Originally Posted by
gsteinb
If I didn't have a PM I'd probably give Stages a go. For me it didn't make any sense to get a stages as a second. I got such a good deal on my second SRM that when you consider that I'd have to buy a garmin for it (unless I have bad info I couldn't pair a PC7 with a stages) that it would have cost me almost as much to get a stages (second bike so I'd need the full crank).
Yep, as someone who doesn't currently have a PM and has a small bike budget, Stages is pretty much the front runner as I contemplate a PM purchase. Stages has some known weak points compared to its more expensive competition, but they don't seem to be a problem for most of what people need a PM to do.
Originally Posted by
buzz_1919
First post, long time lurker who has learned a lot from you guys (thanks, by the way). Been racing in Tucson for a couple years. I have been using the Stages PM (Ultegra) since January. I did a little "experiment" earlier this year and I'd be interested in what other's thoughts might be...
Indoor on trainer, maintaining constant cadence, single leg drills (1-minute long each leg) at multiple power outputs (40%, 60%, 80%, 100%, and 120% of FTP). With the PM only measuring left-leg power, assuming an FTP of 250, the results *should* be:
[TABLE="width: 300"]
[TR]
[TD][/TD]
[TD]Both[/TD]
[TD]Left[/TD]
[TD]Right[/TD]
[/TR]
[TR]
[TD]40%[/TD]
[TD]100[/TD]
[TD]200[/TD]
[TD]0[/TD]
[/TR]
[TR]
[TD]60%[/TD]
[TD]150[/TD]
[TD]300[/TD]
[TD]0[/TD]
[/TR]
[TR]
[TD]80%[/TD]
[TD]200[/TD]
[TD]400[/TD]
[TD]0[/TD]
[/TR]
[TR]
[TD]100%[/TD]
[TD]250[/TD]
[TD]500[/TD]
[TD]0[/TD]
[/TR]
[TR]
[TD]120%[/TD]
[TD]300[/TD]
[TD]600[/TD]
[TD]0[/TD]
[/TR]
[/TABLE]
If the power ouput for the left-leg only portion is higher than expected, this would mean my right leg is providing more power when pedaling with both legs. Conversly, if the power output for left-only is lower than expected, my left leg provides more power. This would also show whether my legs provide different %'s of power at differing power outputs.
When I did this, my results showed that my legs are within the PM's 2% accuracy of being equal -- which of course was of great dissapointment as I was hoping my embarrassingly low FTP could be explained by my power meter's innability to accurately account for my incredibly strong right leg.
The new PM from 4iiii might be another good option to look at if anyone else is in the market.
I wouldn't have a great deal of confidence in that experimental design due to the fact that pedaling with one leg at a time is proprioceptively very different from pedaling with both.