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Javaman said:
I have a local 5K to measure and get out to Doug Loeffler (I know Doug's business sometimes gets in the way of speedy certification - we've talked on the phone a couple of times.) very soon. Would you like me to send you copies of Protege and JO measurements if I can get my partner to ride the course with me?

It’s not necessary to actually measure a course using a JO and a Protégé. All you need to do is ride around the block several times, stopping here and there and recording revolutions and counts. The JO counter with the metal drive gear records 23.63636363…. counts per revolution of the bike wheel.

Once you have recorded several pairs of readings you should find that each interval will show JO counts to be 23.63636363 times the number of revolutions recorded.

If it’s too cold to ride, bring the bike inside and spin the front wheel by hand. If you have the Protégé set up properly you will find almost perfect agreement.
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Javaman:
Pete is right of course. Mounted on the same bike, results should differ only by your ability to estimate fractions of a count on the Jones. I find that it is a common misconception that that there has to be some degree of difference between results from the two counters.

Some measurers buy Proteges and feel so intimidated that they never get around to trying them. A "period of experimentation" as desribed in the minutes of this year's National Meeting should not be necessary, because I have aready done it. I can send you some quick-start instructions and you should be able to mount the Protege and be up and running within 10 min, if you just number the spokes.
Don't number your spokes. Take the small extra time to mark your wheel in 20 equal parts. You will be doing many measurements - might as well get decimalized from the start. You can waste a lot of time using intervals of 1/32 or 1/36.

In spite of Neville's well-written instructions, I found that a certain amount of experimentation and practice was beneficial. Hands-on can't be beat.
Last edited by peteriegel
I only suggest using spoke numbers in order to get a quick start and agree that decimal markings should be used soon afterwards. There are minor advantages to both types of markings, and I have gone back and forth with both. I now use only decimal markings because this suits my hand-held calculator program best.

I agree that getting quickly to hands-on testing is good, but written instructions should be consulted frequently at the same time. However, by far the quickest way of learning to use the electronic counter is to get a demonstration.

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