Copyright Velocomp LLP 2005-2015
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-5 mph to -7mph (the cyclists ahead of you are pushing the wind down the road,
creating a net tail wind for you. That’s what drafting is all about!)
UNDER WHAT CONDITIONS CAN THE NEWTON BE “LESS ACCURATE”?
There are two extreme riding situations where it is difficult for the Newton to measure
watts with highest accuracy:
1) Sharp turns such as hair-pin turns. During sharp turns, where your handlebars
are pointed into the turn, your watts may read low. As soon as the turn ends your watt
readings will return to full accuracy.
2) Pedaling at high speed in a tuck. While pedaling on downhills, any minor
variation in ride position from your normal ride position (such as going into a tuck to pick
up more speed), or any error in your drag coefficient measurement, can cause a false watts
reading. The reason is simple: wind resistance varies as the cube of your speed, so high
speeds “amplify” enormously the watts errors caused by ride position changes. As a
practical matter, most riders DON’T pedal on downhills (it’s a very poor use of rider energy)
and when not pedaling, any Newton with a cadence sensor will report zero watts.
WHAT CAN I DO TO GET THE MOST ACCURATE RESULTS FROM MY NEWTON?
Before obsessing too much about accuracy we recommend you learn more about Accuracy
and Consistency, see Appendix 4, pages 51-53. Your Newton will provide highly consistent
results, right out of the box, but you can fine tune its accuracy using ISAAC, and by
performing a Cal Ride.
HOW DOES THE NEWTON MEASURE TEMPERATURE?
The Newton measures the temperature at the wind port. If you’ve been riding and air is
moving around your Newton, the temperature displayed will be close to the outdoor
temperature. However, if your Newton has been sitting in the hot sun, without airflow over
it, the display could show a significantly higher temperature.
NOTE
: IF YOU OWN A BLACK NEWTON, IT WILL TEND TO OVER-REPORT TEMPERATURE BY
ABOUT 10F-15F, PARTICULARLY IN SUNNY WEATHER.
I PURCHASED AN UPGRADE KEY FOR MY NEWTON. WHAT HAPPENS NEXT?
You will receive an email asking you to send us the serial number of your Newton. After we
receive your serial number we will email your firmware key to load into your Newton with
ISAAC software. Connect your Newton to your computer and use the ISAAC command
“Device/Upload Feature…” to permanently install the key into your Newton.
HOW DO I FIND OUT WHAT OPTIONAL FEATURES ARE IN MY NEWTON?
Connect your Newton to your computer and launch ISAAC. Go to “Device/Unlock
Feature…”. Then click the “Get Unlock Status” button. All of the optional features installed
in your Newton will be listed.
WHAT IS “TOTAL VERTICAL CLIMBED”?
Any time you climb, the Newton will accumulate the amount of elevation gain.
Example: You climb a 100 foot hill, then descend 50 feet downhill, then slowly climb
another 25 feet, and then ride back to your starting spot, descending 75 feet along
the way. The Newton will show your Total Vertical as 100 + 25 = 125 feet.
