Bafang M500 V2 vs Bosch Gen 4

[Rob Rides EMTB]

This motor ABSOLUTELY CRUSHES it!!

 

[RustyMTB]

Honestly amazed at the climb test outcome!

 

[Curiousman]

This motor ABSOLUTELY CRUSHES it!!

All is said.
But that's no surprise!

 

[MartinEbiker]

ok so it is better with the new software, but is there a way to upgrade it?

 

[Curiousman]

ok so it is better with the new software, but is there a way to upgrade it?

No

 

[dobbyhasfriends]

perhaps not the best ad for selling the cheeb

I finally rode the bosch gen4 recently and I was blown away, im sure its more powerful than my levo and I love the EMTB mode.

 

[Zimmerframe]

I think the M500 almost falls into a "new" category ... it's almost as pokey as a full fat, but seems to sip the power like an SL.

It's like Diet FF.. would be interesting to also see them both ridden back to back until flat on decent terrain to see how they perform.

If you think about price difference to performance difference/weight difference, it's still pretty impressive for 95% of the time/users.

 

[Zimmerframe]

perhaps not the best ad for selling the cheeb

I finally rode the bosch gen4 recently and I was blown away, im sure its more powerful than my levo and I love the EMTB mode.

Still feeling the same ? Interesting !!

Must be tricky for Spesh. They went brose because they could customise and they've done great things there. It's also given them individualism to an extent - and a quiet motor (not just when it's broken ! Better get in there before @Doomanic).

When you're buying a bike, would you buy a Levo is it was just another Bosch or ep8 bike ? OR would you just lump it in with the other choices ?

Maybe Mahle will churn something new and special out down the line and they'll use that , what though ? There's only so much you can do with current technology.

 

[Seqlat]

This motor ABSOLUTELY CRUSHES it!!

Will Cheeb V2 also be based on the Bafang engine?

 

[dobbyhasfriends]

Still feeling the same ? Interesting !!

Must be tricky for Spesh. They went brose because they could customise and they've done great things there. It's also given them individualism to an extent - and a quiet motor (not just when it's broken ! Better get in there before @Doomanic).

When you're buying a bike, would you buy a Levo is it was just another Bosch or ep8 bike ? OR would you just lump it in with the other choices ?

Maybe Mahle will churn something new and special out down the line and they'll use that , what though ? There's only so much you can do with current technology.

no, after I posted that I was thinking that it was a bit misleading.
I have my acceleration on zero on the Levo, this couldn't be altered on the bosch (so I was told) and it was extremely lively, too much acceleration and far less natural feeling.
thats just the feel of the motor on the flat. the Levo (IMO) is far far better at tech climbing in its delivery and overrun.
yes, I would deffo consider a bosch motor'd bike but I would want to tune it.

 

[Zimmerframe]

I think we take for granted a bit some of the flexibility of the Spesh setup. Even other Brose suppliers don't give any of this. Often works against them though when people don't understand the settings and have things set wrong.

The Shimano is semi tune able with stunlocker, which is great. I think you can with the Bosch but need to flash a third party firmware or swap out the controller card - sure someone else knows more, don't have any experience with it ..

There's a few other motors out there which look interesting, but don't seem to have hit any main streams, so maybe they look better on paper than they perform in real life.

 

[markus datgloi]

I hope that both CHEEB and TREK were in a corresponding gear ratio from peddle stroke to travel distance given the differences in cassette, chainring and wheel/tire size...
A dynamometer would help to measure what torque is delivered at the rear wheel.
I assume with Bafang the delivered motor torque to the human input torque ratio is realized (programmed) as a lineaire function (no punch) instead of a progressive one (punch).
Not that I would want it but what if the CHEEB had a throttle... more power with throttle ?

I conclude the M500 doesn't deliver 95nm . Or does the BOSCH deliver more ? What about the M600 claimed at 120nm ?

 

[Rob Rides EMTB]

I hope that both CHEEB and TREK were in a corresponding gear ratio from peddle stroke to rear wheel rotation given the differences in cassette, chainring and wheel/tyre size...
A dynamometer would help to measure what torque is delivered at the rear wheel.
I assume with Bafang the delivered motor torque to the human input torque ratio is realized (programmed) as a lineaire function (no punch) instead of a progressive one (punch). A throttle engine ?
Not that I would want it but what if the CHEEB had a throttle... more power ?

