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Monthly Archives: April 2013

Sources of error in becoming a Stravasshole

I ashamedly use Strava. Yes it has been motivating me to ride harder, but still not to become a jerk passing people. For the last five years I have been barely pushing the pedals, going for the inverse of Greg Lemond’s famous quotes, I was making it easier, so I was getting slower.

One thing to remember about Strava results, some smart phones (iPhones especially) are a little loose on how they calculate location. Often smart phones calculate their location by using signals from cell phone towers and not the GPS satellites. This reduces the load on the processor, and thereby extend battery life, and allows a much quicker initial location calculation.  

For all you know, the local KOM’s iPhone could have calculated him as crossing a segment’s starting line 20 feet after he really did. May not sounds like a lot, but so many segments are so short it could end up make the difference.

I ran both my iPhone 4 and Garmin Oregon 300 at the same time this weekend at Fountainhead. Made a 13 second difference on a segment for me. On the third loop, the iPhone showed my time as 24:57 (88th/446), the GPS 25:43 (106th/446).

http://app.strava.com/activities/48630606#852924689
and
http://app.strava.com/activities/48751273#856182055

I also made this visual comparison of tracks up near Patapsco. 

Garmin versus iPhone_750

from this ride:

[url]http://app.strava.com/activities/46661982[/url]
and
[url]http://app.strava.com/activities/46677184[/url]

 
 

Trail Work at Fort DuPont Sat April 6th

I am leading my first trail work at Fort DuPont on Sat April 6th starting at 9:30 am. Originally I proposed this Sunday, forgetting it was Easter.  
We will meet at 9:30 in the main parking lot along Fort David Drive just north of Randal Circle. (See map below). We will have gloves and bags for you, but if you prefer to bring your own that is cool.
We’ll break into groups to cover multiple sections. The highest priority is the section between Fort Davis/Texas and Massachusetts.  Not much trash, but the most used.  The next section is between Fort Davis/Texas and North Capital with a lot of trash. If enough folks  come, we’ll also spread out to the southern sections beyond Branch Ave. The attach basic trail map shows what sections we’ll be working on.
Call me at 814-777-2580 if you have any questions, arrive late and want to join us, etc.

Fort DuPont ride meet-up location

Fort DuPont ride meet-up location

 
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Posted by on April 2, 2013 in Bike, DC, Fort Dupont