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I can't easily change my crankset or hub, so I'm looking at pedal power meters. All of them (PowerTap, Garmin Vector, bePRO, Xpedo Thrust-E) use Look/Keo/SPD-SL cleats. For me, walkable riding shoes are a must.

Are there adapters from Look/SPD-SL to SPD cleats? Is there another solution to this problem?

ETA: I said I can't easily change by crankset or hub. Please don't reply telling me to do that. The reason being, I have a Pinion gearbox which doesn't take custom cranks, and I have a 158mm rear axle which hub-based power meters don't fit.

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    Roll your own: instructables.com/id/Bike-Power-Pedal-IoT – R. Chung Oct 30 '17 at 17:49
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    The reason solutions are hard to find is that almost all power meters are made for road bikes. There’s little market at the price point that a MTB hardened power meter would sell for. Road biking is about continuous power over long periods of time, where a power meter is useful. MTBing is about instantaneous power in which a power meter is less useful. – RoboKaren Dec 15 '17 at 0:29
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Not answering your question directly, but this is too long for a comment.

There are other places to put a power meter than your pedals/cranks.

  1. In the wheel hub , example is https://www.powertap.com/product/powertap-g3-rear-disc-hub. Downside is they're not cheap at $600-$800 USD, plus you need to build them into a wheel so not easy to move between bikes

https://www.powertap.com/Uploads/Powertap/2015/3/hubs_g3_disc_142mm_thru.jpg  from above web site

  1. Not a solution for you, but its possible to put the power meter in the cleat. http://www.magnes.ch/sports/ Sadly its a road style and isn't overly walkable.

http://www.magnes.ch/wp-content/themes/magnes/assets/image/features.png from website above

  1. Leave the power meter completely away from the transmission... http://www.powerpodsports.com/ is a wind-based power meter. I have no idea how it works, but at $300 its also half the price of other power meters.

http://www.powerpodsports.com/wp-content/uploads/2016/05/PowerPodBlackCombo020216.jpg  from their website

  1. Last resort is to use Strava's power guesstimate. Its pretty useless for peak power or instant power, but over the course of a ride, the average power seems "reasonable" as an estimate. Main bonus is this is free.

In addition there exist chain-based power meters, which "listen" to the chain electrically like a guitar pickup. They seem uncommon now.

  • I can't use a crank-based solution because I have a Pinion gearbox and it doesn't take custom cranks. And I have a wide 157mm rear fork which the Powertap hub doesn't fit. Chain-based meters AFAIK are not being produced any longer. That leaves the Powerpod. That's probably my best remaining option, but it's less reliable offroad. – danarmak Oct 30 '17 at 8:53
  • You might find a crank based power meter for the left crank which can normally be removed on any system and has a standard interface. Google: 'crank based power meter' or check the stageONE website.or this review: dcrainmaker.com/2012/09/… – Carel Oct 30 '17 at 12:59
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    Some companies offer a service where you send your own crankarms and they install powermeter onto it. @danarmak wouldn't this work for you? – Klaster_1 Oct 30 '17 at 14:09
  • I think that only works if the crank arm is of a certain construction (e.g. hollow aluminium). I don't know if the Pinion crank arms are compatible with any given company, and don't particularly want to ship abroad to find out. – danarmak Oct 30 '17 at 21:06
  • I'd guess the wind ones are as good as just getting the speed of the bike from a speed sensor and just doing some math. – Batman Oct 31 '17 at 0:12
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See this question for how to make a SPD-SL/Look pedal a flat platform. There are adapters for SPD-SL or Look shoes to SPD for using the other cleat, but you need the portruding cleat to engage/disengage a look/spd-sl style pedal. So, you can't clip in with something walkable on a SPD-SL/Look pedal.

SPD pedals are a bit tricky to fit a power meter inside just cause they're typically quite small pedals to begin with. Also, I think there may be some patent issues (which I think held back SPD-SL from getting power meters); maybe someone can verify this.

Getting a crank power meter is probably the easiest and best option.

  • I know I can convert Look pedals to flat platforms. But can I convert those platforms to SPD? And would using two converters be rigid enough? – danarmak Oct 30 '17 at 8:52
  • No. You'd have to basically attach a SPD pedal to the flat platform, and you probably can't do that in a safe manner. Also, theres a chance it'll add enough noise / play to screw up your power measurements. R. Chung's comment is probably the best you're going to get -- your likely best bet is to hack together your own. – Batman Oct 31 '17 at 0:14
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I conclude there's no adapter from road to SPD pedals. I will have to solve my problem another way.

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    You've been given a bunch of ways to solve your problem. I feel there's something you're not telling us, like that you already own something not-stated and its skewing the requirements. – Criggie Oct 31 '17 at 19:38
  • To be honest, I have seen answers with solutions that either do not measure power or don't fit the OP's rather weird bike. – ojs Nov 3 '17 at 7:31
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I have a speed sensor that straps to the hub and also calculates power. Is this not an option?

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    Straps to the hub? That's new to me... can you please quote a brand name to google ? – Criggie Nov 3 '17 at 1:34
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    You can't calculate power using only speed. – ojs Nov 3 '17 at 7:30
  • This answer needs to be longer, and have a lot more detail to be useful. Please expand to at least 4 lines of text in your answer. – Criggie Nov 3 '17 at 7:35

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