Why are Bosch motors only 250 watts?

[Stefan Mikes]

My Vado SL is very whiny

Ras: You have to demo ride a full power Vado once. Not to buy it; just to understand what "silent mid-motor" really is

 

[MartsEbike]

Once again Bosch owners trying to justify why their bikes are low power and making all sorts of excuses for it...

You don't find this with Shimano or Brose owners, its always Bosch...

Bosch is the Apple of the ebike world.....

 

[Rás Cnoic]

Ras: You have to demo ride a full power Vado once. Not to buy it; just to understand what "silent mid-motor" really is

Yes, I would really like to! Plus to see how it takes on my B**tard hills

 

[rich c]

Remember us lazy Americans the next time Europe needs saved

Americans born in the teens and 20s were a lot different people than the ones born in 2000s. The men that went to WWI and WW!! were from a mainly agrarian society. Self sufficient and where physical effort put food on the table. The average male in 1940 weighed around 155 pounds, in 2020 it was 200 pounds. That speaks volumes.

 

[Stefan Mikes]

Bosch is the Apple of the ebike world.....

Word!

 

[Johnny]

As for the OP's point, here's a couple amateur and unscientific comparison vids that show right off that Bosch (or other brand name) motors can often match and out perform other higher "paper rated' motors. The first vid is a Bosch vs bbs02 - the bbs02 is supposed to be rated for 120Nm and 750w up to 1450w peak output. In the second video, the TQ HPR 120s is very similar to the Big Bafang Ultra in paper spec, but you can see it's still only in the upper-middle of the pack in real world testing. Paper numbers don't tell the whole story - and those guys have a bicycle dyno they have been testing on as well in a couple of articles (haven't seen videos posted yet).

Let me again re iterate, for emtb applications mainstream motors are great, they are built for that. In technical climbs it is not only about the amount of power, it is also how it is delivered.

Also I agree that some of the Chinese motors have inflated specs. They do it because of lack of regulations. However there are also motors that do deliver their promised outputs.


The first video is nonsense. It compares a walmart level bike with a crappy $50-80 coil suspension fork, unadjusted rear suspension with a bbs02(the maker of the video also mentions how bad the suspension on that bike is) to a Focus which is a pretty good quality mtb with good suspension components and they take the bikes to a semi-technical climb. If you take a good look the kid is struggling not because of power but because incapability of the bike itself when he hits obstacles and the guy with the focus says that he is pushing and his heart rate is in the 170's. (Also bosch brose etc are quite better motors than bbs02).

The EMTB networks one is a "technical climb". If you check his test video on TQ motor he clearly mentions that on a smooth climb TQ is very powerful and hits the speed limit easily and keeps it.
But he tests the bikes on a technical climb hence that additional power is not bringing much to the table and it boils down to how the power is regulated. And once more he doesn't dyno them. For high speed applications on smooth roads dyno matters!


Below is a comparison of a Levo with a top of the line Brose which is very similar to bosch cx in terms of power and its torque rating is a bit higher (again torque ratings without cadence is not very meaningful) with a Luna X1 which comes with m600 and pretty decent components.

The power comparison starts at 2:40 and see how much faster Luna X1 is yourself.

Comparing motors for power is really not hard. On the bench get a roller based indoor trainer and power pedals. In real world take the bikes to a smooth road climb, keep the bikes in the cadence where they claim to give their rated output and ride them with a power pedal.

 

[tomjasz]

Bosch is the Apple of the ebike world.

Perfect! I'm firmly in that camp too. AirTag, iPad, iPhone, Macbook, and iWatch. ALL incredibly reliable

 

[Stefan Mikes]

Who does the Luna repairs and handles the warranty, Johnny?

 

[tomjasz]

Who does the Luna repairs and handles the warranty, Johnny?

What warranty?

"warranties are available for 6 months and 1 year for an added cost"

 

[theemartymac]

Let me again re iterate, for emtb applications mainstream motors are great, they are built for that. In technical climbs it is not only about the amount of power, it is also how it is delivered.

Also I agree that some of the Chinese motors have inflated specs. They do it because of lack of regulations. However there are also motors that do deliver their promised outputs.


The first video is nonsense. It compares a walmart level bike with a crappy $50-80 coil suspension fork, unadjusted rear suspension with a bbs02(the maker of the video also mentions how bad the suspension on that bike is) to a Focus which is a pretty good quality mtb with good suspension components and they take the bikes to a semi-technical climb. If you take a good look the kid is struggling not because of power but because incapability of the bike itself when he hits obstacles and the guy with the focus says that he is pushing and his heart rate is in the 170's. (Also bosch brose etc are quite better motors than bbs02).

