Power Meter on Sora

stevenmew
stevenmew Posts: 14
edited January 2017 in Workshop
Hi,

I'm pretty sure from everything I've read here and elsewhere that the answer to this is a yes but I would just like to see if anyone can give me a definitive answer from their own experience. I have the Btwin Triban 520 which has a Shimano Sora triple crankset and would like to invest in a power meter going forward. I believe that a crank arm based meter such as the stages or 4iiii on a 5800 Shimano 105 arm would work on my bike as they are both hollowtech ii systems. So assuming my bike has the necessary clearance to the frame, I could go ahead and buy one. Does this sound right? Is there anything I'm missing?

Thanks a lot. Also this is my first post but I have been reading through the forums for the last year and they've helped me countless times. A huge thanks to everyone here.

Comments

  • Should work fine as long as it clears the frame. Surely there's better things you could spend the money on though?
  • Bobbinogs
    Bobbinogs Posts: 4,841
    Yepp, it does beg the question "why on earth would you want to do that"?
  • StillGoing
    StillGoing Posts: 5,211
    I'd be thinking about changing the bike and groupset before contemplating buying a power meter. That's not to disparage BTwin, but why would you spend the equivalent of its value on a power meter? It simply doesn't make economic sense.
    I ride a bike. Doesn't make me green or a tree hugger. I drive a car too.
  • imposter2.0
    imposter2.0 Posts: 12,028
    Technically possible and there's no reason why you shouldn't do it. I don't get the comments about 'why?' because power is still power, regardless of what bike you are riding, or how much it costs.

    Buying a PM for your particular bike doesn't need justification in itself, but I would suggest that you need to be clear on why you want a PM in the first place - and what benefits you are expecting from it. And if you are clear on all that, then crack on.
  • OP's £, OP's choice. At least the power meter crank would be transferable to a new bike (or indeed any upgraded Hollowtech II crank set...)

    The only thing I'd say is take a look around the forums - here, Garmin, Road.cc - for people with issues between the latest Garmin head units (520,820,1000), various Garmin watches and Stages crank-based power meters - seems that placement of your head unit is critical to prevent dropouts in power data. Naturally Stages blame Garmin, Garmin blame Stages. All I can offer is my experience - Stages G2 (the "fixed" one), more dropouts than the 1960s; 4iiii no dropouts at all.

    Also there are persistent complaints of moisture ingress into the Stages causing battery drain in 24 elapsed hours & battery door failures.
  • slowbike
    slowbike Posts: 8,498
    Yes - the crank based power meter would work - given the correct clearance - I don't think there are any other options for a triple crankset - P2M don't do triple that I'm aware of.

    As for the sanity of adding a PM to what is a cheap bike - variety of reasons plausible - for use on a dumb turbo/rollers and winter training to name two ...
    Of course, nothing wrong with having a PM on a B'Twin - just try not to piss off your mates by rackng up some big power numbers then changing the bike for some racing machine and leaving them for dust! ;)
  • Alex99
    Alex99 Posts: 1,407
    Imposter wrote:
    Technically possible and there's no reason why you shouldn't do it. I don't get the comments about 'why?' because power is still power, regardless of what bike you are riding, or how much it costs.

    Buying a PM for your particular bike doesn't need justification in itself, but I would suggest that you need to be clear on why you want a PM in the first place - and what benefits you are expecting from it. And if you are clear on all that, then crack on.

    I agree with this. Sora works fine, and adding a power meter is a great way to do structured training and track your progress. It's a good move in my opinion. And, yes, a Stages will fit your Sora HTII chainset.

    Regarding other comments on cut outs etc... I now have two Stages PMs, both 5800 gen 2 units. They both have been reliable (a year, and a month respectively). I had problems with a gen 1 unit, but they swapped that for a gen 2 with no quibbles.
  • fenix
    fenix Posts: 5,437
    What about a powertap wheel ? You can take that between bikes too ?
  • Ok thanks for the replies.

    Regarding the economics of it, I know not everyone would want an expensive power meter on a cheap bike but I think it would be a worthwhile investment. I don't mind dropping the cash on something that's going to make me a better rider and then as I progress, earning my way to a better groupset and bike etc. Plus the missus would kill me if I attempt to buy a new bike but sneaking a new crank onto the existing one should go unnoticed!

    As to what power meter, it's basically the cheaper the better. The things are still very expensive and I'm only looking to get started with structured training and getting myself up to peak fitness. Therefore 'extras' such as left/right readings and accuracy to within a certain percentage don't bother me that much as long as the thing works. I live in Austria and can get the 4iiii for €380 at the moment. It strikes me as a good deal, accurate, not too many complaints about drops or waterproofing like the stages and can be transferred on to other bikes when the time comes. Anyone know or can suggest anything better than that? The powertap seems ok but for ease of fitting I'd probably go with a crank based solution. Also with brexit meaning brexit and the pound on its arse, if anyone knows of any UK based deals at the moment, I'll be back home in a week so could take advantage of that!
  • slowbike
    slowbike Posts: 8,498
    stevenmew wrote:
    Plus the missus would kill me if I attempt to buy a new bike but sneaking a new crank onto the existing one should go unnoticed!
    Excellent, love your thinking :)

    rather than buy a new bike - just buy new parts for the existing - keep the old parts and a second bike will slowly emerge :)
  • Alex99
    Alex99 Posts: 1,407
    Slowbike wrote:
    stevenmew wrote:
    Plus the missus would kill me if I attempt to buy a new bike but sneaking a new crank onto the existing one should go unnoticed!
    Excellent, love your thinking :)

    rather than buy a new bike - just buy new parts for the existing - keep the old parts and a second bike will slowly emerge :)

