So I know a lot of people don’t really care about the left/right balance but I’m looking for a dual sided power meter with a trusted left/right balance and came upon the p2m ngeco and read a bunch of review’s where it said that it’s not really right/left balance but rather calculated some how. Any advice?
Any spider based PM will give you a rough estimate based on the clocking since it can track torque applied based on cadence position sensor.
What it can’t do is tell you the exact percentage of the torque at an existing clock point from each crank arm, even if it can detect slight shift one direction or another across the strain gauge. So if you are on the power stroke on the right foot, it might be able to understand that most of the torque is coming from your right foot, but won’t be able to get an exact breakdown if you are also pulling up with your left foot.
It will be good enough to detect large imbalances, but not to the level that you would get with a true dual sided solution like pedals.
IMO, it’s not really worth it unless you believe you have some large inherent imbalance from injury or existing body mechanics.
So technically it’ll be better to just buy a cheaper left sided pm instead of the p2m ngeco and save some money?
I haven’t had good experiences with the single crank arm based power meters. A spider based PM or dual-side crank arm meter will be more reliable for overall power. Part of this is specific to me, which is that I descend on my mountain bike with my left foot forward, which generates large power spikes.
That being said, if it’s for a road bike, a single left crank is probably good enough.
I have the P2M and enabled the L/R feature because it was a freebie tossed in by my cannodale rep.
I also have a bike with a 4iiii left side only PM.
I was seeing big discrepancies between the two during independent rides and I cou;dn’t figure out why until i actually went and looked at my L/R %. I am 44/56 typically.
My 4iiii was giving me ~290w FTP while my P2M was showing ~325
The only thing I can point to is the left right imbalance that I clearly seem to have. And it aligns very closely to the % that my 2 power meters seem to kick off.
The spider based PMs are detecting your left right balance by assuming the deadspot in the pedal stroke is where you are switching from left to right foot power. Therefore, if you are pulling up with the other foot, it won’t give you proper values. If you are needing true left right balance, then a pedal based PM is the best option, something like a Favero Assioma.
Even if the left/right balance is untrustworthy, due to the assumptions it makes relating to your pedalstroke, you are still getting the correct total power.
In a left only PM you only measure half so won’t be as accurate.