TBh, I just rode 2 bikes up a hill.

 

[Zimmerframe]

It might be that the M500 does put out 95nm.

It doesn't mean it puts it out in a way which is ideal for real world usability on an EMTB.

Bafang are pretty new to making EMTB motors which conform to the present regulations. I think what they've put out so far is pretty good. All the companies are improving year on year. All the motors have their plus points and their negatives the M500 and the Gen4 included.

We shouldn't forget that the Bosch Gen4 beat all the other motors when Rob tested them, so I don't think anyone should be upset if the M500 didn't beat the Bosch.

You could set both bikes up in a lab and measure things. It might be in the Lab or on paper, the M500 would be "better" than the Bosch.

It terms of real world usability in this particular test though, for a human being riding both bikes and obviously trying their hardest and selecting the most appropriate gear to try to get to the top of the hill, the Bosch was more suitable.

You might setup 10 different tests and the bafang would probably be better at some of them, range maybe for instance - the M500 seems frugal/efficient.

Talking of Frugal, I'm impressed Rob managed to hold of from swearing so long ..

 

[memtb]

Good job testing in real world situation Rob. How something does on the flat or going slow is neither here nor there.
I sometimes think something gets lost in translation with some of these products.
Lost count of the amount of chinese products you try and find real user experience about and just find endless spec sheets or
have them quoted back at you.
Actual user experience is not thought important in some places I guess.
Plus point for the bafang is you can get one and fit it to a frame you got from china at a reasonable price.
If all you want to do is tool about quoting spec sheets then its the product for you.
Funny enough there is no shortage of people that are happy to do this.

 

[Gyre]

Many thanks Rob. Interesting to see that "95 NM" got so soundly walloped by "85 NM". Goes to show that when a company makes those kinds of claims, you have to take it with a grain of salt. Maybe they don't use the same testing methods, maybe the motor just can't sustain the torque for some reason, or maybe they're just being "very optimistic" about the output.

Rob, is it fair to assume you had no problem on either bike keeping weight on the front wheel?

Anyway, loving my Bosch. I've had the surreal experience of climbing up some stuff that was so steep I didn't feel comfortable about whether I'd have enough grip riding it back down!

 

[Equilibrium]

I conclude the M500 doesn't deliver 95nm . Or does the BOSCH deliver more ?

You can not conclude that. Those torque figures are just peak values at some unknown cadence. It is possible that m500 really supply that torque at the cranks at some cadence.

What can be concluded, given gear ratios are the same, is that at very low cadences Bosch gives more power than m500 and it seems to be better suited for emtb.

 

[BootsDave]

Hey Rob, before it goes, we need you to test the Cheeb up the same hill as in the Motor Group Test. Since it was because of this test that the Cheeb was born. Don’t need a video, just the ’time‘ to see how it compares with all of the motors.

 

[Curiousman]

Has anyone ever received the "new" reinforced M500 motor? Could he indicate the serial number of this new motor to be able to tell the difference with the old version?

 

[CRFan1]

Nice Video Rob! That Bosch motor is most impressive!

 

[Gyre]

Has anyone ever received the "new" reinforced M500 motor? Could he indicate the serial number of this new motor to be able to tell the difference with the old version?

This is a great point. Someone shopping for a Bafang should have the means to know whether they're buying the newer version or not.

 

[BootsDave]

Is no one else a little bit suspicious about the sudden demise of the Cheeb? Find a hill to prove the Bosch is more powerful, then sell the Cheeb so no other comparisons can be made. Looks like some pressure was applied??? I guess we’ll all find out when we get ours!

 

[Gyre]

Is no one else a little bit suspicious about the sudden demise of the Cheeb? Find a hill to prove the Bosch is more powerful, then sell the Cheeb so no other comparisons can be made. Looks like some pressure was applied??? I guess we’ll all find out when we get ours!

The Cheeb looks like it will be great fun for the markets that can get it.

That said, I don’t have nearly enough aluminum foil to entertain the notion of a conspiracy here.

