Tuesday, March 27, 2012

A techie bike and trainer question

Once I got home after dropping Linda off, I consulted my list of things to do. I was even about to nuke a cup of coffee to help me decide. Then I realized that if I sat down to think about it and drink my coffee I was going to go to sleep. So I crawled back into bed, still warm from when I made it, and slept like a rock for 3 hours. How nice.

From there I woke myself up with a nice core session. Sort of. The waking up. And the core session too, I guess. My legs are still feeling tired. Then on the bike for a slow warmup.

Tried a new thing. Stayed in one gear and gradually increased the brake. Each increase ups the wattage output by about 10 or 12, assuming the rpm stays constant. Which I was trying to do. Pedaled 8 hard, and 2 easy. By the fourth one I was feeling distinctly feeble. Bailed out and cooled down. 1.25 hours.

Here's the bike and trainer question. No idea if it has been answered elsewhere.
When I bought the trainer I set the bike up on it and calibrated the power meter per the instructions. It didn't say anything about periodic recalibrations, so I've just left it. Today I pumped up the tires since they were getting a bit soft. That is the ONLY thing that has changed since my last ride.

Does increasing the pressure in the tires alter the rolling resistance on a trainer? If so, up or down, and by how much? Or in other words, am I going to have to work harder, or not as hard, to achieve a given wattage after pumping up the tires?


  1. Oh goodie! Something I actually know a little about...

    Now all I can do is tell you about the Computrainer, but I think the same principles apply. I recalibrate every time I ride my bike. I also pump up my tires to make sure they are the same pressure (not before every ride, but every second ride.) After every ride, I unscrew the resistance thing and clean the roller/drum thing and my rear tire with a cotton swab moistened with rubbing alcohol. If you are using the trainer to compare your workouts and watts, etc, you want to strive to make sure the conditions for each ride are identical (or as close as possible) to give you accurate readings.

    I don't know if you will have to work harder or not now that you have pumped up your tires...but I think you are about to find out! Hahahaah!

  2. Hmmm. Interesting. I just looked at my roller/drum thingie, thinking, what could be on it? I washed the tire before installation, and the trainer has only been set up outside the house once. The bike hasn't been ridden outside since I got the trainer. What could be on it besides household dust? Yeah. Rubber dust. A mound of it. I need to clean the guck off, and will do that before the next ride. I'll have to find the instructions again to recalibrate, that's probably a good idea too. Thanks for the info!

  3. By the way, I meant cotton ball not cotton swab. LOL


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