the accuracy of the controller

[popekr]

My husband and I both have TREK bikes. He has a Alliant and I have the verve. Both are pedal assist only. My bike through the trek app records the miles. His records the speed and miles right on the controller and he can see them in real time. I have to use the app other wise I don't have any of that.
I am wondering how accurate the controllers are with regard to speed and milage. We were riding side by side and my app and his controller read different speeds which I think would also affect the recording of accurate milage. Is there a way to calibrate these? I have a Garmin GPS which we often take and I am assuming it's the most accurate at recording milage, however it only does milage, top speed and average speed. Just wondering how this all works.
Thanks
Renee

 

[HumanPerson]

Welcome to the forums!

 

[popekr]

Welcome to the forums!

Thank you.

 

[popekr]

Well I got my answer. The accuracy is not great. I have a small route that I have calculated the milage on my Garmin and the bike says it's 4 miles longer than it actually is. Not sure if it's able to be calibrated but that part of the app is then useless.

 

[popekr]

Well I got my answer. The accuracy is not great. I have a small route that I have calculated the milage on my Garmin and the bike says it's 4 miles longer than it actually is. Not sure if it's able to be calibrated but that part of the app is then useless.

Talking to no one here did the same ride today The original milage with my actual weight was listed as 12 miles for what's actually an 8.5 mile ride. Dropped my weight in the app to 100lbs it has now recorded the milage for the exact same ride as 9 miles. So Fat people go farther with this app. Just saying.

 

[HumanPerson]

Talking to no one here did the same ride today The original milage with my actual weight was listed as 12 miles for what's actually an 8.5 mile ride. Dropped my weight in the app to 100lbs it has now recorded the milage for the exact same ride as 9 miles. So Fat people go farther with this app. Just saying.

Have you tried changing the tire size?
For instance my 26" hub drive needs to be set at 28.9" in order for my speedometer on the ebike to match the GPS speedometers...
These ebikes, nothing is really written in stone...stuff is/can be different ...so different at times, even with the same kits LOL


Keep posting your findings

 

[popekr]

Have you tried changing the tire size?
For instance my 26" hub drive needs to be set at 28.9" in order for my speedometer on the ebike to match the GPS speedometers...
These ebikes, nothing is really written in stone...stuff is/can be different ...so different at times, even with the same kits LOL


Keep posting your findings up

I will try that good idea. I didn't even think of that. I really want an accurate reading of how far I go each year. I was writing it on the calendar each day I went out and then calculating each month up for a final yearly total. I was hoping the bike would do it for me.

 

[pagheca]

My husband and I both have TREK bikes. He has a Alliant and I have the verve. Both are pedal assist only. My bike through the trek app records the miles. His records the speed and miles right on the controller and he can see them in real time. I have to use the app other wise I don't have any of that.
I am wondering how accurate the controllers are with regard to speed and milage. We were riding side by side and my app and his controller read different speeds which I think would also affect the recording of accurate milage. Is there a way to calibrate these? I have a Garmin GPS which we often take and I am assuming it's the most accurate at recording milage, however it only does milage, top speed and average speed. Just wondering how this all works.
Thanks
Renee

Interesting question, but what is the error in percentage? "4 miles", but how long was the ride?

Even if you set the tire size correctly as suggested (you have to!), both the GPS and the controller will have an error. The GPS because it tends to interpolate between points taken a few seconds apart (the interpolation is a pretty complicated calculation required in an effort to minimize the position error using several assumptions) and you are not riding on a straight line, AND also because there is an inherent error in each point taken that maybe of several meters (I have done several tests measuring it and comparing it with the reading from a professional GPS receiver I have, the phone and my watch). The controller because there can be some errors in the gear ratio, in the tire size (due to the tire pressure), etc. Moreover, you and your husband are not doing exactly the same route.

 

[popekr]

I will try that good idea. I didn't even think of that. I really want an accurate reading of how far I go each year. I was writing it on the calendar each day I went out and then calculating each month up for a final yearly total. I was hoping the bike would do it for me.

