Power Meters / Powermeters (SRM, Powertap, Quarq, Ergomo, Vector, Stages, power2max, P2M, 4iii, InPower, Cinch)

In which case I need to work out how to update my firmware!

Hippy and normal day to day use. Lol.

Tested to destruction more like

TCR isn't what I'd call normal, but yes.

If you haven't got a Pioneer head unit, you need an ANT+ dongle, a laptop and an exe from Pioneer support. I've got the exe kicking around somewhere if you want me to email it over or something. Was the latest version as of a month or two ago.

using a p2m (not true left right power) my power is consistently around about 47%/53% balance.

It doesnt level out when doing max efforts, eg I did a hour effort today that was a 60min power pb and my balance was 47/53. 5 min effort the other day was 48/52, 3hr club ride 48/52 etc

Does it matter, is this within a normal range or a within the % of error that p2m esimates l/r balance. Anyone else with a p2m find it similar? Any other potential causes, short leg? tight hamstring etc?

It doesn't matter a jot.

Does it matter, is this within a normal range

No, yes.
If it changes a lot, there might be some significance to it, but the chances are that you'll already know you have a broken leg without looking at your power meter :)

I was mostly wondering if it was a fit issue as from the limited amount I've read , normally it gets closer to 50/50 at max effort

I have found (anecdote klaxon!) that if I travel somewhere (Colorado normally, although I may not go there again now), put the bike together in the hotel room and head out then it's a sign that I've not put the seat at the correct height if the power is 45/55 or whatever.

Fiddling with saddle height normally brings it back to an average of 50/50.

This is with a Pioneer which is true left/right.

from the limited amount I've read , normally it gets closer to 50/50 at max effort

It's already close at low effort, so there's limited headroom for the gap to close up as the effort level rises.

My P2m used to do this, suggested my right leg did 5% more work than the left. Then I bought a second p2m and it showed the same trend, but with the opposite leg... So take from that what you wish.

LHD?

I have wondered what would happened if I put it on backwards on our tandem. Would it work in reverse and give us total tandem power?

Problem would be the auto zero, get the track one and I reckon it'd work.

Mind you, pedal based would be much more straightforward

Mind you, pedal based would be much more straightforward

Wouldn't get the total tandem power measurement that @Hovis is after though. I think.

How would you get drive to the rear wheel though?

Ah, you mean power at the cassette rather than power from both rider which can be added together?

Powertap is the answer- should last maybe four journeys before destroying itself I'd think.

The backwards p2m would be on the front, hooked up to the timing chain. Single ring on the inner ring position.

Anyways, just a thought experiment, never going to actually do it.

Also not sure if pedals would unscrew themselves.

Is there a spider or crank option that goes with Omniums?

Would it work in reverse and give us total tandem power?

If you want to measure total tandem power, you need to measure at the final drive, either the rear hub or the stoker's crank spider.

The difficult thing to measure in isolation is stoker power, you either have to measure at the stoker's pedals or use two PMs and subtract the driver's power from the total.

Is there a spider or crank option that goes with Omniums?

The lashed up option is to use a SRAM GXP Stages left crank, but it has all the usual problems associated with both Stages and single sided measurement and it makes your Q factor asymmetric.

Stages + SRAM S300 courier crankset should have a near identical Q-factor or the Quarq Dzero might work but no idea about chain lines.

I was being stupid. Thought the power from the stoker would come through the stoker chain and be measureable on the front. Silly me.

Ok cheers, good to cross that one off.