The EMTB networks one is a "technical climb". If you check his test video on TQ motor he clearly mentions that on a smooth climb TQ is very powerful and hits the speed limit easily and keeps it.
But he tests the bikes on a technical climb hence that additional power is not bringing much to the table and it boils down to how the power is regulated. And once more he doesn't dyno them. For high speed applications on smooth roads dyno matters!


Below is a comparison of a Levo with a top of the line Brose which is very similar to bosch cx in terms of power and its torque rating is a bit higher (again torque ratings without cadence is not very meaningful) with a Luna X1 which comes with m600 and pretty decent components.

The power comparison starts at 2:40 and see how much faster Luna X1 is yourself.

Comparing motors for power is really not hard. On the bench get a roller based indoor trainer and power pedals. In real world take the bikes to a smooth road climb, keep the bikes in the cadence where they claim to give their rated output and ride them with a power pedal.

The Luna is a custom bike, not an off the shelf dealer serviceable model. You can't walk in any major LBS in the country and walk out with one at will.

But I agree that they are a good example of what can be built if you want to go the custom delimited route. Along with the WW Hydra, Frey AM100, etc. etc. But those are all rare and niche bikes for a highly limited market, and most still come in heavier and slower in mixed technical use than the big names.

I have an affordable ultra powered hardtail and love it to death - after I modded it - but it serves my one main need perfectly (High-speed long-distance commuting). It is marginal to terrible in all other XC and MTB style riding. That Haibike with the TQ120 looks great, but at over $10K CAD it's not going to happen and it's still a unicorn with no local support network. And a near 60lb ebike is still going to be a no-go for at least half of the mtb community that aren't 175lb+ men.

Hopefully motors like that and the ultra begin to see more widespread adoption in the markets that allow/support them so we can see them a wider range of lightweight and technically proficient platforms, but until that happens, they are still largely relegated to the custom & modder category.

 

[PedalUma]

First off, lets not forget this is the middle of the night on an internet discussion forum (Here in Canada), so if you want scientific reference material you are in the wrong place! lol

The OP essentially asked why Bosch makes wimpy motors when the Chinese are killing it. And the short answer is - they're really not. They're each using their own marketing speak for their own reasons, and there is no true standard to compare them against at the moment. There are plenty of interesting if anectodical threads on Endless Sphere, Reddit, Pinkbike, etc. if you have time to waste.

As for the OP's point, here's a couple amateur and unscientific comparison vids that show right off that Bosch (or other brand name) motors can often match and out perform other higher "paper rated' motors. The first vid is a Bosch vs bbs02 - the bbs02 is supposed to be rated for 120Nm and 750w up to 1450w peak output. In the second video, the TQ HPR 120s is very similar to the Big Bafang Ultra in paper spec, but you can see it's still only in the upper-middle of the pack in real world testing. Paper numbers don't tell the whole story - and those guys have a bicycle dyno they have been testing on as well in a couple of articles (haven't seen videos posted yet).

Good discussion everyone. I do not want an illegal electric motor cycle. Wrap your head around another way of thinking about the Watt number. The higher the nominal the nominal number, the less efficient, usually. Do you want ten 100W incandescent lightbulbs burning off your battery or four 30W LEDs to produce the same light. The bigger number is not better - it demonstrates expenditure in the red and not investment in moving ahead.

 

[Alaskan]

Good discussion everyone. I do not want an illegal electric motor cycle. Wrap your head around another way of thinking about the Watt number. The higher the nominal the nominal number, the less efficient, usually. Do you want ten 100W incandescent lightbulbs burning off your battery or four 30W LEDs to produce the same light. The bigger number is not better - it demonstrates expenditure in the red and not investment in moving ahead.

I have yet to detect, to the touch, any increase in temperature on a Bosch motor, even on a long summer climb in the Cascades. It always seems to run cool. In three + years of riding, over 20,000 miles, the only problem I have ever had with one was fixed by tightening the mounting bolts. I am a happy captive of the Bosch ebike ecosystem.

 

[tomjasz]

Every one of the dozen different kits I’ve owned and sold as well as every proprietary motor powered bike has made me smile. Smiling almost as intensely as a hippy on psychedelics.

love the one you ride.

my only objections are over the nutters running some, one?, reseller. Spewing BS and claiming the high ground. There is no high ground. Just folks adopting eBikes.

 

[BruinMan]

I really don’t understand the question why only 250 watts? What are you looking for? You need something more powerful, then ride a motorcycle. Maybe you haven’t test ridden an eBike; please do and find out how the motor helps out. The Bosch is a well established motor system for eBikes. We don’t really need more watts to help us pedal assist. Any more watts will reduce how many miles we can travel.

