Home› General Training Discussions

Powertap on trainer...

kurshingkurshing
in General Training Discussions

I am new to power training as of about 2 months ago.  I have a Powertap and when I am on the trainer, I am having 2 things going on that I am curious about.

#1 - It says I am going around 75 mph...now, I AM fast (sarcastic), but I can't take credit for that amount of speed!

#2 - When I am just pounding it, I swear I am not getting credit for my efforts as far as power readings are concerned.  In other words, I feel like I am putting out 280-300 watts of effort, and am getting most like 215 watts as my reading.

Am I just needing get my head around how much harder the work is on the trainer, or, does it sound like something about my trainer set up and Powertap is weird?

Thanks!

Comments

  • tuckermtuckerm
    Steve,
    Needless to say the 75mph is wrong. No idea how to help there. Has it always shown ridiculous mph?
    As for the watts, is this your first time on the trainer? What's your FTP? Are you using a fan to cool you off on the trainer? What are you using as your basis of effort to compare to the trainer?
    And here's my help desk response, do you have the resistance against the back wheel?
  • kurshingkurshing
    It didn't always show that ridiculous mph on the trainer just recently. Outside it is normal.

    Yes, I have resistance against the back wheel.

    My FTP is 240.

    I have ridden outside and inside with power for about a month and a half and it just seems like 200 watts on the trainer is sbout the equivalent of 250 on the trainer...I COULD be mistaken, but, I really feel like there is something going on.
  • deleshdelesh
    Sounds like your wheel circumference number might be out of whack and causing it to read super high speed. Also, try recalibrating the powertap to see if that helps with the power readings.
  • HayesSanbornHayesSanborn
    Crack the resistance down on the trainer more and see if the numbers improve. Inflate your tires to the normal amount.
  • Nemo BrauchNemo Brauch
    or just ignore speed on the trainer. It's not going to be accurate anyway :-)
  • kurshingkurshing
    @ David & Hayes...will try both of those suggestions, thanks!

    @ Nemo...ignore the speed? That was the most encouraging part! LOL. No, it was the speed being off, in conjunction with the power seeming to be off that made me think something was up. I BET David got it right with the calibration. When I ride outside, after about 30 seconds, every time, my Garmin 310 says 'Wheel size calibrated'...like, maybe it does it when I am outside riding, utilizing GPS and the Powertap input, but, inside it doesn't have the ability, could that be right?

    I don't know...either way, I am going to try waht David and Hayes said and I am betting that gets it straight!

    Thanks all!
  • Nemo BrauchNemo Brauch

    Steve, ahhh, you didn't mention before that you are using a Garmin 310 as the computer for your Powertap.  I was assuming it was the LYC (stupid to assume of course). 

    Highly recommend you check out this blog post with great information about training with your garmin indoors and things you need to consider:

    http://www.dcrainmaker.com/2010/01/...armin.html

     

  • kurshingkurshing
    aaaahhh...thanks Nemo. That is a great little forum discussion!
Sign In or Register to comment.