X1's Speedometer Not Accurate (It's Fast by 2 MPH)

[joegold100]

I've noticed when I started adding GPS overlays to the videos I've shot on the X1 that the speed on the digital speedometer is 2 mph faster than the speed which shows from GPS (SEE IMAGE BELOW) . As many of you are probably aware, GPS speed is usually more accurate than speedometers since GPS providers have been sued for showing speeds that were less than actual in the case of speeding tickets). I can confirm this to be true because the GPS on my phone and the speedometer in my car is nearly identical. I've made no changes to tire size or gearing on my bike.

One reason I want to adjust this is because the bike motor shuts down at 25 mph which is actually 23 mph. Anyone have any idea how we could adjust this to get it more accurate?

[joegold100]

So, I did another downhill yesterday and found out that if you go over 40 mph the speedometer flips and goes to 0!!! Check this out:

[joegold100]

So... i checked my settings and I think I figured out why the speedometer is off by 2 MPH. My wheel size is set to 28 inch but the wheels are 27.5 inch. However, the wheel size is locked and I can't edit the wheel size.

In addition, I see in the advanced settings that the Max Speed is set to 90 kph which is 56 mph. So there should be no reason that the speedometer flips when I hit 41 mph...

[KTMracer63]

1.2.18 Besst App doesn't allow decent parameter adjustments.

Using 1.2.23 firmware (NOT 1.2.26), one can adjust the parameter/firmware settings (for Wheel Size, Circumference and Speed), plus get a great setup with 14.6

A 27.5" wheel with a 2.8 tire is 2279mm circumference. Besst Tool and .23 app allows either 2280 or 2278mm

[Beards]

joegold100 it may be time to get 29inch tires :). Seriously though, how frustrating. Have you called or contacted x1’s CS to inquire about how to adjust any of the setting in controller/computer?

[KTMracer63]

Besst Tool and App....problem solved

[K442]

Speed parameters seem to be all over the place on this thing. Yes, the speedo has been reported to be pretty inaccurate. I think the 'tire size' parameter is locked in at 28" - but that is still an approximation for a 27.5x2.7 tire. (My other bike computers have a place to enter measured tire circumference in millimeters which is much more accurate.) The speed cutoff in my controller is set to "90kph" but assist dies right at 40kph/25mph. I also noticed the speedo rollover, though I have mine set in km, so at 65kph, it starts counting back up 1...2...3...4...5, etc. Really a quirky piece of electronics!

[AZguy]

I've never expected these "factory" speedometers to be accurate at all for so many reasons

Different tire and even tire wear/pressure will throw them off, they need to be calibrated minimally for different tires and most only accept 1" diameter increments so lucky to get within a few percent

FWIW moto speedometers from the factory are always optimistic by 5-10% - most right about 7%... it's well known and clearly deliberate

If you want accurate speed you need a speedometer you can calibrate or better yet get a wheel speed sensor like what garmin has that gets calibrated automatically in the receiving GPS unit

I've got a batt-man that you can hook up a PC to and set the wheel circumference and it's pretty good but it's a pain to get it right on in the first place unless you have the aforementioned GPS with wheel sensor and then it changes a very little bit with wear and pressure and every different tire I've had throws it off... I got it close once and it's plenty close enough with all the other nonsense I don't bother with it anymore

Later on I got the garmin wheel speed sensor and it's spot on, self calibrates so all the other issues go away. I can use what it comes up with for circumference to fine tune the batt-man but why bother? because in the end I don't really care about having a speedometer to begin with... the only reason I got the garmin wheel speed sensor is because the GPS I run on the bike was compatible and it was very inexpensive and sold as a package with the pedal cadence sensor for about $50-$60 when I got them so why not? I've got the pedal cadence sensor attached to the ring instead of the pedals, temperature sensor and both are very useful... I've also go the heart rate sensor... of all the sensors the most useful is the pedal cadence although out here that temperature sensor is nice to have too... heart rate is more for entertainment when I look at my logs - my heart rate is highest when I cross busy streets

[EL34]

It's because you cannot set the wheel circumference in the X1 meters like you can with most bike speedo's

I always did roll outs on my garage floor to get the wheel circumference
This was done with me on the bike and the tire pressures set.