    There is an existential question here. At what point does it become a bike? When does the soul enter the bike? Presumable every component could become a bike so should we treat all single components as a complete bike? Is it wrong to stop building a bike once you've started?
  • slowbike
    slowbike Posts: 8,498
    Alex99 wrote:
    Slowbike wrote:
    stevenmew wrote:
    Plus the missus would kill me if I attempt to buy a new bike but sneaking a new crank onto the existing one should go unnoticed!
    Excellent, love your thinking :)

    rather than buy a new bike - just buy new parts for the existing - keep the old parts and a second bike will slowly emerge :)

    There is an existential question here. At what point does it become a bike? When does the soul enter the bike? Presumable every component could become a bike so should we treat all single components as a complete bike? Is it wrong to stop building a bike once you've started?
    I would think a part becomes a build when you join two components together without the sole intention of attaching them to an existing bike ...

    and in Trumps world - once you've started building that bike you should not abort the process ... :D
  • Alex99
    Alex99 Posts: 1,407
    Slowbike wrote:
    Alex99 wrote:
    Slowbike wrote:
    stevenmew wrote:
    Plus the missus would kill me if I attempt to buy a new bike but sneaking a new crank onto the existing one should go unnoticed!
    Excellent, love your thinking :)

    rather than buy a new bike - just buy new parts for the existing - keep the old parts and a second bike will slowly emerge :)

    There is an existential question here. At what point does it become a bike? When does the soul enter the bike? Presumable every component could become a bike so should we treat all single components as a complete bike? Is it wrong to stop building a bike once you've started?
    I would think a part becomes a build when you join two components together without the sole intention of attaching them to an existing bike ...

    and in Trumps world - once you've started building that bike you should not abort the process ... :D

    So it's only on the way to being a bike once it's a build. At this stage you should send blurry images of this to your friends and family saying "we have some news..."
  • slowbike
    slowbike Posts: 8,498
    Alex99 wrote:
    Slowbike wrote:
    Alex99 wrote:
    Slowbike wrote:
    stevenmew wrote:
    Plus the missus would kill me if I attempt to buy a new bike but sneaking a new crank onto the existing one should go unnoticed!
    Excellent, love your thinking :)

    rather than buy a new bike - just buy new parts for the existing - keep the old parts and a second bike will slowly emerge :)

    There is an existential question here. At what point does it become a bike? When does the soul enter the bike? Presumable every component could become a bike so should we treat all single components as a complete bike? Is it wrong to stop building a bike once you've started?
    I would think a part becomes a build when you join two components together without the sole intention of attaching them to an existing bike ...

    and in Trumps world - once you've started building that bike you should not abort the process ... :D

    So it's only on the way to being a bike once it's a build. At this stage you should send blurry images of this to your friends and family saying "we have some news..."

    Hmm ... that's got me thinking :D
  • slowbike
    slowbike Posts: 8,498
    actually - just recalled - it was similar to that how we broke the news of our impending arrival to my brothers ... 2 separate facetime calls went similar:

    Me: "I've got to get a new bike" ...
    Bro: "Haven't you got enough?"
    Me: "Nah - need one more, just a small one"
    at which point sister-in-laws got it and brothers just sat there with puzzled looks on their faces ... :)
  • dyrlac
    dyrlac Posts: 751
    Eh, I put a power meter on a charge plug 1 (a £200 special) that I had set up as a fixie. If you want power data, you want power data. It was my daily commuter and I was keeping an eye on my cumulative TSS.

    I second (third?) the point on Stages. Gen2 has a flaky antenna, I've returned 3 of them, until I finally replaced with a Pioneer left only version. The Pioneer module looks less well engineered (there's a visible gap along the edges of the sensor) than the stages, but has been solid, at least for left-only power (a separate debate entirely).

    I've also considered the issue of at what point is a bag of parts a new bike. When it was time to retire the Plug as the daily commuter, I bought an FXE frame in one of Dolan's clearances. Naturally a bare frame is classified as spare parts in the Dyrlac household inventory. Of course I took the parts from the plug (including the power meter), then needed to buy new (cheap!) parts to convert the plug into a shops/pub pootling singlespeed. Voila: two bikes out of nothing but "spare" parts. I also replaced just the frame and fork of my L'etape after a crash. New bike? I'd like to think not because I love that bike.
  • ridgerider
    ridgerider Posts: 2,851
    The only parts that haven't been changed on my first serious road bike, in the 15 years since I bought it, are the frame, front and rear hubs, handlebars and shifters. It's still the same bike though...
    Half man, Half bike