I cannot change the tire size on the app. It has my bike and won't let me change those specifics. :-(

 

[popekr]

Interesting question, but what is the error in percentage? "4 miles", but how long was the ride?

Even if you set the tire size correctly as suggested (you have to!), both the GPS and the controller will have an error. The GPS because it tends to interpolate between points taken a few seconds apart (the interpolation is a pretty complicated calculation required in an effort to minimize the position error using several assumptions) and you are not riding on a straight line, AND also because there is an inherent error in each point taken that maybe of several meters (I have done several tests measuring it and comparing it with the reading from a professional GPS receiver I have, the phone and my watch). The controller because there can be some errors in the gear ratio, in the tire size (due to the tire pressure), etc. Moreover, you and your husband are not doing exactly the same route.

I don't really understand what you are trying to say. It may be beyond by scope of expertise at the moment. Sorry. We were doing the same route, riding side by side. Are you saying that even if we do ride side by side the items read it differently?

 

[ezl]

I cannot change the tire size on the app. It has my bike and won't let me change those specifics. :-(

The Dashboard or Readout would give the model number on it which cane be looked up on YouYube or information on changing it
from the a 3-button control which controls the PAS and on/off of the Ebike. The tire size has to be right to match the speed on a GPS
in real-time. That means, getting into the advanced settings and to get into them you might need a password. The dealer might be able
to help you with that. I know that mine was way off with it's settings and a "C" came up on the display which probably means "Controller"
for advanced settings. A 4-digit code had to be entered to get to get to advanced settings. I found the code on YouTube to get to the
controller settings? Before changing any settings, make sure to write them down and some settings interact with each other. I had to use
a GPS to get my speed setting to adjust the tire size setting by trial-and-error to correct the mileage and speed of the bike. I found that
the factory settings were off more than 8 mph! Some of the settings in the menu went from P1 to P20 so be careful what you change!

 

[arthurdent18610]

My husband and I both have TREK bikes. He has a Alliant and I have the verve. Both are pedal assist only. My bike through the trek app records the miles. His records the speed and miles right on the controller and he can see them in real time. I have to use the app other wise I don't have any of that.
I am wondering how accurate the controllers are with regard to speed and milage. We were riding side by side and my app and his controller read different speeds which I think would also affect the recording of accurate milage. Is there a way to calibrate these? I have a Garmin GPS which we often take and I am assuming it's the most accurate at recording milage, however it only does milage, top speed and average speed. Just wondering how this all works.
Thanks
Renee

They vary a lot, whilst some are accurate to 1 or 2 mph others can be as much as 5 mph higher & that ofcourse effects overall milage. I had a GPS speedometer on one of my ebikes & there's a difference of 3 mph between the bikes display & the GPS, the bikes display was showing a higher speed. These flashing roads signs in the uk also showed that I was travelling slower than the bikes display. The displays readings will be effected by the wheels diameter & if your running fat tyres that too will effect the mph. In one video a fat bike display had to be set to a larger wheel diameter due to the tyres fitted. Tyre pressures are also important as this can effect the displays mph

 

[popekr]

The Dashboard or Readout would give the model number on it which cane be looked up on YouYube or information on changing it
from the a 3-button control which controls the PAS and on/off of the Ebike. The tire size has to be right to match the speed on a GPS
in real-time. That means, getting into the advanced settings and to get into them you might need a password. The dealer might be able
to help you with that. I know that mine was way off with it's settings and a "C" came up on the display which probably means "Controller"
for advanced settings. A 4-digit code had to be entered to get to get to advanced settings. I found the code on YouTube to get to the
controller settings? Before changing any settings, make sure to write them down and some settings interact with each other. I had to use
a GPS to get my speed setting to adjust the tire size setting by trial-and-error to correct the mileage and speed of the bike. I found that
the factory settings were off more than 8 mph! Some of the settings in the menu went from P1 to P20 so be careful what you change!

