There are so many power meters out there that it is difficult to chose the “right” one for you. I don’t do too many product reviews, however I think it might be helpful to do a simple breakdown.
- SRM – This is the power meter that is built into your cranks. The SRM power meter has widely been known as the gold standard. Both for accuracy and for quality. It is also the most expensive and had been heavier than others. The software is incredibly difficult to deal with and has so much data that it becomes difficult for the recreational cyclist to use. Of course now there is WKO from Training Peaks that takes care of any proprietary software issues. It does require a roll out to ensure accuracy, which isn’t too big of a deal if you remember.
- Power Tap – The rear hub power meter. I would say this is the most popular power meter out there. It is a reasonable price, not terrible weight, and has pretty good accuracy. The reliability is OK, but definitely not great. I have seen a difference between hubs when a rider swaps between wheelsets, so the accuracy seems to be consistent within the hub, but not universal. The biggest challenge with this power meter is that it is tied to a wheel. So if you have a separate training wheelset from racing, you will have to choose which set to have with your power meter. As a coach it is nice to have the data all the time and sometimes racing is the most important. So it can become more expensive if you need two wheelsets or more. Especially considering that time trials are really good opportunities to use power to your advantage in a race. If you race a disk wheel, having a power tap hub for this specific purpose starts to get expensive. The software is pretty basic, almost the opposite of the SRM. It is really paired down for ease of use, which is helpful for the rec cyclist.
- Quarq – These also are incorporated into your crankset, but as an add on instead of integrated like a SRM. The original series of these power meters were not terribly good with accuracy and dependability, however the latest renditions seem to be much better. Many racers I know love these and their price is much better than a SRM.
- Polar – There are two Polar options. One based on chain tension and the other integrated into the pedals. The chain tensions system had some problems with accuracy and was a pain to install. However it was a nice option for affordability. The software is top notch and easy to use. I think this system is being phased out to make way for the pedal system. The pedal system is a shot at the holy grail of power meters. A light weight system that is easy to move from bike to bike, ensuring use in all situations and on all your bikes. You do have to buy into the Look pedal (a problem for me because I love my Speedplays). The cost is reasonable, but on the higher end. One thing that Polar does much better than the other HRs attached to the other systems. There seems to be a pretty good weight advantage here since the pedals and power meter weigh 400 grams together. My Dura Ace pedals are 300+ grams alone. I don’t have any personal or coaching experience with the pedal system yet.
- Stages – There is a lot of hype about this new power meter that is integrated into one of your crank arms. The weight seems to be really good and the installation is as simple as installing a crankset. All the reports on accuracy are very good. Because it is on the non drive side, moving between bikes should be very easy as long as you use the same size/brand crank on your other bike. This could be the giant killer and really take off. Pricing is in line with Power Tap and therefore very competitive since it has other advantages. It is brand new and therefore I have no idea on durability, etc. I have no personal experience or coaching experience with this power meter. Although, this is the first one to come out in a while that has me thinking about buying a new power meter. There are some compatitiblity issues with certain frames that have too wide chain stays.
- There are a few others out there, but I don’t have too much experience with them and I don’t seem them out on the race scene much. These include: ibike, Ergomo, and Garmin Vector (still to be released).
At this point in the evolution, they are all pretty good. It comes down to a balance of price, weight, variability of use, and reliability. I can’t over emphasize the reliability issue as being one of the most important. It is pretty frustrating to have to mail bike parts all over to get stuff fixed, especially if it is a critical part of your bike.