Trainer accuracy

On my friend’s Cycleops Hammer my FTP is @135, which makes sense since his is a little over 200 and he’s a much stronger rider than I am. I mean, I’m 71 and average @15 mph.

But on my unsmart Nashbar my FTP is 208.

So I borrowed another friend’s (Yes, I have more than one) 1Up and had such a goofy ride in NYC that Training Peaks upped me to 291.

Help! Is there an un-smart trainer that is close to being accurate?? I’m thinking about a Cycleops Fluid 2.

Or should I just stick with my good old Nashbar and consider the numbers relative rather than absolute.

Thanks for any thoughts.


The Fluid 2 is a dumb trainer so you would need a power meter. You can use zpower with a Fluid 2 and this uses a known power curve to estimate the power. I’ve got a Fluid 2 and a Hammer along with several power meters. The Fluid 2 for me under reports power by 30 - 40 watts. The Hammer over reports power by around 2 - 3 %. Provided the Hammer has had a spindown calibration done recently I would go with that FTP. 291 is seriously fit for an older rider.

Probably one of the most debated topics on Zwift (and other platforms) @Don_Niederfrank. Unless you have access to a couple of correctly calibrated, consistently accurate power-meters the question is difficult to answer.

Unless your goal is to discover your own real FTP to a certain error percentage, stick to one machine and go with the relative data. Even if your Nashbar data is lower than you think it should be, it will still be a good relative indicator should your power rise or fall.

Be the best you can be on the equipment you have.

Ride On!

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Thanks to both of you for thoughts and insights.
291 isn’t just serious fitness, it’s absurd for me! There were times during that ride on the 1Up that my kw/g went over 6. That ain’t me, babe.

Paul this is a great piece of wisdom. You just saved me a bunch of money.

Again, thanks.


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