Sunday, August 24, 2008

Ride Report: ORR Nehalum 400k

A view of Tillamook Bay near Bay City south of Garibaldi

This report talks about the 400k route as well as some product reviews or comments on things that worked and things that didn't. Since my endorphin level is near maximum today, it must have been a pretty good ride. The Tour de Couche is on today so this will be a short post as I don't want to miss anything on the History Channel or Comedy Central.

The route provided a quick glimpse of the beauty of Oregon. It also provided 11,000 feet of climbing and several notable and challenging hills. I used to think that if I mentally distributed the estimated elevation gain long the length of the route, that it would indicate the relative difficulty of the route. After this ride, not so much.

Micheal did a great job with the route. It was challenging and scenic adding some new roads and some that we havn't seen for quite a while. All of the controls except the first and last were information controls. The route sheet was well done and the distances were almost exactly the same as my gps until Carlton just 18 miles from the end. The route went counter clock wise which worked good for summer temperatures. I was near the coast by the time the heat started to build so the temperatues were perfect. Ken established a refueling stop midway up the Nestucca River climb with food and water.

There were a few rough spots on the route. Highway US-26, and especially the part that we rode has too much traffic, moving too fast, a hill that some might call too steep and a significant length of road with little or no shoulder. The area around Tillamook on US-101 was also pretty busy. The only other problem was some construction/repair activity and the primitive and deteriorating road condition on the Nestucca River Road.

I forgot to bring my bike computer so I threw my Garmin hcx etrex into my handle bar bag in case of emergency. So that is why this post has so much elevation profile ranting. Randonneurs love to calculate things and a gps stores huge volumes of real data, ripe for calculation.

Bikely Elevation Estimates

Bikely elevation estimates are sometimes not very accurate. For example, the Bikely calculated elevation gain for the Rocky Mountain 1200 was 16,200 feet while the BC Randonnuers show the elevation gain is over 27,000 feet. The elevation estimates appear to get less accurate as the length for the route increases. The first profile below shows a Bikely profile for the Nehalem 400. The bikely route was entered manually using the web interface. The second graph shows the elevation profile and the cumulative elevation gain using Excel to plot the values using the raw Garmin GPS data containing 7,776 data points.

When Garmin saves a route on the hcx etrex gps, it averages the point data and produces a data file with a maximum of 500 points. Each data point has a series of attributes like the time, elevation, line segment length, speed, elapsed time to traverse the segment, bearing and GIS position (example: latitude and longitude). When the Garmin saved my Nehalum 400k route, the total number of points was reduced from 7,776 to 500. The average segment length went from 169 feet to 2,583 feet. The problem comes when averaging elevations. It is possible to go up and down a few times in 2,583 feet and averaging the elevation data is going to result in the loss of data accuracy.

The raw gps data results in a cumulative elevation gain of 13,400 feet while the summarized data shows only 9,200 feet. Why did the Garmin gps show me 11,000 feet of elevation gain at the end of the ride while the saved and summarized route shows only 9,200 feet of elevation gain? Why is the calculated cummulative elevation gain from the raw Garmin data greater than either the saved track or the gps display at the end of the ride?

It might be a coincidence that the Bikely elevation estimate for the route that I manually entered into Bikely is almost exactly the same as the summarized Garmin data. For most applications, the cumulative elevation gain is proably not an important concern. Who would care other than bikers, runners or hikers? I'll spend some time on the Bikely Forum investigating the elevation estimate issue.

Route profile calculated after manually entering the route into Bikely.


Route profile calculated from raw GPS data using ExcelCalculate Route Profile (from Excel)

Nehalum 400k Route


View Larger Map

Assos FI Mille Cycling Shorts

I purchased several pair of the Assos FI Mille shorts before the Rocky Mountain 1200 because of the rave reviews that I heard from experienced and respected SIR riders. I gave them a try on TourBC prior to the Rocky Mountain 1200 remembering a little problem I had several years ago on the Last Chance Randonnee.

I've given them a fair chance but I'll have to leave them for shorter rides. The Campionissimo insert made from 5 different textiles, Anatomically formed and Featuring Elastic Interface technology wants to crawl up my butt. The shorts appear to have a lot of Campionissimo material between the legs where the legs and saddle collide. I've found that I end up riding on a bunched up pile of Campionissimo which causes a contusion in a most inappropriate place. Damn you Campionissimo!

Schmidt E3 LED light

I've only used my E3 a couple of times but I'm just about ready to go back to my twin E6 headlights. Perhaps I have a grudge against the E3 having the unfortunate experience of having a rider with an E3 follow me at night. It is not a good experience. My E3 is mounted on the skewer and part of the beam shines through my front wheel producing a dark void left of center on the road ahead of me. The beam is not focused like the Schmidt E6. With the E3 I can see a large area but not very well. With the E6 I can see what I need to see and I can aim the lights to compensate for various conditions.

The skewer mount puts the light just past the point of good judgement. When the lights are mounted within reach, you can turn them on and off and point them up and down to allow for various conditions. For example when your going down hill fast, you want to aim them farther out to see farther ahead. When your following someone you might aim them down so they don't glare into mirrors or mess with the riders vision.

I like the simplicity of the E3 and skewer mount. It is easy for me to change the wheel to a different bike and quickly have a headlight for night riding. I think it will also be easier to travel with when it is time to reassemble the bike into a hard shell bike box. Maybe I'll come to like the E3 in time but my twin E6 headlights are calling me back.