Is there a way to calibrate the Purion?

The source is an official response of a Bosch employee.
He expected the law to be changed in the future... etc.

And with my limited knowledge; I don't now any other german-e-bike-engine brands.
Stromer is Swiss for instance.
 
Bosch may not officially support the Nyon in the US, but many of us "US" riders are using it. The nyon, app and maps all work fine in the US. Bosch has even removed the download/update restrictions on the app, so you no longer have to "jump through hoops" to get everything working. Upgrading from the Intuvia to the Nyon on my Gazelle Arroyo is one of the best decisions I have made.
Does that include the Custom Ride modes, eg. are they easy to setup now in the US?
 
Ooh, you know, I've checked the speed against my GPS but not the distance. I should do that. I assumed that the 10% overestimation meant that my "Bosch-mileage" is 10% shorter, but it would be interesting to see if this is actually the case. Though since the Purion doesn't report fractions of a mile this would be pretty tough to check other than on a long ride, and even then it there would be a lot of slop.
Good afternoon.
Today is something of a milestone in that I have cycled during this lockdown now 500 miles in shortish rides on my Cannondale Synapse Neo 1. What a lovely bike in all respects so far. However I decided to put on the new bike my old bike computer from my Ridgeback touring bike. This was in addition to the Purion computer that comes with the Synapse. I set up the computer measuring the wheel distance etc etc ( a job I have done over the years many times). I decided to add this second computer as it gave me the time and max speed and a few other things that the Purion didn't.

However on the first ride out there was a considerable discrepancy over the two read outs on travelling speed and overall distance travelled. I then spent the next 6 to eight rides adjusting the old computer to endeavour for it to synchronise with the Bosch Purion as I saw no way to mess or alter that. What a carry on until I have a very very similar read out on speed . It is very difficult whilst moving to look at two small computer screens at the same time and avoiding the pot holes in the road. I believe both are now more or less reading identical values so I am quite happy.
It is interesting to read from the above posts how Bosch may well err on the side of caution with respect to the law of the land in that their sety up may be slightly more generous in the values.
Anyway for the sake of the odd half mile in terms of total distance travelled and or the 1 0r 2 % difference in the speed readouts I am quite happy.

Just to add to the mix when out with my wife her computer on her ebike gives a different reading too. So we have between us 3 choices when we get home on the distance travelled. Hey ho what the Hell?
Anthony
 
I'm having the same issue. The Bosch motor support cuts out at 19.9 on the Bosch display (but both the Cannondale app and a Wahoo Roam show 18.
Grrrrr.
 
Interesting, I have the Purion on my bike and also use Strava on my cellphone. Strava consistently reports lower mileage than the Purion, about a mile for every 30 miles.
 
My experience and opinion here...

I ride the Cannondale Synapse Neo 1 and my Bosch unit shows a speed that is 4 km/hr faster than the actual riding speed (referencing both Wahoo GPS and a Wahoo Speed sensor mounted to front wheel). I have also referenced back to others when on group rides. The Bosch unit registers an incorrect speed and as a result, pedal assist cuts out much to soon. In Canada pedal assist is up to 32 km/hr. Pedal assist on my Bosch system cuts out at 26 km/hr.

I won't be buying another ebike in the future if it has a Bosch system. I've wasted a great deal of time going back and forth between Cannondale and Bosch while working with my Cannondale dealer bike shop. Bosch customers should have a way of tuning their bikes within the legal limits, ensuring that our bikes perform to spec and are safe. This is a Bosch issue. It's absolutely no surprise to me that people are resorting to tuning devices that make bikes much more unsafe. Because Bosch don't provide customers (users) a way of tuning their own bikes within legal limits, they are helping to create the problem that they're trying to prevent, which is illegal bike tuning. It's a ridiculous situation for the end user.
 
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I'll be getting a dealer diagnostic.
I went down this road with my local Cannondale dealer (bike shop). The diagnostic showed no issues. I assured them that there was a definite issue with the speed being registered by the Bosch head unit. Cannondale says the system is to spec and it's a Bosch system issue, while Bosch say that it's the responsibility of Cannondale to adjust any settings. It's the never ending back and forth we all detest.
 
The Bosch unit registers an incorrect speed and as a result, pedal assist cuts out much to soon. In Canada pedal assist is up to 32 km/hr. Pedal assist on my Bosch system cuts out at 26 km/hr.
Did you buy a "Canadian Bosch ebike", Euro or Aussie?
If the wheel circumference is dialed in correctly then it's behaving =exactly= like mine in that it cuts out at 26km/h but, i'm in Australia and our limit here is 25km/h.
If you did buy a Canadian Bosch ebike then possibly it somehow is not setup as a Canadian Bosch ebike (32km/h) and your local dealer does not sound too knowledgeable about it all.
If changing the wheel circumference does not affect the current speed display at all then there's a definite problem.
 
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Bosch customers should have a way of tuning their bikes within the legal limits, ensuring that our bikes perform to spec and are safe.
If in your situation (whatever is going on there?) Bosch allowed you to set your bike to how you want it now, how it is behaving now, then they would be allowing people to tune their bikes to be 6km/h faster, that's not quite what i'd call tuning within legal limits.
eg. this would allow me to almost tune mine to circumvent Australian limits (25km/h) and have Canadian limits (32km/h).
Your bike is not right, something wrong somewhere, numbers are all over the place. Not normal for a Bosch ebike.
 
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If in your situation (whatever is going on there?) Bosch allowed you to set your bike to how you want it now, how it is behaving now, then they would be allowing people to tune their bikes to be 6km/h faster, that's not quite what i'd call tuning within legal limits.
eg. this would allow me to almost tune mine to circumvent Australian limits (25km/h) and have Canadian limits (32km/h).
Here's what I think re. this... if Bosch trust the bike shops to make any necessary settings adjustments then afford the same process to individuals who sign all the necessary liability documents. I'm more than capable of connecting my bike to a computer and web portal where I can run diagnostics and adjust things manually. I think in my case though, after having run through this process with the bike shop, I'm looking at a hardware issue with the sensors. All the data input seems to have been entered correctly, then checked and rechecked.
 
Did you buy a "Canadian Bosch ebike", Euro or Aussie?
If the wheel circumference is dialed in correctly then it's behaving =exactly= like mine in that it cuts out at 26km/h but, i'm in Australia and our limit here is 25km/h.
If you did buy a Canadian Bosch ebike then possibly it somehow is not setup as a Canadian Bosch ebike (32km/h) and your local dealer does not sound too knowledgeable about it all.
If changing the wheel circumference does not affect the current speed display at all then there's a definite problem.
The bike was purchased in Ontario, Canada through an authorized Cannondale dealer.
 
The bike was purchased in Ontario, Canada through an authorized Cannondale dealer.
If changing the wheel circumference does not affect the current speed display at all then there's a definite problem.
eg. Get the dealer to try some large & small circumference values & see if it makes any difference to the speed display.
 
OEMs calculate and program the wheel circumference for their eBikes. They all seem to use a slightly different method to calculate this value before programming. Some use a theoretical size, some use a general, average-weighted roll-out, and others use a very complex formula that we are not privy to.

Sometimes, the value they come up with is good in theory, but can lead to slightly inaccurate readings in the field. Other times, the devices being used for comparison can be slightly inaccurate. Every so often, we see a situation where the OEM used the wrong value at the factory, resulting in far too much discrepancy.
 
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