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ROLLING PAST A POINT

This has happened to all of us. You are laying out a course, and something breaks your concentration, and you ride past the point where you were supposed to stop and mark a split. What do you do?

If you have a Jones counter, you simply roll the bike backwards until the proper reading appears.

If you are using an electronic rig with a marked rim, it’s somewhat more complicated. Example: The proper split is located at a reading of 749.63 revolutions. I overshoot, and when I recover I see I am at a reading of 752.27 revolutions. How do I get back to where I want to be? It’s more complicated than simply rolling backwards. It involves a calculation and some more time-consuming bike gymnastics.

Moreover, if I have done this how do I report it to the certifier? Most will probably ignore it and present the data as though no overshoot occurred, in spite of the chance that a mistake occurred. They will sanitize the data, and leave no trace that an adjustment occurred.

I have overshot, and compensated. It’s an easier process with a counter that rolls backwards, and less prone to error.

Commentary is invited. If you have used an electronic counter, what do you do when you roll past the desired stopping point?
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Thanks to this discussion board I just finished my first course measurement With a couple little tweaks to my maps and some course point descriptions it looks like our slightly changed 5 and 10 k races will be certified. Since I used a Protege 9 compute with a rim marked in .025 revolutions I had to be aware of this potential problem.

First, to take precautions I had the splits to mark written down right in front of me on a notebook attached to a clipboard on the handle bars. (A great idea I picked up from this group somewhere!) With the computer display right next to it, it was very easy to see and prepare for the critical revolutions. I imagine I would have had potentially more trouble with a counter mounted on my hub with the notebook and handlebars and cables in the way.

But this question is not about precautions, its about the inevitable eventual snafu.

I had a problem with one of my rides where I was marking miles but missed the faded paint for the old turnaround. This was kind of like riding past a point. Even worse since I had to meander around to find the old mark. I wasn't too put out since I figured as a first timer I'd have to do multiple rides to make sure I had the process down, and this course was only a 5k.

In this case what I did to salvage my ride somewhat was find the old TA mark and head back to my last mile and reset my computer to zero. I just adjusted my readings, now reading mile one revolutions to find mile two.

How did I explain this to my certifier? I didn't. The paperwork says to check your work and if the rides are not close enough, do it again. Does the certifier need to know every problem we had if the problems were corrected for and the corrections were within the allowed margin for error? Would a mechanical counter roll back need to be reported to a certifier? In my case it was a simple addition of "mile one" revolutions to my "new" ending reading to get a total to compare to a second ride. The rides were within .05%, so I was good, but I still rode the course again to get a double check on the mile splits (I just cruised over them while riding and glanced at the cycle computer right in front of me) and to verify the course length. Was this sanitizing the data? If the ride would have been off by .08% I'd have had to re-ride. (I still did because I wanted to be extra sure). The abiltity to rezero my counts made the process easier.

So I guess my solution adds a little more riding, maybe even a total re-ride. If the split was not going to be certified, why not just ride on and make sure of the next one? The missed split could be recorded on the next ride or picked up from either bookend mile mark afterwards. If the mark was to be certified, though, I'd only be comfortable with a start-over, or a verifying ride at least.

Regardless, the extra work would mean measurers probably would repeat that mistake rarely, and I think watching that cycle computer roll off the revolutions right under the nose makes this problem easier to avoid in the first place.

I have little experience to speak with any authority, but I'd thought I'd share my recent experience and say "Thanks" to all you guys for your informative thoughts and precautions here.
I have seen Chris's paper work and he is to be congratulated on a fine job. I agree with his reasoning about missing a split. You should just continue on with your ride and mark the split later.

As for looking at the EC counter on the handlebar or the JR counter on the fork, they both are easy to read. The old Jones counter may have been a problem, but the new JR is the best.

I suggest that any measurer should be familiar with both types of meters.
Pete:
I have documented answers to your questions many times over the last five years; nevertheless, I will review the topic of overshoot yet again, because I can describe fresh approaches.

The Jones correction for overshoot by backing up, although expressly forbidden in the RRTC Operating Manual, works well for a couple of revolutions. It then becomes increasingly inaccurate, dangerous, and impractical. The measurer must turn the bike and ride back; and this entails more meter readings and calculations. The table of splits must be recalculated.
The correction with electronic meters is less likely to be needed than with the Jones because of the clarity of readings while riding. It is just as easy as that for the Jones where only a small number of rev are involved, but is much superior for a large number:

1. Correction for an overshoot of about 5 rev.
Roll the wheel back though the zero point by a number of times equal to the excess rev and set the rim value.

(Pete, if I encountered your above situation, I would roll back the wheel three times through zero to a rim reading of 0.63.)

2. Correction for an overshoot of more than about 5 rev.
Stop the wheel at an easy-to-calculate and remember excess rev and the desired rim value. Mark the road at this position, turn the bike around, zero the meter as usual, and ride back the excess rev.

3. Resuming measurement after a correction or taking the wrong route.
In the above corrections the original meter reading is lost when correcting for more than 0 whole rev. This is usually not important because the meter will usually be rezeroed after the correction, but when necessary the original meter reading can be saved.
It is essential to do this when using a similar correction to compensate for taking the wrong route. Select a rim reading, say 0.50 and turn the bicycle around at this point. Deactivate the meter by moving it back on its mount. Zero a second meter as usual and ride back until comfortably on course again with an easy-to-remember whole number of rev. Turn the bicycle, rezero, and ride this number of rev along the correct course. Stop, and at his point on the road set the rim to 0.50. Activate the original meter by pushing it forward on its mount.
Instead of a second meter, the second wheel on the Protégé 8 or 9 can be used.

4. Add/subtract meters.
No calculation is necessary and meter reading from the original start is not lost with the add/subtract type of meter such as the Veeder-Root A103-001.
In overshoot correction, the desired rim reading is selected, the bicycle turned around on this reading, decrement mode selected, and the bicycle ridden back until the desired reading is shown on the meter.
Similarly, to get back on course, a rim reading of say 0.50 is selected, the bicycle turned, decrement mode selected and the bicycle ridden back until comfortably on course again. The bicycle is stopped on 0.50, turned, increment mode selected, and measurements resumed.
Last edited by neville

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