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Yesterday in downtown Detroit I was not able to use my usual calibration course because there was an event going on at its location. So I had to use another cal course that I measured in 2017 that I haven't used in a very long time.

The endpoints of this course were both at the edges of sewer drains, but when I got to the course I could see that there was brand new concrete around the drains, and I became concerned that the drains themselves had been moved. So I pulled out my measuring wheel and walked the course with it. Sure enough, the measuring wheel said 260+ meters, and the course certificate said just a little under 258 meters.

So next I pulled out my steel tape and nails and spent the next 40min or so taping the course. My steel tape measurement came out 45mm longer than the course distance on the certificate. My measuring wheel had a 0.7% error for a straight-line measurement!!

Moral of the story: Next time somebody tells you they "wheeled" a course, take it with a boulder-size grain of salt.

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My question is why was this calibration course ever approved in the first place because it is under 300 meters? I am under the impression that calibration course must be at least 300 meters or am I wrong about this. According to the manual it says 300 meters. If there is a new manual that says different could you please give me the web site so I can stay up to date on the course measurement and certification procedures. Thanks.

Not a problem. I just thought maybe they changed something and I didn't know about it. I am slowly getting out of measuring courses. Mainly because I am getting older and am retired. Races seem to me not to want to spend the money to have races certified these days. Plus I don't care for the online way to enter courses. I always seem like there is a problem when I do. Topics for another post someday.

I was an original champion for the online registration system. Jim Gilmer sank a major portion of his life into creating this system and making it work. He and his team of developers spent a huge amount of time and expertise to get our system up and running - for just a pittance. Several volunteer RRTC leaders generously assisted. Jim had well-defined plans for continuing development and improvements. However, it seems that USATF has declined to fund this project. For what reasons, no one seems to know.

So, we have USATF asking us for money for "memberships" that have little or no value to us, we have USATF CEO Max Siegel personally raking in millions of dollars every year, we see top USATF executives making large 6-figure salaries, while our online certification system is now badly in need of maintenance and updates, yet USATF expects RRTC to do everything as volunteers. Or is it as "serfs"?

Last edited by Race Resources LLC

I concur with Mark's observation about the inaccuracies of measuring wheels. I learned that many years ago when I thought that I could easily make course adjustments with a measuring wheel rather than using a steel tape which is more cumbersome. In a similar manner to Mark, I checked my wheel for accuracy on a calibration course. I found it to be about 5 feet off over the 1000' cal course. There's also obviously inaccuracies in walking with a wheel. Wheels are great though for rough measurements and easier than going through bike calibration.

I think measuring wheels are much more susceptible to inaccuracy due to surface differences. The cal course I measured with my wheel was fairly rough asphalt. My wheel as plastic with a rubber strip around the circumference which is fairly sticky, but the wheel as a whole is pretty rigid. I don't think it handles the roughness of the asphalt well.

A few years ago I experimented with a couple wheels on a golf course. I measured out very short cal courses with a steel tape on two grass surfaces. One was regular looking grass, and the other was the grass on a fairway, which was very short and kind of spongy. The calibrations on each surface were very different, and they were also differences depending on how much I pushed down on the wheel as I rolled it. It did not inspire much confidence in measuring wheel measurements of cross country courses.

Also, many years ago I measured a track with a wheel. I first used my steel tape to measure from the 100-meter start line to the finish. It was spot on. Then I used that to calibrate the wheel. It gave measurements that were slightly different than 100 meters. I then measured the track following the line of the inside lane. Finally, I adjusted my measurement to account for the fact that tracks are designed to be 400 meters along a line 30cm (or 40cm if there is a curb) out from the inside line. The final measurement was just a few centimeters off. I actually think this is the best way to measure a track because it's easy to follow the inside line with a wheel. That would be very difficult on a bike. If the track is just part of a 5k then the riding error isn't going to matter much. But if the measurement is of just the track, the inevitable bike wobbling is going to make a big difference.

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