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Old 10-07-2012, 02:14 AM   #5 (permalink)
Piwoslaw
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Join Date: Oct 2008
Location: Warsaw, Poland
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Svietlana II - '13 Peugeot 308SW e-HDI 6sp
90 day: 58.1 mpg (US)
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I haven't seen BSFC maps for biker legs, but I have noticed that
  • Brisk acceleration makes me tire quicker than slow acceleration,
  • Coasting allows my legs to rest.
Both of these are specific for the way that living organisms work, not mechanical engines. The reason that P&G works in a car is it allows you to use the engine only in its most efficient rpm/load range, while turning it off for the rest of the distance. The engine is killed not because it needs to rest, but because it is not needed at the moment. The most efficient setup would be to downsize the engine so that your whole trip is one long pulse, ie the engine is at optimal rpm and load for the whole duration. But this isn't possible in the real world, so P&G is the next best option.

Quote:
Originally Posted by HyperMileQC View Post
My bycicle computer records calories even if I am coasting. My theory about it's recording, is it adds or remove calories if I go faster or slower than my average speed.
So according to your computer, you are burning the same amount of calories whether you are coasting downhill or sweating your pants trying to keep up speed going uphill. If so, then you computer is just plain wrong

Quote:
Originally Posted by bikin' Ed View Post
Rider position is about 80% of aero drag, so keeping you body exactly the same for all of those rides is going to be tough.
If the bike comp only inputs speed, then aero position won't effect its calorie display.

Without complicated equipment (monitoring heart and breathing rate, how much oxygen is used in each breath, how much power you need, etc.), it will be hard to get any kind of accurate data. The best simple test that I can think of at the moment is to see how far you can ride your bike. Do this every 2 days (allowing a day of rest between tests), and you will have to alternate between P&G for the whole distance, or steady speed. Do this for 2-3 months to take account for your physical condition improving, and for weather variations. Then you will see if you tire quicker when P&Ging or steadly pedalling.

Quote:
Originally Posted by HyperMileQC View Post
A will be riding at an average speed of 20 Km/h without P&G, and B will be riding in Pulse and Glide from 10 Km/h to 30 Km/h.
If you P&G between 10 and 30 km/h, then your average will be less than 20 km/h. So, first P&G, then set your steady speed to the average you had while P&Ging.
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