Bit confused about the Bosch Drive Unit Performance CX

soundwave

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Soundwave, could you learn to use the "quote" key so that it makes your posts make a bit more sense.
found it :)
There is absolutely no way the authorities could measure voltage and current draw from the battery and determine the bike was legal or not as EN15194 takes into account all the drivetrain and tyre losses.
not even bosch can tell if a dongle has been used on a bike so uk police got no chance if its been removed.

not that they will bother anyway :)
 

Wisper Bikes

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Bosch were here last week for a dealer training day. One of the most discussed points was whether or not they could tell if a dongle had been fitted.

The Bosch response was that they could tell a dongle had been fitted but could not prove it. Didn't make sense then and still doesn't now.

It seems though that the fitting of a dongle does not void a warranty! I was always lead to believe it did.
 
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soundwave

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soundwave

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Is tuning permitted?
No, tuning is prohibited. If you nevertheless use a tuning kit or otherwise modify your Bosch eBike system, your eBike’s guarantee and purchase warranty will be rendered null and void. Any improper treatment of the system will generally reduce its service life and risk damage to the Drive Unit and bicycle. In addition, you endanger your own safety and that of other road users, thus risking high personal liability costs and even the possibility of criminal prosecution, in the case of accidents attributed to tuning. For these reasons, Bosch eBike Systems implores all eBike riders and providers to refrain from tuning.
https://www.bosch-ebike.com/au-en/service/faq/is-tuning-permitted/
 

Wisper Bikes

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The Bosch mechanic told us all, during training, that they could not prove whether or not a bike had been fitted with a dongle. Therefore how could they argue with anyone who having fitted a dongle, tells them (or us) that they have not?
 

soundwave

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well guess its your word against a dealers in that case as they cant prove it 1 way or the other.

ebike shop fits dongles and honers the warranty and bosch must know this but does nothing.

Any improper treatment of the system will generally reduce its service life and risk damage to the Drive Unit and bicycle.
if a dongle only removes the speed limit then that is total rubbish.
 

flecc

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What has come to light here is the the 250W rating on these motors most likely refers to mechanical output power at the wheel. There is absolutely no way the authorities could measure voltage and current draw from the battery and determine the bike was legal or not as EN15194 takes into account all the drivetrain and tyre losses.

In conclusion - as long as you are limited to 25km/h.....
And the first test option in EN15194 is almost always impractical anyway. The motor shaft isn't readily accessible for a power output check with internally geared hub motors and most crank drive units.
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flecc

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Are the 250w and 350w bosch motors exactly the same except for a different cut out speed in the software ?
Electro-mechanically yes, they are sold with the appropriate rating to match the law in the area of sale.
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flecc

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Incidentally, if you want to know how much mechanical power your ebike is really putting out, all you need to do is put your stats into this little formula....

Alternatively, PM me and I will email you the excel file.
Thanks, but already done with a different equation method. Of course the 1000 watt peak I mentioned doesn't reflect the continuous practical net power even with the efficiency loss taken into account. The actual net output power is 565 watts.
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Bosch were here last week for a dealer training day. One of the most discussed points was whether or not they could tell if a dongle had been fitted.

The Bosch response was that they could tell a dongle had been fitted but could not prove it. Didn't make sense then and still doesn't now.

It seems though that the fitting of a dongle does not void a warranty! I was always lead to believe it did.
Soundwave keeps looking at a dealer report, not what Bosch themselves can see.

and its easy for Bosch to tell when one has been used, because they can see more data than a dealer. You just have to look at the average speed of the bike and the power used, or compare battery life and mileage. Its obvious when a bike has been dongled, but is it proveable...

Fitting a dongle does void warranty, but as with everything you warranty is with the dealer not with Bosch.... its the dealers warranty that is with Bosch. So if you're nice to the dealer and your not an idiot, ie post all over the internet about how great your dongle is?
 

soundwave

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well if you think you can prove it 1 way or another if 1 has been used post the proof for everyone to see.

not 1 dealer has yet done so since i joined this forum and asked you b4 and other dealers and you have the bosch software so lets see some proof, i went in to the future and its not going to happen.;)

if Bosch could tell dongles had been used martin would have stopped fitting them long ago as im sure he is not forking out for new motors with problems with dongles fitted and getting them replaced under warranty by bosch.

and despite your last effort to stop him selling them with letters from haibike ect he still sells them tho now not on the same page as the bike.

but there still there and will still honer the warranty?