Thank you, this is great information. I actually have a 30 day check up coming up for the bike so I am going to talk to the sales person and the bike mechanic at the store armed with this information. much appreciated.

 

[addertooth]

The update rate varies by the quality of the GPS. For those using phones, the update rate is slow.
However, if you are cruising at a constant speed on a flat road, the value out of the GPS is the bible.
I would perform that test, and correct the wheel size on the bike to match the speed value reported by the GPS.

 

[popekr]

Well with a little bit of adjusting, hubby's bike, my bike and the GPS are all within a half mile of each other. We did 42 miles yesterday and made adjustments to the app but only needed to make me weigh 80lbs on the app to do so. We fiddled with that first rather than get to complicated and I am happy to be a smaller woman.

 

[pagheca]

Good for you both for finding a solution! However, I would be really curious to know what weight and distance traveled have to do with each other... But your husband must be a genius! I would never have fiddled with the weight to solve such a problem.

 

[ezl]

They vary a lot, whilst some are accurate to 1 or 2 mph others can be as much as 5 mph higher & that ofcourse effects overall milage. I had a GPS speedometer on one of my ebikes & there's a difference of 3 mph between the bikes display & the GPS, the bikes display was showing a higher speed. These flashing roads signs in the uk also showed that I was travelling slower than the bikes display. The displays readings will be effected by the wheels diameter & if your running fat tyres that too will effect the mph. In one video a fat bike display had to be set to a larger wheel diameter due to the tyres fitted. Tyre pressures are also important as this can effect the displays mph

I tuned mine using a Meilan GPS that I took of my 49cc gasbike and it takes time but can be zeroed in and corrected.

 

[popekr]

Good for you both for finding a solution! However, I would be really curious to know what weight and distance traveled have to do with each other... But your husband must be a genius! I would never have fiddled with the weight to solve such a problem.

Yes the weight was his idea. I actually contacted the people who designed the app. They had no good advice and blamed it on how we all connect to the satalights blah blah blah. They suggested trying another app. I've got it pretty close and I sure don't mind being 80 lbs.

 

[ezl]

Have you tried changing the tire size?
For instance my 26" hub drive needs to be set at 28.9" in order for my speedometer on the ebike to match the GPS speedometers...
These ebikes, nothing is really written in stone...stuff is/can be different ...so different at times, even with the same kits LOL


Keep posting your findings

That's very important! A trial run with a GPS, then get into the Tire Size Configuration and change it. Takes a lot of stopping and starting.
Note, all changes should reflect on a flat roadway and no wind. Getting it right to register the speed is critical with the tire size and the
distance will come out ok. A lot easier if it's done with Cruise Control (hopefully you have the function), no pedaling and there is a lag
with GPS so a flat run at a constant speed to check against the Displayed DashBoard Speed and GPS. I found 2-settings that interact
which was a pain setting the Display up. Recommend writing down ALL settings so the the Controller settings don't get screwed up!

 

[popekr]

That's very important! A trial run with a GPS, then get into the Tire Size Configuration and change it. Takes a lot of stopping and starting.
Note, all changes should reflect on a flat roadway and no wind. Getting it right to register the speed is critical with the tire size and the
distance will come out ok. A lot easier if it's done with Cruise Control (hopefully you have the function), no pedaling and there is a lag
with GPS so a flat run at a constant speed to check against the Displayed DashBoard Speed and GPS. I found 2-settings that interact
which was a pain setting the Display up. Recommend writing down ALL settings so the the Controller settings don't get screwed up!

I am not able to change the tire size unless I get into it too deep for me the bike is set up in the app and it's not really changeable and since we managed to get the GPS, hubbys bike and mine all to within a half mile or each other I thought that was good enough. I don't have cruise control. It's only a pedal assist bike and most of the time I don't have the assist on. It's only on when I really need to get the bike up a hill that I generally can't make or if I am at the end of a long ride and need a break. But thank you very much for the info. The more I know the better. The Trek app people were not helpful at all they basically said too bad and did I try any other apps as they may be more accurate.