Thread: Flying 200s
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Old 01-04-20, 02:12 PM
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Super D
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Originally Posted by Morelock View Post
So, I won't cover a full range of issues with stages reliability in data (i think the internet has done a sufficient job over the years) but something a bit more focused to track and sprinting.

In general the problems with track sprinting and power data (and the reason wired SRM's are still used) is "wakeup" and lag. Wakeup applies to your standing starts... the time from when you start applying force to when the power meter actually "wakes up" and decides to start recording. This is very important for timed events but for a sprinter in particular actually not "all" that important outside of a team sprint. Lag on the other hand is very problematic. Say you're winding up for a flying 200... applying constant(ly increasing) power for your wind up laps, which is something the Stages does handle fairly well... then as you start your sprint "proper" you suddenly go to 2-3x (+) the watts as you dive. The power meter takes some amount of time to figure out "oh hey, something different" and in those moments you're going to find the difference between a stages and a more "powerful" power meter.

In very short, violent efforts you need consistent, reliable data, perhaps even moreso than other forms of cycling. Stages do a passably good job for "most" cycling/cyclists... that is, averaging long stretches of relatively consistent power output. (most forms of cycling) The cracks show up in things like track sprinting, bmx, mountain biking where power shifts quickly and violently and often the spikes are so short that the average it spits out is flawed heavily by a misreading.

Somewhere in one of the threads on here (maybe the power meters for track thread) there is a stages rep who responds to some questions a few years back. He point blank says it's not really made for sprinters.
I found that thread, interesting discussion. Wonder if there have been any advancements at Stages since. It's a shame, I've had good luck (and service experiences) with Stages on the road bikes. Nice that they're affordable as well. (Granted, accurate is the most important factor, as carleton rightly points out.)

Originally Posted by carleton View Post
I think Stages is covered here: https://www.bikeforums.net/track-cyc...computers.html

Basically, Stages is designed for long road rides where what happens with one leg can safely be extrapolated to happen with the other...on average. Also, the sampling rate and wake up time are issues with track sprint efforts.

Yes, it's a power meter, but not one that's ideal for for recording Track Sprint efforts. Like when one needs to cut a steak and reach for a butter knife because you used it daily to cut butter and it was good at that.

It will be able to cut the steak. But, it's not the best knife for the job.
I planned a circuit road race finish using my power graph with Stages data for 45s and 30s power as a reference a few years ago, and while it wasn't as accurate as an SRM, it, along with analyzing the course shape and elevation changes, contributed to a solid finishing strategy. Not disputing what you've pointed out, rather matching an example of where it was helpful for longer sprint efforts, 400m+, in this case, unusually long. Decent tool for the job in that scenario.

The more I'm learning about gearing and cadence connected to speed objectives, the more I realize that those are my true must-have factors. If I'm not hitting the required cadence in the given gear combo, the speed simply will not be there.
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