I bought the Rally XC 100 pedals for my 2021 Checkpoint SL5 and am happy with them.
Hi,
thanks a lot, i bought the 4iii left crank 105 and it fits nicely on my GRX. Actually I dont cant see or measure any difference at all in angles, distance between crank and frame etc.
Did a first indoor ride in my rollers and yes, it works.
In the past I have
- used a Kickr 2017 (sold it)
- or Rollers with TR Virtual Power (cancelled)
- or the Elite Misuro on my Elite Rollers (something like VR) - used it until today
Now it is the 4iii on my Elite Quick Motion Rollers.
It is probably too early but so far the 4iii seems very jumpy. I am riding pretty smoothly IMO but sometimes the power data jumps by 20-40watts for a couple of secs. Yes, probably 3sec or even 10sec watts make more sense to put as a data field on my Garmin Edge, but anyway:
Is it normal that power measurements fluctuate that quickly and much? I did not have that on my Kickr with TR
Thanks in any case for the great support. 200ā¬ for a 4iii is a great deal!
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Welcome to life with a āreal power meterā. The nature of how and where it measures power will appear very active compared to any of your prior methods.
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Looking at the prior sources you had, they all have the tendency to show what I consider ādampedā power data. It is generally delayed and smoothed in ways that are part of how the data is captured in the first place. Even if you had the Kickr in Resistance mode, or ERG mode with smoothing turned off, it is still a bit slower in response compared to power at a crank.
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You can consider adjusting the smoothing value in apps and such, but do note that in the TR app, that only affects the digital display of power. It does not alter the actual data captured, or the graph based upon that data.
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In short, you get used to the new, more jumpy data.
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thanks a lot, Chad - helpful as always
So probably 1sec and 30sec datafields on my Garmin dont make sense, rather 3 or 5sec - right?
Depends on the actual meter and rider preference, but a power data smoothing from 3-15 seconds seems like a common range. I am in the 5-7 second smoothing IIRC.
Not sure specifically on the Garmin or impact there, because I donāt have one of their head units.
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Which Garmin do you have? I find it easier to look at the real-time power graph. You should have 3, 10, and 30 second averaging fields available under the Power sub-menu. Do you have a workout loaded? With Garmin and TrainingPeaks workouts loaded you have access to nicer real-time power graphs, which ironically makes Garmin/TP workouts on my 530 more like the TR app.
Regarding jumpy powerā¦ If you ever look the Strava power graphs of Pros doing training sessions, youāll see many/most of them have an amazing ability to keep power smooth even in undulating terrain. Keeping smooth power in undulating terrain is really hard for me! It is definitely a skill.
However training on steady climbs and flat terrain, my outside power graph looks the same as Kickr 2017 with power smoothing disabled (in either Erg or Standard/Level/Slope modes). Last night I made a new segment in WKO and was looking at some rides from 2016 when I first put a Stages left-only power meter on the bike. My pedal stroke was pretty smooth back then, but from statistics point-of-view (standard deviation) its 3-5x smoother now. Regardless of the terrain, you can improve!
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Hey, the two forum veterans jumping right in giving great advice. Thank you.
I have a 830 and recently bought a 530 too. I exclusively use those two devices, no TR app, no mobile, just the Edges as Bike Computer outdoors as well as indoors
I will probably go with 10sec datafield and try to work on the smoothness. That is a quite unexpected new challenge and goal for me. Motivating 
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are you just riding outside, or doing a workout from memory or a piece of paper?
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I was with TR but now do a mix of outdoor/indoor in Summer, in European winter only indoors, following Garmin workouts or design my own using Garmin Connect. Works great.
I do some indoor rowing and walking to balance all that.
Outside these are my two favorite screens while running a Garmin or TrainingPeaks workout on my 530:
^^ Garmin Default Workout Screen
Both do a good job at taking my mind off the short variations in power. And both default to showing 3-sec power.
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does anybody have a link on how these crank based PM like 4iii etc work?
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one week in I am really enjoying the riding with a real power meter. gives me much more confidence riding my rollers and a better feeling where to go from here with my indoor winter trainings.
thx again for all the input here
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Hi! Just bought the same exact bike, and I could really use your help. What do you recommend me in terms of power meter for the bike? I am in the same situation you were: the bike comes with the praxis crankarms, and I was wondering if I could replace the left crank for a 105 / ultegra / grx 4iiii/stages left crank. Please, help me.
Thanks
Well yeah power meters are jumpy, but onesided crank ones are even more jumpy , and single leg ones off road are even more jumpy. I set 5sec power PRs like every rough down hill.
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Power2max
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just curious, have not tried it yet: does the 4iii crank also provide cadence data?
I put my cadence sendor on the crank and never thought about that I might not need it.
thx
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Yes it does. It needs to measure cadence to calculate power. Iām not sure about the 4iiii but the stages didnāt transmit it as a separate channel, it seemed to be embedded within the power ant+ channel.
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Yes, cadence is needed for power calcs, and it will report that cadence to any device it is paired toā¦ unless there is an actual cadence sensor paired as well.
In the case of YR at least, it will takes the data from the ābestā source and it places a cadence sensor above a power meter AFAIK.
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Power meters usually provide cadence data, just try it out
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