and cell size will influence the performance in cold weather.

Sry i was checking have bosch gen 4 non smart.. Its 2021 bike.

Scuirus · Mar 23, 2025

Gen4 Smart and non smart are both using 18650 cells.

This is an example of usable capacity at different temperatures. When the cell is self heating in low temperatures the usable capacity will increase.

Hugal · Thursday at 11:28 PM

Hello, for those who have noticed a decrease in their range, do you know what settings do you have for your lights and do you have an electric derailleur?
I'm suprised because I rode an Orbea wild with the new drive unit and the 600Wh battery and I easily clear over 1200m of D+ and 30km in very muddy conditions in emtb mode.
Even if your bike is not light equiped, the drive unit has a voltage light setup which correspond to an european directive and which doesn't represent the power of the light but the Wh which will stay for the light when the battery will be drain for the drive unit. The higher is this setting, the lower is your range.
You have almost the same setting for electric derailleur so you can chose how many Wh will remains after the drive unit shutt off to continue to use your derailleur.
I made several scenario on the Bosch range calculator and these setting could represent until 12km in turbo mode on the range which is pretty consequent!

Hugal · Thursday at 11:47 PM

I forgot to say, you can check these setting only on the Bosch diag tool at your LBS, not in the phone app.

emtbeast · Friday at 8:44 AM

Hugal said:
Hello, for those who have noticed a decrease in their range, do you know what settings do you have for your lights and do you have an electric derailleur?
I'm suprised because I rode an Orbea wild with the new drive unit and the 600Wh battery and I easily clear over 1200m of D+ and 30km in very muddy conditions in emtb mode.
Even if your bike is not light equiped, the drive unit has a voltage light setup which correspond to an european directive and which doesn't represent the power of the light but the Wh which will stay for the light when the battery will be drain for the drive unit. The higher is this setting, the lower is your range.
You have almost the same setting for electric derailleur so you can chose how many Wh will remains after the drive unit shutt off to continue to use your derailleur.
I made several scenario on the Bosch range calculator and these setting could represent until 12km in turbo mode on the range which is pretty consequent!

Good

points, If I understood correctly the settings that are set in the software are basically reserved Wh of the battery for the light and electric derailleur that you can't use for the motor?

Bogdan_CH · Friday at 9:35 AM

Sorry to hack the thread but just had my first proper ride with my CX5 bike ( Mondraker Crafty) and noticed one thing. After you activate the motor/ pedal , if you let it standing, it makes like a faint whine, like the motor is being engaged or preparing for it to run. Seems normal but I'm wondering if others have noticed this ?

nickf · Friday at 10:57 AM

Bogdan_CH said:
Sorry to hack the thread but just had my first proper ride with my CX5 bike ( Mondraker Crafty) and noticed one thing. After you activate the motor/ pedal , if you let it standing, it makes like a faint whine, like the motor is being engaged or preparing for it to run. Seems normal but I'm wondering if others have noticed this ?

I don't have a Gen 5, but if you mean the faint whine after you press and release the pedal then it also does it on my Gen 4. Lasts 1 or 2 seconds, then stops. Normal.

emtbeast · Friday at 12:40 PM

Not really related to the Bosch motor, but the Giant Syncdrive motors have the same behavior, the explanation there is that it's a zero cadence motor, basically means the sensor for motor engagement doesn't need any pedaling cadence just pressure for it to engage. I don't own a Bosch motor, so can't compare or say anything about your experience, but also interested into the Mondraker so following

Hugal · Friday at 2:39 PM

emtbeast said:
Good points, If I understood correctly the settings that are set in the software are basically reserved Wh of the battery for the light and electric derailleur that you can't use for the motor?

Right

Bogdan_CH · Friday at 7:55 PM

Thanks for the great feedback guys, though it was something normal but wanted to be sure. Had the first proper ride today and the bike is a blast. Rode around 1100 of vertical with 51% battery, only EMTB or Boost, let's say 50/50. The 800wh is more than enough for my 85 kgs. Will look for a 600wh battery for shorter rides, even though I don't feel the weight (24 kg with Mallet E size M/L)

Bosch Gen 5 efficiency?

Member

Active member

Member

Well-known member

Active member

New Member

Member

New Member

Member

Member

New Member

Member

New Member

New Member

Active member

Member

Member

Active member

New Member

Member

Similar threads

EMTB Forums