The snowstorm today, May 12, has interfered with my internet access so I'll see if this posting will go through.
This past Saturday, two days ago, I did 150 miles in nine hours. That seems pretty good until I mention the 15 mph tailwind I had at the end. I did 50 miles in just under two hours. It was the most fun I've had in years. I spent an hour and a half moving between 30-35 miles per hour just steady cruising. Also the road was following the Madison river and was trending downhill the whole time. I admit the downhill and the tailwind but it was still a blast. The only reason I didn't continue to 200 miles was that my crew was ready to go home.
It was my fault. I miscalculated the distance and gave a destination as the endpoint, not a distance. My calculations were 40 miles short (how did that happen?). So when we reached the announced end they were ready to quit. I have spent a lot of time getting these guys together and they finished the day feeling good. So we stopped.
The part of the day that didn't have the tailwind was doing a loop west from West Yellowstone, over the continental divide twice and back. I did that 65 miles by myself, then met my crew back in West Yellowstone where I repeated the first half of the morning ride, over the passes again. The fastest speed of the day was just before the end, coming into Norris, MT. There is a considerable hill there. As I came down the descent I hit 45 mph, which was when I started touching my brakes. The former tailwind was rather squirrelly in the canyon and I wanted to remain upright.
The West Yellowstone ride was organized by the local Chamber of Commerce and had bikes of all sorts, and me on a recumbent. This was the first time I have actually ridden the same route at the same time as upright bikes and all the predictiions were true. I was moderately slower going uphill and just smoked them all going down. The last rider I past was a real natural athlete. At over 30 mph he could lean to the right, press a nostril and shoot snot well out into the grass. After I passed him I never saw him again but he has set a standard for personal hygiene I will never equal.
This week is the peak week, then start tapering next week. At least the race dreams have stopped for now. Last night I dreamed I was watching home movies with Pete Townsend and the Who. Did he have braces in real life?
Monday, May 12, 2008
Sunday, May 4, 2008
Best laid schemes
I think the snow has stopped. The weather has been atrocious. Have I let it stop me? You Bet! I have another century and various shorter rides done but nothing on the scale I had planned. Am I getting scared? Y ou Bet!
Then this week the house we are renting sold. We have thirty days to move out. Last week end we spent house hunting and this week end was spent house buying. I have to hang around to sign offers for houses, sign counter-counter offers. Sign offers for the second choice. Training for races is right out the window. The bright side?
We have given up. If our last offer is not accepted we move into another rental and stop worrying about it. The good news is that the weather has improved and I have a week off next week. The plan is to do some training centuries, then a double century. Conveniently, from my present house it is exactly 100 miles to a conspicuous landmark in Helena (the Wendy's near the freeway). Food and a bathroom at the turnaround, what more could I want? An early start, lunch at the turn and home by dark...sounds simple. I might go to ski areas to practice long, hellish climbs. I have Bogus Basin in Boise, Idaho in mind.
I'm rotating the bikes through a local bike shop (Bangtail) for tune ups. The Javelin (Thagamizer) is in now, to be followed by the OSS Seiran (Kelson) the USS Seiran (Taranaki).
I have bought the lycra, scheduled the logo manufacture and continue to test the food. The race dreams have started, almost all of them dealing with getting lost. The worst one was the dream of a time station that happened to coincide with a check point for a large cross country cycle tour. There were hundreds of bikes and tables but none of them were mine.
And Tim Woudenberg. He is a competitors nightmare except he's real.
Jolly times. Off to another long ride today.
ChrisM
Then this week the house we are renting sold. We have thirty days to move out. Last week end we spent house hunting and this week end was spent house buying. I have to hang around to sign offers for houses, sign counter-counter offers. Sign offers for the second choice. Training for races is right out the window. The bright side?
