Whilst it isn’t as accurate as using a direct force power meter (and really is no substitute), with a little cunning you can keep your PowerCal spitting out consistent numbers as your fitness improves.

I’ve been training with a PowerCal for ~1.5 years now. Out of the box I was thrilled with how well it appeared to work. I was getting great power out-put and the numbers were consistent for the effort I was putting in and my heart rates.

The more I trained though, the more problems I had. As you train and get really fit your max heart rate can actually drop by up to 10 beats per minute. Also you will be able to put out more power with less strain on your heart. So more watts, less bpm’s. The PowerCal does not like this! And pretty soon you will start to see your watts drop. Despite the fact that in reality, you’re getting stronger.

I thought the only way I could get anywhere near accurate power figures again was to spend £££’s on a direct force power meter. I really want a stages but none are available.

So here’s another option. No, it still isn’t perfect, but yes it’s better than nothing!

  1. Download and install PowerAgent.
  2. Find a direct force power meter. I used a Wattbike at a local gym but you could always hire one, or borrow one from a friend.
  3. Then do the necessary tests to get your power data. There’s some great info on this at Flamme Rouge.
  4. Upload the data to PowerAgent.
  5. Recalibrate your PowerCal based on the new heart rate and power data.
  6. Repeat as necessary.

I’d recommend doing this every 6-8 weeks or after a heavy block of training to make sure your PowerCal isn’t drastically underestimating your fitness / power!

And just in case you bugger things up and want to reset – here are the default factory powercal calibration parameters

A: 2.550
B: -190.0
C: 150.0