Monday, June 26, 2023

GPS Take 3: Wahoo Elemnt ROAM - Part 3

 Last time I left you off here concerning the Elemnt ROAM, I had reported that it was a 'waaaay better experience" than my previous GPS tries, and I still stand by that. 

That said: I got the climb screen to freeze up again.

I swiftly swapped over to the normal data page and it went right back to working again, and it never did that again. You might think I needed to do an update. Well, thanks to one of you readers, I did that before the climb page freeze. So, clearly there is an issue there. 

But overall, things are going well. I have had another unique experience that I wanted to pass along here, plus a surprise finding. Maybe it won't surprise any of you, but for me, it was a big surprise and it caused a bit of a data skew that, in my opinion, was funny. 

First, the surprise. I swapped over the mount to my Twin Six Standard Rando v2 bike so I could use the unit with it. I didn't think about how I had two sensors on the bike from the Sigma GPS computer I tried. I had forgotten about them. One was a speed sensor and the other was a cadence sensor. I believe the cadence sensor magnet is dead, as I recall seeing a low battery indication on that the last time I used the Sigma, but at this point of the story, I wasn't cognizant of that fact. I was not remembering the sensors at all.

Check out that maximum speed, baby! Oh yeah!

As I fired up the computer, and waited for the unit to obtain the GPS, it detected the speed sensor and paired with it. Now, I did not know that until the unit beeped and told me a sensor was paired. That's when I remembered: "Oh! Yeah! I have a speed sensor on here that is working!". 

As I rolled off, I may have done something wrong and not paired the sensor correctly or I moved when I wasn't supposed to, but I did something because 83mph! 

What the....??!!!

Then as I rode that speed walked down until after a couple blocks it settled into a believable readout. However; that set the maximum speed and well, the average was screwed up too! Ha! No big deal, but maybe someone can explain what I did , or did not do, there because I have no idea. Oh! And this sensor got those little lights to work on the unit that tell you how far below or above average speed you are going. That was nice too. Apparently you cannot have that without a sensor? (Throw in comment concerning poor instructions here.)

This was also the same ride I got the unit to freeze up on the climb page. Also, I had the unit not tracking me correctly after I made a right hand turn out in the country. This was on the climb page and it was when I was following the "VAM" (Vertical Ascent/Meters). The road was climbing and flattened out right before the corner, the right hand turn went to an ascending portion of the road and after about 50 yards it descended for approximately a 1/4 mile run. 

The turn was made and the climb data showed me waaaaay back on the grade instead of near the top. Then I descended. The VAM went negative as the GPS was still tracking me as traversing the road which was ascending, or in other words, the GPS was showing me traveling underground! Cool! Now I'm a gravel mole!

That was pretty laughable so I switched off that page for the remainder of the ride. That wasn't all the weirdness I discovered either. Nope. My desk was traveling at 9+ mph at one point last week as well. Check it out....

This popped up as I was trying to see if I could edit a page.

Yeah....I have no idea. All I know is that GPS is weird. Weird and maybe not quite ready for prime time, at least not for me, at any rate. Again- best GPS experience for me so far by a mile, but still not without its quirks and mysteries. And is it really accurate then? I don't know, but if I had to bet, I'd say probably not.

And I still cannot get elevation read out in a running fashion as I could with the old Lezyne.  

So, as of now I still have not done a turn-by-turn test, but that will happen once I have a three hour window or more to use for a ride. So, we'll hold off on a final verdict until that time happens. If it comes through as a reliable guide for riding, then it will be useful. If not? 

Well, I will have tried.


Phillip Cowan said...

The above/below average speed lights will work with GPS alone. It's probably more accurate with a speed sensor though. If you use a heart rate monitor it's one or the other because both features use the side LED lights.

Guitar Ted said...

@Phillip Cowan - That's interesting because the side lights did not work until I put the unit on the bike with the wheel sensor. I'll have to see about that when I use it on another bike here.

hank said...

G-Ted, Howdy;

GPS is a fun thing to study. Hopefully, the unit is using WGS 84 as it's Datum.
It is becoming the Standard. Here's a Wiki link;,recreational%20and%20commercial%20GPS%20units.
Have some fun.


Guitar Ted said...

@hank- Ouch....That makes my head hurt reading it. I sort of understand the overall concepts, but it would seem that while the framework is there for a GPS unit to work from, it might be more that the actual program trying to utilize the framework is what the problem is here.

My limited understanding of GPS comes from some experiences I have had and from others who I knew that used more sophisticated devices and GPS data than I have ever had the pleasure of using.

For instance, back in the late 2000's I was sent a GPS elevation profile in 3D that showed an entire Trans Iowa course to a depth of 10 feet underground! I was told that government GPS data was from a sampling rate much more intense than consumer data was drawn from so that accuracy for government was higher. The 3D map I was forwarded was, not unsurprisingly, from a government source. (Which I was probably not supposed to see!)

Fear rothar said...

Regarding accuracy, consumer GPS has shared similar accuracy to military GPS since 2000. See Selective Availability and Is military GPS more accurate than civilian GPS?

Nooge said...

The climb features are new and it looks like they still have a few bugs to work out. They typically release new software about once a month, so they hopefully will get it sorted out soon.

For the speed sensor, I believe that is the auto calibrate feature that you experienced. Instead of making you do a roll down test to get your wheel circumference, it just reads GPS distance/speed for a while and divides out the number of wheel rotations reported by the speed sensor (which is actually just a RPM sensor). I’m guessing the first time it tried to calculate the circumference it pulled a bad GPS reading. Then after more samples the bad data got averaged out.

Again, GPS inaccuracy from smoke or being indoors or anything that interferes with the signal, will give bad input to the software. There’s not much they can do about that.

This wildfire smoke is getting really old. I’m not used to that in Michigan, but it’s bad enough that I’m getting weak FM signals on stations that are normally strong. And that’s with an AQI of 100. We might hit 300 later today :(

Guitar Ted said...

@Fear rothar - I read some of the article and found this to be relevant to my past experiences from that article...

"High-end users boost GPS accuracy with dual-frequency receivers and/or augmentation systems. These can enable real-time positioning within a few centimeters, and long-term measurements at the millimeter level."

This was what my friend in the government was telling me back in the mid-2000's. That consumers didn't have those "augmentation systems" and that the government did. So consumer accuracy suffered compared to what the government had available.

And do we know what the government has now? ;>)

There's always that.

Guitar Ted said...

@Nooge - You say, "The climb features are new and it looks like they still have a few bugs to work out." So, it is fair to say that this unit is "not ready for prime time". See, this is the kind of thing some people might be willing to put up with- That being R&D in the consumer field with "bug fixes" as needed. What I am saying is that maybe we need to "fix" everything before we release it into the wild. But today's consumers don't seem to mind the inconveniences and frustrations incurred by software that hasn't been fully worked out before it is made for consumers to try out.

Wildfire smoke was not an issue on the day I experienced the faults, but I agree that it could be a contributing factor to my first outing with the Wahoo.

I also agree that this is wearing me and you down. The smoke is very bad today here and I have a pretty good headache from it. This is looking like a Summer of Suck" at this point.