We have given up. If our last offer is not accepted we move into another rental and stop worrying about it. The good news is that the weather has improved and I have a week off next week. The plan is to do some training centuries, then a double century. Conveniently, from my present house it is exactly 100 miles to a conspicuous landmark in Helena (the Wendy's near the freeway). Food and a bathroom at the turnaround, what more could I want? An early start, lunch at the turn and home by dark...sounds simple. I might go to ski areas to practice long, hellish climbs. I have Bogus Basin in Boise, Idaho in mind.
I'm rotating the bikes through a local bike shop (Bangtail) for tune ups. The Javelin (Thagamizer) is in now, to be followed by the OSS Seiran (Kelson) the USS Seiran (Taranaki).
I have bought the lycra, scheduled the logo manufacture and continue to test the food. The race dreams have started, almost all of them dealing with getting lost. The worst one was the dream of a time station that happened to coincide with a check point for a large cross country cycle tour. There were hundreds of bikes and tables but none of them were mine.
And Tim Woudenberg. He is a competitors nightmare except he's real.
Jolly times. Off to another long ride today.
ChrisM
Sunday, January 27, 2008
Today I have been playing around with some information from:
www.mayq.com/Best_European_trips/cycling_speed_math.htm
The whole page can be expressed thusly:
WattsRider =Cfriction X velocity X weight + Cair(V + Vwind)^2 X veloc. + Cslope X weight X %slope X V + acceleration
It looks like a lot of stuff but it simplifies into:
Watts necessary to overcome friction = Constant value of friction, which is around .1, X velocity X weight
For me personally, that comes to .1 times 5.8 meters per second, or 13 mph times 77.2 my weight with bike in kilograms
I get 45 watts of power that I need to produce just to overcome the friction of the road and my weight on the hub bearings. The additional friction of chains, idlers, leg hair, cranks etc. is measurable but insignificant overall.
45 Watts for friction plus 70 watts to overcome air resistance at 13 mph = 115 watts to go 13mph flat, no wind
OR: Watts necessary to overcome friction = Constant value of drag times velocity cubed, assuming no wind.
I had to interpret the Cair, the constant value. An upright rider on a Mountain bike is about .9. A road racer in lycra and well tucked in is about .36. For recumbents the only measured value was for a Easy Racer Gold Rush at .046. I'll use .36 because I can't get any hard numbers for high racers.
That is: Watts to overcome air resistance at 13 mph = Cair .36 x velocity cubed 5.8 m/sec = .36 x 195 = 70 watts
On a slope the wind and friction become secondary to gravity because the rider is going slowly uphill.
Watts to climb = Cgravity x weight x slope % x velocity = 9.8 m/s (77.2 kilograms) x .06 for a 6% slope x velocity in m/sec
To make this useful to myself I changed it to find how fast I might expect to go on a given slope when producing 160 watts. That happens to be my max watts working just below my lactate threshhold.
That means velocity = 160 divided by (756.6 x .06 ) = 8 mph So climbing up Yarnell Grade between time stations in Congress and Prescott Arizona will take me, say 1hour 15 minutes at 8 miles per hour. I will need to do four hours going at least 14.5 mph to make climbing that grade average out to 13 mph, which is my target average speed. Since road engineers try to keep road grades at 6% or less I can more or less plan climbs at that speed. My speed drops .7 mph for each 1% increase in grade over 6%. Below a 4% grade velocity increases to where air resistance becomes significant.
Notice that climbing a hill is purely a problem of power vs weight. Going down the other side weight doesn't help as much as it hurt going up. Going down aerodynamics comes into play with a vengence. Most people can coast down a steep grade fast enough that maintaining control is more important than small increases in speed. In most cases bicycles just aren't geared so that pedalling over 25 miles per hour makes any difference.
As an aside, my trike with a Rohloff hub and Schlumpf speed bracket allow me to pedal against resistance at 35 mph. Much beyond that pedalling makes the steering wobbly.
