This is mostly a question of "has this happened to you?" for other PowerBeam Pro users, but if anyone else wants to offer their opinion (or tell me my FTP is too low and my seat is too high) then please feel free to chime in.
I've been noticing two trends with my PowerBeam Pro over the past several months: the time to spindown during calibration is increasing and my perceived effort at a given power is going up, and both of these trends seem to be accelerating. For the first two years I had the PowerBeam the flywheel would take 11-12 seconds to spindown every single ride every season of the year (I use TrainerRoad and calibrate every ride). Around last spring/summer the spindown started creeping up slightly to 13-14 seconds and has increased more rapidly the past two months to 18-19 seconds. I don't really know if that means anything, but I've also noticed that my ability to hold power as measured by the PowerBeam has decreased as the spindown time has increased.
A couple other things to note:
• I obviously have the older, ant+ only version of the PowerBeam. Bought it in 2013.
• I've been using the same trainer tire on the same wheel on the trainer for as long as I can remember.
• Every once in a while I have a Stages on my bike while on the trainer. As the spindown has been increasing I've been seeing bigger and bigger differences between my Stages power and the PowerBeam. They used to be within ±5 watts of each other, but lately the PowerBeam is reading 20-35 watts lower than the Stages. (I can rarely get powermatch to work and I don't know why)
• I haven't noticed any comparable drop in power when riding outside, as measured by Stages.
On the one hand I don't much care. Since TrainerRoad bases everything off FTP I figure there shouldn't be an issue as long as I retest/update my FTP every few weeks. On the other hand it seems crazy to me that power I would ride during a 2x20 just before the holidays I now can't hold for more than 5-6 minutes!
Anyone else experienced a change in their PowerBeam over time?
I've been noticing two trends with my PowerBeam Pro over the past several months: the time to spindown during calibration is increasing and my perceived effort at a given power is going up, and both of these trends seem to be accelerating. For the first two years I had the PowerBeam the flywheel would take 11-12 seconds to spindown every single ride every season of the year (I use TrainerRoad and calibrate every ride). Around last spring/summer the spindown started creeping up slightly to 13-14 seconds and has increased more rapidly the past two months to 18-19 seconds. I don't really know if that means anything, but I've also noticed that my ability to hold power as measured by the PowerBeam has decreased as the spindown time has increased.
A couple other things to note:
• I obviously have the older, ant+ only version of the PowerBeam. Bought it in 2013.
• I've been using the same trainer tire on the same wheel on the trainer for as long as I can remember.
• Every once in a while I have a Stages on my bike while on the trainer. As the spindown has been increasing I've been seeing bigger and bigger differences between my Stages power and the PowerBeam. They used to be within ±5 watts of each other, but lately the PowerBeam is reading 20-35 watts lower than the Stages. (I can rarely get powermatch to work and I don't know why)
• I haven't noticed any comparable drop in power when riding outside, as measured by Stages.
On the one hand I don't much care. Since TrainerRoad bases everything off FTP I figure there shouldn't be an issue as long as I retest/update my FTP every few weeks. On the other hand it seems crazy to me that power I would ride during a 2x20 just before the holidays I now can't hold for more than 5-6 minutes!
Anyone else experienced a change in their PowerBeam over time?