My X1 is off by about 2 miles per 30+ miles

[AZguy]

2mi per 30mi is >6.5%

[KTMracer63]

It's because you cannot set the wheel circumference in the X1 meters like you can with most bike speedo's

I always did roll outs on my garage floor to get the wheel circumference
This was done with me on the bike and the tire pressures set.

My X1 is off by about 2 miles per 30+ miles

Have you actually connected the Besst Tool, running app 1.2.23 and adjusted the circumference values ?

[EL34]

Have you actually connected the Besst Tool, running app 1.2.23 and adjusted the circumference values ?

No, I don't "actually" own that tool
I've had no need for it so far

I have another X1 coming in July
I may spring for the tool later.

[KTMracer63]

No, I don't "actually" own that tool
I've had no need for it so far.

maybe you'll be surprised what you can do with it.....
would be pretty cool if Bafang or Luna made the 14.4 firmware available for download, then we'd be able to compare/swap between the 2 (14.4 and 14.6), when using the Besst.

[EL34]

maybe you'll be surprised what you can do with it.....
would be pretty cool if Bafang or Luna made the 14.4 firmware available for download, then we'd be able to compare/swap between the 2 (14.4 and 14.6), when using the Besst.

I'll be able to do that when I get my new X1 since it comes with 14.6 and my old one is 14.4

[KTMracer63]

Keep in mind that the 14.6 coming from Cali might be set up with parameters that are off a little, depending who does it and with what Besst App version.
Some have mentioned their max speed at 28mph coming from Luna (these are some of the X1 riders in the FB X1 group)......and there's a group of us that have tuned the controller (with 1.2.23 app vs. 1.2.18) to 37.5mph/60kmh with 27.5" wheel with 2280 or 2278mm circumference.

Granted, I don't need to use the Besst tool any longer (very happy with 14.6) however, I'm glad to have bought it for future firmware releases/swaps and I can always plug it into the controller and get the true controller read (battery voltage included) when the battery reduces to specific percentage levels according to the "original" display read (don't have the 860). It's the 1.2.23 app that's the key component for realistic adjustments ("writing" the parameters).

Will be cool to see your butt dyno thoughts/perspective when you run the 14.4 comparison to the 14.6.....

[Icon6]

KTMracer63: How do you get the max speed to go to 37.5. Mine cuts off at 27.8 and when I try to change the speed setting, it won't allow me to toggle above the assist levels. Also, the battery voltage is set to 52v and that can't be changed either. Do you know what the boost level does? Lastly, can the software version be determined by these display shots? My X1 was shipped on April 2nd if that helps. Thanks.

[KTMracer63]

KTMracer63: How do you get the max speed to go to 37.5. Mine cuts off at 27.8 and when I try to change the speed setting, it won't allow me to toggle above the assist levels. Also, the battery voltage is set to 52v and that can't be changed either. Do you know what the boost level does? Lastly, can the software version be determined by these display shots? My X1 was shipped on April 2nd if that helps. Thanks.

1. You would need to buy the Besst Tool and download the Best App....1.2.23 (see link posted by Sebz) https://electricbike.com/forum/forum...2-bafang-besst
Adjust the Speed, Wheel Size and Circumference settings to the Controller via the Besst App (running on your computer) while the Besst Tool is connected to your motor/controller and Laptop (USB port).

2. From hands-on experience, the 1.2.23 version is the better of the 2 apps provided by Luna. 1.2.18 is pretty much useless.....just like 14.5 firmware.

3. I haven't messed with Boost feature yet, so don't have any input there......try it, see what it does.

My bike is a Ludi mod using Original Display, 14.6 firmware, with 37.5mph / 27.5" wheel and 2280 or 2278mm circumference (for 2.8" tire). I use both 5 and 9 level PAS and with 38t sprocket have pedaled up to 33/34mph flat surface (highest PAS level and throttle).

[Icon6]

Thanks for the info!