A head wind is computed with (velocity + wind) squared. So going 13 mph into a 10 mph headwind requires:
.36 X (5.8 m/s + 4.5 m/s) squared x 5.8 = 220 watts, versus 115 watts to do 13 mph with no wind.
Now you know what your legs have always tried to tell you. That is what I did with my day today. Feel free to use it.
Useful numbers: 1 kilogram = 2.2 pounds 1 horsepower = 1000 watts 1 meter per second = 2.237 mph
5 mph = 2.25 meters per second 3 liters of water = 6.6 lbs or one big camelback
Average filled large water bottle = 1.6 lbs
ChrisM
www.mayq.com/Best_European_trips/cycling_speed_math.htm
The whole page can be expressed thusly:
WattsRider =Cfriction X velocity X weight + Cair(V + Vwind)^2 X veloc. + Cslope X weight X %slope X V + acceleration
It looks like a lot of stuff but it simplifies into:
Watts necessary to overcome friction = Constant value of friction, which is around .1, X velocity X weight
For me personally, that comes to .1 times 5.8 meters per second, or 13 mph times 77.2 my weight with bike in kilograms
I get 45 watts of power that I need to produce just to overcome the friction of the road and my weight on the hub bearings. The additional friction of chains, idlers, leg hair, cranks etc. is measurable but insignificant overall.
45 Watts for friction plus 70 watts to overcome air resistance at 13 mph = 115 watts to go 13mph flat, no wind
OR: Watts necessary to overcome friction = Constant value of drag times velocity cubed, assuming no wind.
I had to interpret the Cair, the constant value. An upright rider on a Mountain bike is about .9. A road racer in lycra and well tucked in is about .36. For recumbents the only measured value was for a Easy Racer Gold Rush at .046. I'll use .36 because I can't get any hard numbers for high racers.
That is: Watts to overcome air resistance at 13 mph = Cair .36 x velocity cubed 5.8 m/sec = .36 x 195 = 70 watts
On a slope the wind and friction become secondary to gravity because the rider is going slowly uphill.
Watts to climb = Cgravity x weight x slope % x velocity = 9.8 m/s (77.2 kilograms) x .06 for a 6% slope x velocity in m/sec
To make this useful to myself I changed it to find how fast I might expect to go on a given slope when producing 160 watts. That happens to be my max watts working just below my lactate threshhold.
That means velocity = 160 divided by (756.6 x .06 ) = 8 mph So climbing up Yarnell Grade between time stations in Congress and Prescott Arizona will take me, say 1hour 15 minutes at 8 miles per hour. I will need to do four hours going at least 14.5 mph to make climbing that grade average out to 13 mph, which is my target average speed. Since road engineers try to keep road grades at 6% or less I can more or less plan climbs at that speed. My speed drops .7 mph for each 1% increase in grade over 6%. Below a 4% grade velocity increases to where air resistance becomes significant.
Notice that climbing a hill is purely a problem of power vs weight. Going down the other side weight doesn't help as much as it hurt going up. Going down aerodynamics comes into play with a vengence. Most people can coast down a steep grade fast enough that maintaining control is more important than small increases in speed. In most cases bicycles just aren't geared so that pedalling over 25 miles per hour makes any difference.
As an aside, my trike with a Rohloff hub and Schlumpf speed bracket allow me to pedal against resistance at 35 mph. Much beyond that pedalling makes the steering wobbly.
A head wind is computed with (velocity + wind) squared. So going 13 mph into a 10 mph headwind requires:
.36 X (5.8 m/s + 4.5 m/s) squared x 5.8 = 220 watts, versus 115 watts to do 13 mph with no wind.
Now you know what your legs have always tried to tell you. That is what I did with my day today. Feel free to use it.
Useful numbers: 1 kilogram = 2.2 pounds 1 horsepower = 1000 watts 1 meter per second = 2.237 mph
5 mph = 2.25 meters per second 3 liters of water = 6.6 lbs or one big camelback
Average filled large water bottle = 1.6 lbs
ChrisM
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