Garmin GPS vs Wheel Sensor! How much distance are you missing?

I was wondering just how much mileage I’m losing using a conventional cycling GPS vs a wheel sensor. Find out and comment any questions or ideas below!

[shrinkingshrimp]

Short and no bs video, and the only one I found in this subject. Thank you.

[JCBike]

On a mtn bike trail, GPS based mileage is off
Every
Single
Time ..
We’ve tested over and over and your 10% loss is accurate. Our 10.75 mile trail was marked off by a manually pushed walk behind wheel that measured in feet and inches, so we know EXACTLY how long our trail is and our mile markers are accurate. Every GPS computer registers between 8.8 and 9.5 miles. The most accurate is definitely with a wheel sensors on a properly calibrated tire circumference just as you described. I wouldn’t even trust GPS on a road ride either, unless going in a straight line from point a to point b.

[RainerSh]

Thanks. That was a good comparison. Specially for me as roady was thinking how much sense a speed sensor might make.

[richardbarnes]

Exactly what I found on a MTB ride today through short decents and pinch climbs under heavy foliage. Expected 23.5km based on previous efforts. Today I clocked 26.6 using a new set-up including a calibrated wheel speed sensor.

[Abhyyt]

thaks for the effort and letting all of us know more 🙏

[philoso]

Nice video and presentation.

I agree with your findings in video. Same what was used by the Romans, called odometer.

Consistency? I set up my device on lap count by distance for three to five laps runs. It was within one count or one bike length over a lap of five miles lap by laps on city curb side path. Not even accounting on the normal tire-road skid or drag.

One thing I wanted but failed is to characterize a one revolution reference distance value with tires loaded by my body weight.

GPS is inaccurate in jungles, either concrete or woods also influenced by dust rain and humidity.

[GorgeGeorg]

Does your GPS account for (any or all) elevation changes? If you're 'mountain' biking your always going up and down trails. Your travel distance will differ from your horizontal distance by the cosine of the angle of incline. So if you're averaging a 10% incline (up and down) over your trip, the GPS and wheel distance will differ by 1.52%

[nyanuar]

That house looks like my dream place to life

[Jcool]

I calculate the wheel size. I sit on my bike and measure the radius of the wheel. Then the wheel size is: 2*pi*rad.