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WHAT DOES "HEADWIND" MEAN?
The headwind speed that is displayed by your Newton+ is the TOTAL magnitude of wind
blowing directly in your face as you pedal. A few examples make this easy to understand:
You ride at 15mph directly into a 12 mph headwind. The Newton+ will read 27 mph
•
headwind.
You're going 18 mph and there is a cross wind of 10 mph. The Newton+ will display
•
18 mph as the headwind (remember, you're riding perpendicular to the wind's
direction.)
You're going 20mph and there is a tailwind of 10mph. Your Newton+ reads
•
10mph as the headwind (it knows you're getting a bit of a free ride from
mother nature!)
NOTE: WITH "ABS WIND/YES" YOUR NEWTON+ WILL REPORT THE ACTUAL WIND SPEED.
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) When 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 mount will report zero watts.
WHAT CAN I DO TO GET THE MOST ACCURATE RESULTS FROM MY NEWTON+?
Your Newton+ will work extremely well when it is properly calibrated:
1) Perform the Fast Start sequence AND the Cal Ride. For the highest level of
accuracy, you may also perform multiple Coast Downs after completing the Cal
Ride. Make sure to use the Newton+ software to analyze your Cal Ride/Coast Down
data.
2) If you don't pedal on down hills, the cadence sensor will force watts to zero
whenever zero cadence is detected.
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.
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Copyright Velocomp LLP 2005-2013
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