I don't think there is a bad power meter on the market now, so it is probably best to choose based on other factors. I assume you are on a budget, so Stages and 4iii make pretty affordable single sided crank-based power meters. There isn't anything wrong with them, but if you have a discrepancy in power output between your legs, you could read a bit high or low on wattage. You are also stuck with the crank length you put them on, so make sure you aren't planning on trying shorter cranks.

I haven't tried the pedal-based meters yet, mostly because I only ride the Speedplay pedals and they are probably aero turds.

The Powertap hubs are what I use. They are simple, dual-sided, accurate and you can swap between bikes in seconds. The down side is they are part of the wheel, so you have to be willing on racing and training on the same wheel. I bought my first powertap as a used wheel for 200$. Now I have 3 Powertaps in different wheel sets, which isn't a budget option anymore. The other issue is you will be stuck if you ever upgrade to a disc bike.

https://www.dcrainmaker.com/...de-2017-edition.html

Nobody has more experience with power meters.

 

Powertap has the C1 chain ring powermeter on sale for $349.00


https://www.powertap.com/...wertap-c1-chainrings


DC Rainmaker has a review here:

https://www.dcrainmaker.com/...hainring-review.html


.

---

Once, I was fast. But I got over it.

I've considered this, but I can never tell if my bike is compatible

Powertap hubs are NOT dual sided. They simply measure total power (left leg + right leg). Dual sided PM's are those that allow to read individual leg power

That is an incredible deal. I use a C1 chainring and Wahoo ELEMNT Bolt and it's a great, great combo.

If your 105 crank has a 5-bolt pattern like this one http://www.chainreactioncycles.com/...hainset/rp-prod50444 chances are the chainring is compatible. Newer Shimano cranks have a 4-bolt pattern.

---

-------------------
Madison photographer Timothy Hughes | Instagram

While you are researching...

If you have a garmin watch, there is a free app in the IQ Store called vPower. Its a power data field that works in the same way that TR/Zwift virtual power works. It works both outside and on the trainer. I have been running it through tests over the last 2 months and its really good. Its matched the graphs of both TR/Zwift virtual power and the key is that its consistent with itself. While I wouldn't use it to say "my average power is 250 watts or whatever" to other riders you could use it to track your progress over time and during rides (really the point of power anyway). I think most riders could probably just use this and bypass a power meter altogether because of its consistency. The issue is that who knows if the dev is going to continue working on it, etc. so if he gets bored of it, it might not work in a year from now. But there is no reason that garmin or other companies can't develop a power app as TR/Zwift have done it.

Here is a link to it: https://apps.garmin.com/...b1-b80b-6b080940ebb7

*Im not suggesting you rely on this app and bypass getting a power meter. I think anyone serious should get industry standard stuff. But for recreational people and those with no other means to show power, I think this is a really good alternative. But its definitely worth testing out.

Usually P2's are delivered with FSA cranks

Ah. He didn't specify, just said 105. Regardless, C1s also fit FSA as the chainring is FSA brand.

---

-------------------
Madison photographer Timothy Hughes | Instagram

Correct, mine does have an FSA crank..I should have mentioned that...thanks for all the help!

Just curious if you got the C1 to fit on your P2, I also have a P2 and was looking at the C1. I emailed Powertap and they said it would fit but then on their Q&A section it says it will not fit BBright bikes, so I am not sure which answer is correct. Does anyone use the C1 on a P2? Not sure if the year matters but my P2 is a 2016.