Hub based powermeter question

martyc5674

Ive not got a powermeter but thinking of stepping into the dark world..(or into the light?)

Ive had a look at prices and realistically the only affordable option to me right now is a second hand cycleops hub based unit.

I know the limitations regarding "one wheel" but im wondering if they calculate left/right power imbalance in anyway based on the position of your cadence meter?
Im guessing not and if that is the case then maybe a single sided pedal/crank unit might be just as good?

Cheers,
Marty.

Inquitus

martyc5674 wrote: »

Ive not got a powermeter but thinking of stepping into the dark world..(or into the light?)

Ive had a look at prices and realistically the only affordable option to me right now is a second hand cycleops hub based unit.

I know the limitations regarding "one wheel" but im wondering if they calculate left/right power imbalance in anyway based on the position of your cadence meter?
Im guessing not and if that is the case then maybe a single sided pedal/crank unit might be just as good?

Cheers,
Marty.

It doesn't give L/R balance, but it is measuring total power, not taking one side and doubling it.

martyc5674

Cheers yeah thats as i thought...surely be good enough for now.

Beasty

Not sure L:R balance really adds much (although I've a variety of PMs showing this and seem to have pretty similar power in each leg anyway) and Powertap have proven over the years to be a reliable option, subject to the issue of having to stick to the one wheel

fat bloke

Beasty wrote: »

Not sure L:R balance really adds much (although I've a variety of PMs showing this and seem to have pretty similar power in each leg anyway) and Powertap have proven over the years to be a reliable option, subject to the issue of having to stick to the one wheel

That's exactly it. That whole left & right argument. I have the two garmin pedals system. It consistently told me that my legs contribute 50/50 to the total output, so I don't need that metric anymore and have switched it off. So from now on I'd be as well off with the single pedal at half the price.

mossym

fat bloke wrote: »

That's exactly it. That whole left & right argument. I have the two garmin pedals system. It consistently told me that my legs contribute 50/50 to the total output, so I don't need that metric anymore and have switched it off. So from now on I'd be as well off with the single pedal at half the price.

if you are lucky enough to have 50/50 then you, as you say, can save a nice bit of cash with a one sided system. not my experience however, i've a dominant side, and worse, the %'s vary from easy up to >ftp efforts. probably points at an issue in my pedal stroke, but leaving that aside, means double sided measurements are a must for me, and likely others who see the same. i'd have no issues with a powertap though, it's still measuring both sides, not guessing at one

doozerie

One thing to factor into your decision of whether to buy a Powertap is the fact that the bearings in the hub will require replacement. How often that will be needed is debatable, anecdotes range from "rarely" to "quite often", my personal experience veers towards the latter.

If you have the bearings replaced by an approved agent of Powertap then the costs are significant - you have to factor in shipping costs too. If you replace them yourself then the costs are much less but decent quality steel bearings are not exactly cheap either - plus you void your warranty, and the drive side bearings are not easy to get at (certainly not on my SL+ anyway) so you may need to invest in the necessary tools too.