 

[markus datgloi]

One thing is clear: the Cheeb just loosing against a top spec Trek Rail is a very good result for the Cheeb. But the Cheeb has more power...
I tried to understand it by doing a simple calculation. I hope what I did is correct and please correct me where I am wrong.
What did I do ? Put all in a spreadsheet and calculate the force at the rear wheel.
I ignored any kind of loses, motor characteristics, pedal stroke, begin speed, tires, etc. I assumed the motors are as strong as claimed (Bosch 85 Nm and Bafang 95 Nm). To compare the results I set the force at the rear wheel of the Cheeb 2.0 as the reference (100%).
The calculations show:
- the difference between both is not so much, in numbers
- the Trek seems to benefit more from the added rider leg force
- by replacing the chainring of the Cheeb from 36T to 34T it could win, although it is a minimal win
- if you are willing to upgrade the cassette (plus derailleur and shifter combination) there is much more to gain for the Cheeb
- my Decoy 29 Pro (Shimano E8000 75 Nm) cannot win from the Cheeb

What if you change some numbers (yellow fields) ?
A Decoy 29 Pro with Shimano EP800 (85 Nm) and a 34T chainring and 10-52 cassette should be a match to the Trek (in numbers).
What if the Bafang is just a bit less strong as claimed (94-92 Nm) or the Bosch is a bit stronger (86-87 Nm) or both ? The Trek wins.
What if you go for the Bafang M600 with 120 Nm ? The Cheeb wins.
For a self build I will choose: 34T chainring and a 10-50 cassette.

So what would be the force delivered at the wheel ? The formula would be, with:
Fr = Rider leg force in kg
Lc = Crank length in meter
g = gravity earth 9.81 (kg to Newton)
Mt = Motor torque in Newtonmeter (Nm)
Tc = Teeth cassette (largest)
Tm = Teeth chainring motor
Fw = Force at wheel in Newton
Rw = Rear wheel radius

The total input torque is the sum from driver input and motor: (g * Fr * Lc + Mt).
What you put in in torque must come out: (g * Fr * Lc + Mt) / Tm == Fw * Rw / Tc
or (rewritten) the force at the rear wheel :

Fw = (g * Fr * Lc + Mt) * Tc / (Tm * Rw)

TREK Rail:
Cassette 10-52 (Rail 9.9) or 10-50 (Rail 5), both chainring 34T, crank lenght 0.165 mtr
wheelcircumstance Bontrager XR5 Team Issue 700c/29 x 2.60 = 2.36901 mtr, radius 0.3770 mtr

CHEEB (assuming these are the correct numbers):
SHIMANO M4100 cassette 11-46 , chainring 36T, crank length 0.170 mtr
wheelcircumstance 650b/27.5 x 2.40 inch = 2.21771 mtr radius 0.3528 mtr

Wheelcircumstance from: BikeCalc.com - How to calculate Bicycle Wheel Size
Spreadsheet (free): made with LibreOffice.

 

[Curiousman]

One thing is clear: the Cheeb just loosing against a top spec Trek Rail is a very good result for the Cheeb. But the Cheeb has more power...
I tried to understand it by doing a simple calculation. I hope what I did is correct and please correct me where I am wrong.
What did I do ? Put all in a spreadsheet and calculate the force at the rear wheel.
I ignored any kind of loses, motor characteristics, pedal stroke, begin speed, tires, etc. I assumed the motors are as strong as claimed (Bosch 85 Nm and Bafang 95 Nm). To compare the results I set the force at the rear wheel of the Cheeb 2.0 as the reference (100%).
The calculations show:
- the difference between both is not so much, in numbers
- the Trek seems to benefit more from the added rider leg force
- by replacing the chainring of the Cheeb from 36T to 34T it could win, although it is a minimal win
- if you are willing to upgrade the cassette (plus derailleur and shifter combination) there is much more to gain for the Cheeb
- my Decoy 29 Pro (Shimano E8000 75 Nm) cannot win from the Cheeb

What if you change some numbers (yellow fields) ?
A Decoy 29 Pro with Shimano EP800 (85 Nm) and a 34T chainring and 10-52 cassette should be a match to the Trek (in numbers).
What if the Bafang is just a bit less strong as claimed (94-92 Nm) or the Bosch is a bit stronger (86-87 Nm) or both ? The Trek wins.
What if you go for the Bafang M600 with 120 Nm ? The Cheeb wins.
For a self build I will choose: 34T chainring and a 10-50 cassette.

