cjj wrote:
Even if you had the same (unit) power meter on both bikes I'd have an FTP that was bike specific. Throw in to the mix 2 different units of the same brand of PM and there is the possibility for even more variation between the two setups so I'd want a bike/pm specific ftp even moreso. Now throw in 2 different pm units of differing brands, l/r issues, etc on a road bike vs a tri bike and I would definitely want specific ftp's for each bike/setup.
I personally set up mutliple users in Golden Cheetah (TT Inside, TT Outside, RB Inside, RB Outside) b/c my power curves are very different in each of those 4 scenarios.
CJ
All of that above is completely unnecessary if you purchase a power meter that allows for at least the check of the torque slope (i.e. PT, P2Max?) or even better, allows the torque slope to be calibrated with a known weight (i.e. SRM, Quarq, etc.)
I have 4 different Quarqs (a Cinqo, 2 Reds, and an Elsa) on 4 bikes and they all read identically. I know this because I've calibrated the torque slopes myself. I also have an MTB PT hub and an old yellow cap PT Pro that both read accurately as well (as determined by a torque slope check).
Like I said, this is one of the main reasons that some of us beat the drum about not settling for power meters that aren't accurate and precise.
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