Shimano Power Meter (R9200P): How is it this bad?

Here's a deep-dive into the Shimano DuraAce R9200P power meter, and whether or not its accurate. I go through 8 months of data, from multiple units/people.

I’ve been testing the Shimano latest generation power meter since last summer, comparing it to virtually every other viable power meter and smart trainer on the market today during that time frame. And as one who tests power meters for a living, it’s glaringly clear the Shimano R9200P follows in the footsteps of the previous generation Shimano power meters in one key area: It’s horribly inaccurate.

Mind you, this isn’t just one unit, or just my test unit loaner provided by Shimano. Instead, it’s looking at data from multiple units, sourced from multiple bikes, on multiple continents. Data which is supported by numerous WorldTour Pro cycling teams and other pro riders reaching out after seeing their own data issues. It’s a constant yet frustratingly inconsistent pattern of inaccuracy that I’ll outline in the data section of this review.

However, before we get to that – a quick and unusual preface.

Normally, my reviews are pretty long and detailed – be it for a power meter, smart trainer, or anything else I cover. These reviews usually cover all aspects of the product: From unboxing, to installation, to general use features (like the app, connectivity, etc…)…all sorts of stuff. The point of all that extra stuff being to help people understand all aspects of the product, so even if one portion of the product isn’t to my liking – it might be to their liking, and thus, the review is still useful to them.

However, in the case of a power meter, the *ONLY* thing that matters is accurate data. Or, at the very minimum, consistent data. In this case, it is neither accurate, nor consistently offset (not ideally either, but sometimes workable). The parameters for when and why it’s inaccurate vary within a ride. Thus, all of the typical review components (unboxing/install/app/etc..) simply don’t matter because I can’t see any viable electronic use for this product. And pro teams agree too – they’ve been actively trying to avoid using it for training and racing, but most are bound by Shimano sponsorship agreements. Despite that, we do actually see some top Shimano-sponsored pro teams using alternate power meters on their R9200P-equipped bikes.

Thus for this review, I’m just going to focus on the single thing that matters here: Power accuracy.

0:00 Quick Overview
1:03 The Small Chainring Problem
3:42 The Rightside Problem
5:40 The Soft Pedaling Problem
6:55 The Forever Power Problem
9:04 The Power Meter Poison Chart
10:00 Can Shimano Fix It?
11:19 What about Pro teams?
12:11 What should you do?