Fitting a dongle does void warranty, but as with everything you warranty is with the dealer not with Bosch.... its the dealers warranty that is with Bosch. So if you're nice to the dealer and your not an idiot, ie post all over the internet about how great your dongle is?
so that tells me i can fit a dongle dont post about it on line ect and if i do get a problem the dealer will not know anyway lol.:D
 
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not 1 dealer has yet done so since i joined this forum and asked you b4 and other dealers and you have the bosch software so lets see some proof, i went in to the future and its not going to happen.;)
We only have the dealer software, so we just get the basic report that you've posted. What I've said is that I don't think dealers can tell for sure from their data, but Bosch can because they have access to more details. I'm sure you only have to look at the average speed of the bike, or the miles its done from the battery charges to be able to show that a dongle has been used. Its obvious to us when one has been used, and we have turned down warranties because of it.

if Bosch could tell dongles had been used martin would have stopped fitting them long ago as im sure he is not forking out for new motors with problems with dongles fitted and getting them replaced under warranty by bosch.
You're confusing dealer and manufacturer again. Martin runs a shop he sells stuff to people like you. If you have a warranty you go back to him, if you've been using a dongle and he say's he'll warranty it. He can do no problem at all, your contract is with him. So he'll give you a new motor. He's probably making enough money that he can afford to do this without even going to Bosch, or maybe he does send it to Bosch, who knows. But he can say he'll warranty something for 25 years if he wants. The dealer can offer anything over and above what they are offered by the people they buy off.
 

soundwave

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well if you refuse warranty and get taken to court to prove it then you are going to have a problem then as you have no proof 1 way or the other.

The Bosch mechanic told us all, during training, that they could not prove whether or not a bike had been fitted with a dongle. Therefore how could they argue with anyone who having fitted a dongle, tells them (or us) that they have not?
if all you can do is give the report as above then you will loose :)
 
well if you refuse warranty and get taken to court to prove it then you are going to have a problem then as you have no proof 1 way or the other.



if all you can do is give the report as above then you will loose :)
Its pretty easy to prove... in the couple of cases where its been an issue, it only takes 30 seconds on Strava, Facebook or goggle to prove, because people with dongles love to post about it.
 

anotherkiwi

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Interesting. So 'peak' output of the Bosch system can actually be as high as 850W, with only the average power being 250W in 'cruise' mode as they call it.
That means they use a 20 Amp controller and it can provide that amount of power with a 36 V battery hot off the charger. The rest of the time it will peak at around 720 W - 130 W less.
 

anotherkiwi

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They are exaggerating with the word "additional". Their meaning of additional could be additional to the rider effort. :rolleyes:
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The other day on a TV "scientific show" the oldest guy - +50 - got on a fixed bike thingy attached to a meter and produced 666 W for a brief period of time (cadence 180).

If the Bosch peaks at 612 W it would be a 17 Amp controller. Ciclotek sells 17 Amp controllers for their Mxus hubs.
 

flecc

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The other day on a TV "scientific show" the oldest guy - +50 - got on a fixed bike thingy attached to a meter and produced 666 W for a brief period of time (cadence 180).
But as you say, briefly. A fully fit cyclist can continuously produce 200 watts for two or three hours, and at half or less that extreme cadence. But of course a very high proportion of e-bikers aren't fully fit, the reason for them using an e-bike, and they generally use much lower cadences than keen cyclists.
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Ray Breen

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that is interesting, ebikes aside, i personally prefer to be a in lower gear with a higher cadence.

With me waiting for my ebike to arrive, what impact does a high cadence/low gear have over a higher gear/lower cadence(bike i am getting(woosh big bear) has the motor in the front hub, so i guess is less likely to be impacted by cadence?)
 

flecc

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that is interesting, ebikes aside, i personally prefer to be a in lower gear with a higher cadence.

With me waiting for my ebike to arrive, what impact does a high cadence/low gear have over a higher gear/lower cadence(bike i am getting(woosh big bear) has the motor in the front hub, so i guess is less likely to be impacted by cadence?)
Yes, usually not really relevant with a hub motor, unless with a torque sensor on the crank..

Any system with a torque sensor is affected by cadence, since each pedal stroke pressure on the torque sensor reduces with rising cadence, affecting the assist power supplied.
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soundwave

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seen that months ago and all he did was remove them from the bike page.

m8 got a Yamaha bike last year and his dongle is inside the motor case so no easy way for him to remove it, not that he will lol.

and there is no way he is going to pay for new motors with the price off other items on his site like 150 quid more than chain reaction for a seat post.:eek:


1 thing i find odd is he does not sell motors?