 

[PedalUma]

I really don’t understand the question why only 250 watts? What are you looking for? You need something more powerful, then ride a motorcycle. Maybe you haven’t test ridden an eBike; please do and find out how the motor helps out. The Bosch is a well established motor system for eBikes. We don’t really need more watts to help us pedal assist. Any more watts will reduce how many miles we can travel.
https://youtube.com/playlist?list=RDCMUCxVMLv0XwgrIvWBjf4lWRBA.
This will help you understand how powerful the Bosch motor is.

"A pro climber will probably average about 350 to 375 watts on the climb up the Col du Tourmalet. An ordinary rider would generate closer to 175 to 200."Oct 19, 2020
So, that 175 to 200 number is added to the 250W of the Bosch bringing the total to more than that of a pro, with a figure of about 440W entering into the gears. What if you could outperform an Olympian? Cool.
Good bikes do not expend your battery like a drunken sailor on a shore leave spree.

 

[Alaskan]

I really don’t understand the question why only 250 watts? What are you looking for? You need something more powerful, then ride a motorcycle. Maybe you haven’t test ridden an eBike; please do and find out how the motor helps out. The Bosch is a well established motor system for eBikes. We don’t really need more watts to help us pedal assist. Any more watts will reduce how many miles we can travel.
https://youtube.com/playlist?list=RDCMUCxVMLv0XwgrIvWBjf4lWRBA.
This will help you understand how powerful the Bosch motor is.

Spot on comment but the link shows as unviewable on youtube.

 

[Johnny]

Once again Bosch owners trying to justify why their bikes are low power and making all sorts of excuses for it...

You don't find this with Shimano or Brose owners, its always Bosch...

Bosch is the Apple of the ebike world.....

Unfortunately most of the time this is true. For these people 249W is underpowered 251W is a moped because bosch advertises 250w nominal. If tomorrow bosch comes with a 700W nominal motor you will see the same obsessive fans singing a different song.

Not all of the owners are like these people though, There are members who also own different ebikes having different power levels including bosch mid drives and they never come and try to make these justifications. Instead they enjoy their different bikes for different use cases.

Once again the answer to op's question is, all of the mainstream companies do 250W nominal because that is the legal limit in their major market EU. As simple as that.

Btw Human beings are actually capable of quite high power outputs. See how much these guys average on a sprint challenge:

 

[MartsEbike]

The irony of this is we all know big brand motors are peaking way above 250w.... But lets keep playing the "why do you need more power" game.

 

[MartsEbike]

Unfortunately most of the time this is true. For these people 249W is underpowered 251W is a moped because bosch advertises 250w nominal. If tomorrow bosch comes with a 700W nominal motor you will see the same obsessive fans singing a different song.

Not all of the owners are like these people though, There are members who also own different ebikes having different power levels including bosch mid drives and they never come and try to make these justifications. Instead they enjoy their different bikes for different use cases.

Once again the answer to op's question is, all of the mainstream companies do 250W nominal because that is the legal limit in their major market EU. As simple as that.

Btw Human beings are actually capable of quite high power outputs. See how much these guys average on a sprint challenge:

Yeah this is true. If the law changed tomorrow everyone on this site would be upgrading before long... Despite their early protestations otherwise.

I must say I only really poke fun at the Bosch crowd because they so often see themselves in competition with the Bafang Ultra... Its weird given they're two different beasts, but its like each would like something the other has.... Maybe power, maybe refinement.... who knows. But it gives me the impression the Bosch crowd aren't entirely happy - something could be better, and maybe that is more power...

 

[Alaskan]

The irony of this is we all know big brand motors are peaking way above 250w.... But lets keep playing the "why do you need more power" game.

Bottom line is pretty much everyone's wattage number are BS for various reasons, mostly either marketing or compliance.

Some people ride hogs, some cafe racers, others dirt bikes. Same with ebikes...find one that matches how you like to ride. Be realistic about the trade offs....there are always trade offs. More powerful acceleration, faster heavy handed riding, gets you lower range requiring bigger, heavier motors and batteries, sacrificing nimbleness, handling and ride quality.

People get so hung up on abstract numbers instead or real life riding. Test ride the bikes.

Yeah this is true. If the law changed tomorrow everyone on this site would be upgrading before long... Despite their early protestations otherwise.

I must say I only really poke fun at the Bosch crowd because they so often see themselves in competition with the Bafang Ultra... Its weird given they're two different beasts, but its like each would like something the other has.... Maybe power, maybe refinement.... who knows. But it gives me the impression the Bosch crowd aren't entirely happy - something could be better, and maybe that is more power...

I am actually quite happy with my gen 4 bosch motors and still like my Gen 2s I ride for different reasons than do you and really do not feel the need for any more power than I have right now.