Questions galore from this inquiry.
Will it go on a road bike, gravel bike, hybrid, or MTB?
Do they desire double-sided measurement?
That said, the quick-and-dirty:
If they ride a road bike, the best bang-for-the-buck is the Magene PES P505 Base power meter. It is a crankset that uses the Shimano 24mm bottom bracket standard and 4-bolt Shimano-standard chainrings. It’s rechargeable and takes double-sided power readings via the “spider” that holds the chainrings. One charge lasts a long time. I’ve been running one since May 2024 and even with over 5,000 miles of riding since it’s only needed to be recharged once.
The basic meter without chainrings or BB costs $300. Chainrings are another $80-140 depending on whether you go with Magene’s rings or something else (Shimano rings are pricey but shift much better).
If they ride a gravel bike, MTB, or hybrid your best bet is a single-sided SPD-standard pedal system. Favero makes the best of these, followed by Garmin. The Favero units have a rechargeable battery (completely sealed), while the Garmin pedals use a replaceable battery. Favero pedals are held in very high regard by most people for reliability and quality data. Both Favero and Garmin single-sided pedal sets can be upgraded to double-sided in the future, if that matters.
(Favero’s road pedals are also really great, but the Magene crank-based power meter is every bit as accurate and a lot more affordable.)
FWIW: I run Favero pedals on my gravel bike and they are bombproof. And I used to run a Stages single-sided power meter on my road bike until I upgraded to the Magene unit. Note that Stages isn’t around anymore, though Giant may bring them back in the future… maybe.
I hope this helps!
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