So what would be the force delivered at the wheel ? The formula would be, with:
Fr = Rider leg force in kg
Lc = Crank length in meter
g = gravity earth 9.81 (kg to Newton)
Mt = Motor torque in Newtonmeter (Nm)
Tc = Teeth cassette (largest)
Tm = Teeth chainring motor
Fw = Force at wheel in Newton
Rw = Rear wheel radius

The total input torque is the sum from driver input and motor: (g * Fr * Lc + Mt).
What you put in in torque must come out: (g * Fr * Lc + Mt) / Tm == Fw * Rw / Tc
or (rewritten) the force at the rear wheel :

Fw = (g * Fr * Lc + Mt) * Tc / (Tm * Rw)

TREK Rail:
Cassette 10-52 (Rail 9.9) or 10-50 (Rail 5), both chainring 34T, crank lenght 0.165 mtr
wheelcircumstance Bontrager XR5 Team Issue 700c/29 x 2.60 = 2.36901 mtr, radius 0.3770 mtr

CHEEB (assuming these are the correct numbers):
SHIMANO M4100 cassette 11-46 , chainring 36T, crank length 0.170 mtr
wheelcircumstance 650b/27.5 x 2.40 inch = 2.21771 mtr radius 0.3528 mtr

Wheelcircumstance from: BikeCalc.com - How to calculate Bicycle Wheel Size
Spreadsheet (free): made with LibreOffice.

View attachment 60165

Wow, what a job !!
But frankly, you only have to try the M500 motor to feel that the power (in W, not in torque) fails to express itself. I am convinced that the software settings are not optimized at all. In particular with regard to the calibration of power sensors on the pedals. I am light and as a result the motor does not realize that I am pushing hard on the pedals and it does not deliver its maximum power (in W) even in the highest mode. I have never had this problem on any other motor (Bosch, Yamaha, Shimano, brose …). Exactly like Rob, with the Bafang M500 I can't manage to climb hills that I climbed without problem with a Shimano E8000 motor (70Nm torque) and with the same 12 speed drivetrain (11-51).
But unfortunately Bafang is not listening to its users to improve them ...

 

[Gyre]

I think @Equilibrium hit the nail on the head. Even if we assume that Bafang actually measured 95nm of torque accurately before making their claim, we don't know anything about the torque curve at a particular cadence. It's possible that either the software holds back at a certain cadence or the hardware has some kind of ceiling it runs into.

 

[Rob Rides EMTB]

Is no one else a little bit suspicious about the sudden demise of the Cheeb? Find a hill to prove the Bosch is more powerful, then sell the Cheeb so no other comparisons can be made. Looks like some pressure was applied??? I guess we’ll all find out when we get ours!

/about to retire with the £1M payment that Bosch sent me ?

Of course not.... it’s simply not as powerful. Why would I make that up??

 

[dixie600mhz]

Why would anyone run the m500 instead of the m600? M600 utterly destroys Bosch Gen 4. I have both right now and alternate between the two. My fastest Strava times are from m600. The Bosch is much smoother but I'm playing with the bafang best tool now to fix that. For raw power m600. For smoothest most natural assist Bosch.

 

[Zimmerframe]

Is no one else a little bit suspicious about the sudden demise of the Cheeb?

Don't forget that Rob doesn't keep a fleet of 50 personal bikes (as far as we know).

If you apply your logic to his previous bikes - then why did he sell the STILUS and all the upgrade parts cheaply on the Forum ? It was a Bosch bike as well. Because as well as long and short term test bikes, he also buys other bikes for himself to play with and do things with.

He built the Cheeb, did a great job, probably inflated Dengu and M500 sales 100 fold - showed us all another way for £4000. Found it lacking in power and Bafang sent him the upgraded V2 version of the motor - which was better, but still not quite as good as the Bosch. He's not said it's crap ! Just not quite as good in terms of power delivery. The Cheebs going and as he said in his Video, he'll be making the Cheeb 2 - the Cheeber ?!?

It would be a bit boring if he just kept riding the same bike all the time.

 

[BootsDave]

We still don’t know how it compares. Why not run it up the same hill as the group test? At least we’d have a figure to compare. All we know is that it wasn’t as good up one really steep hill as the Bosch!