I Fired Zwift FTP Tests
03-28-19, 08:57 PM
#26
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why not use your powermeter with powermatch on zwift? The more likely issue is that the smart trainer and power meter readings do not match, which is not a zwift issue, its a trainer issue. I use my PM on zwift so my numbers stay consistent indoors/outdoors. My smart trainer reads about 10% low, yours seems to read high. The zwift FTP test simply uses a incline/slope mode during the 20 min testing portion of the test so its not that different in practice compared to the road.
Then I compared the power meter on the bike to zwift power. I again had a higher power on Zwift than I did on the power meter. It wasn't as drastic at 50 watts like I had before but it was still 25-30 watts higher on zwift than on my bikes power meter. I really wish I could compare my trainer software to zwift numbers but it will not connect to more than one device so that is not an option.
Finally I did the short FTP test. (20 minutes). But I didn't go all out, I went for more of a consistent power as to compare. I did a cadence of 80 in the same gearing for the test. My bike power meter was 204 for that 20 minute session, zwift was 227. Zwift was again higher for at around 10%. I just don't think that zwift is super accurate. BUT if the main point of this is if you use zwift and always compare the zwift numbers its fine because you then it measurable, you just can't use zwift and a power meter and a strava algorithm to compare everything with and get solid numbers.
I still can't explain the higher reading from last year. I think maybe there was a trainer issue because there is just no way I am that high.
FWIW when I have done "races" on zwift my power is never any higher than any other time. I might push harder but I don't think I am making anymore power.
03-29-19, 07:28 AM
#27
meh
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This is interesting, thanks for the info!
I'm not riding with power outside, so I'm not comparing real vs Zwift. (I plan to add power to the N+1 this summer).
IMHO - as long as Zwift's FTP and power is consistent, it's good. I would never take Zwift FTP into the real-world or visa versa... too many variable between an indoor/outdoors set up.
This is also why I've been using % changes and not the watts, I don't trust Zwift and my trainer (Kurt Kinetic) to be 100% accurate, but I do expect them to be consistent.
I'm not riding with power outside, so I'm not comparing real vs Zwift. (I plan to add power to the N+1 this summer).
IMHO - as long as Zwift's FTP and power is consistent, it's good. I would never take Zwift FTP into the real-world or visa versa... too many variable between an indoor/outdoors set up.
This is also why I've been using % changes and not the watts, I don't trust Zwift and my trainer (Kurt Kinetic) to be 100% accurate, but I do expect them to be consistent.
03-29-19, 10:22 AM
#28
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This is interesting, thanks for the info!
I'm not riding with power outside, so I'm not comparing real vs Zwift. (I plan to add power to the N+1 this summer).
IMHO - as long as Zwift's FTP and power is consistent, it's good. I would never take Zwift FTP into the real-world or visa versa... too many variable between an indoor/outdoors set up.
This is also why I've been using % changes and not the watts, I don't trust Zwift and my trainer (Kurt Kinetic) to be 100% accurate, but I do expect them to be consistent.
I'm not riding with power outside, so I'm not comparing real vs Zwift. (I plan to add power to the N+1 this summer).
IMHO - as long as Zwift's FTP and power is consistent, it's good. I would never take Zwift FTP into the real-world or visa versa... too many variable between an indoor/outdoors set up.
This is also why I've been using % changes and not the watts, I don't trust Zwift and my trainer (Kurt Kinetic) to be 100% accurate, but I do expect them to be consistent.
