Descent: 80 feet (24 m)
Description:
The west side of Golden Oak Drive climbs up from Alpine Road (about a
half mile above Arastradero) to Peak Lane (which connects with
Cervantes Road). After Peak Lane, Golden Oak goes back down
the hill to Alpine (see Golden Oak (east)). Peak Lane, after a brief
30-foot rise, connects with Cervantes, which can be descended (with
Westridge) west to Portola Valley Road.
Altimeter altitude
(Altitude linearly interpolated from altimeter
samples, and smoothed with a 0.04mi gaussian.)
Each horizontal line is 100 feet. Each vertical
line is 0.2 miles. Gradiometer grade
(Grade linearly interpolated from gradiometer
samples, and smoothed with a 0.04mi gaussian.)
Each horizontal line is 2% grade. Each vertical
line is 0.2 miles. Altimeter grade
(Grade linearly interpolated from altimeter
samples, and smoothed with a 0.20mi gaussian.)
Each horizontal line is 2% grade. Each vertical
line is 0.2 miles. Comparison of grades
(Green grade is from the gradiometer, magenta grade
is from the altimeter, and white is where they
overlap.)
Each horizontal line is 2% grade. Each vertical
line is 0.2 miles.
Overall (averaging my first 20 hills),
the gradiometer grade averages 0.63 (% grade)
higher than the altimeter grade, with a standard
deviation of 4.5 (% grade per road).
This error may be due to:
-
Uneven sampling -- I take more samples when the
hill gets steep.
-
Calibration error (of the gradiometer or
altimeter).
In the end, though, I think that each individual
sample is accurate to within about 2% for that
instantaneous segment of road. My results may
not always agree with my altimeter, but they are
generally repeatable within 1%. I think that
I just need to take more samples to generate
more accurate graphs.
Raw Data:
Dist Grade Alti. Location
---- ----- ------ --------
0.00 10% 490 start - Alpine Road
0.01 9% 490
0.02 13% 500
0.05 12% 520 Bear Gulch Drive
0.08 14% 530
0.12 13% 560
0.15 13% 580
0.17 14% 590 Sausal Drive
0.19 15% 600
0.22 15% 620
0.26 15% 640
0.28 14% 660 right bend
0.31 7% 680
0.32 0% 680
0.33 -9% 670
0.34 0% 670
0.37 9% 680
0.39 12% 690
0.40 7% 690
0.41 3% 700
0.44 10% 700
0.46 14% 710
0.47 15% 720
0.50 11% 740 180 Golden Oak
0.52 8% 760 Holden Court
0.54 0% 760
0.56 -5% 760
0.57 0% 750
0.59 8% 750
0.62 5% 770 230 Golden Oak
0.64 8% 780
0.67 5% 790
0.68 0% 790
0.71 -9% 780
0.73 0% 770 Granada Court
0.75 13% 780
0.77 11% 790
0.79 0% 800 Top - just before Alhambra
0.81 -6% 800
0.84 -8% 790
0.85 -14% 780
0.87 -15% 760 Peak Lane
Back to
Lucas's
cycling gradiometer page.