Advertise on Bikeforums.net



User Tag List

Results 1 to 25 of 25
  1. #1
    Dharma Dog lhbernhardt's Avatar
    Join Date
    Mar 2006
    Location
    Vancouver, Canada
    My Bikes
    Rodriguez Shiftless street fixie with S&S couplers, Kuwahara tandem, Trek carbon, Dolan track
    Posts
    2,065
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Crank-Mounted Power Meter

    Any of you experts here have any recommendations? I'm looking for a crank-based power meter for use on the track, since I don't want to be tied to using just one wheel (I realize the easy solution for track is a hub-based power meter like a PowerTap, but even that would require a bit of tweaking). And SRM is too expensive to be in the equation.

    Ideally, the unit would work with a Shimano external bb, as this has the best method of crank attachment (I've used SRAM with the Omnium, and it leaves a lot to be desired). But then I'd have to switch to 130mm bcd rings, but Gebhardt makes 1/8" track chainrings in al sizes. The solution I'm looking at now is a Power2max on 165mm Rotor 3D cranks, but I'm concerned about the chainline. I want to be able to use a standard track rear hub, and all the crank-based power meters I've seen assume you're using road stuff.

    Anyone here have any experience or recommendations? Thanks.

    Luis

  2. #2
    Senior Member
    Join Date
    Jan 2006
    Location
    Australia
    Posts
    1,461
    Mentioned
    5 Post(s)
    Tagged
    0 Thread(s)
    I've read (either here or fixedgearfever) that some have used Quarq's. Either 130 bcd or using a custom made adapter plate on a 110 bcd crank that allows them to use 144 bcd chain rings... Haven't heard of anyone using a Power2max.

    Perhaps try posting the question on the wattage google group?
    http://climbinglama.blogspot.com.au

  3. #3
    Elitist carleton's Avatar
    Join Date
    Jul 2005
    Location
    Atlanta, GA
    Posts
    11,039
    Mentioned
    6 Post(s)
    Tagged
    1 Thread(s)
    SRM is pretty much it.

    Look for used sets. You can replace the crank arms for $200 if the used set doesn't have the length you need.

    It's not a perfect system (no user-replaceable batteries)...but it's the best available now for track.

  4. #4
    Senior Member Kayce's Avatar
    Join Date
    Aug 2010
    Location
    St Louis
    Posts
    1,846
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    A few years ago at NAHBBS I saw a pedal based power system. I have no idea who was working on it or if anything came out of it, but maybe look into that.
    If You Meet The Buddha On The Road, Kill Him

  5. #5
    Morton Nagrom_'s Avatar
    Join Date
    Dec 2011
    Location
    East Bay
    My Bikes
    Kilo TT, CAAD10
    Posts
    9,704
    Mentioned
    4 Post(s)
    Tagged
    0 Thread(s)
    It was LOOK iirc.
    Quote Originally Posted by seau grateau View Post
    No offense but you're an idiot.
    PedalRoom

  6. #6
    A little North of Hell
    Join Date
    Mar 2006
    Posts
    4,365
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    pedal power meter

    http://sites.garmin.com/vector/#power

    there is more than one system...
    [SIGPIC][/SIGPIC]
    XXXI

  7. #7
    Morton Nagrom_'s Avatar
    Join Date
    Dec 2011
    Location
    East Bay
    My Bikes
    Kilo TT, CAAD10
    Posts
    9,704
    Mentioned
    4 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by seau grateau View Post
    No offense but you're an idiot.
    PedalRoom

  8. #8
    Senior Member
    Join Date
    Jan 2006
    Location
    Australia
    Posts
    1,461
    Mentioned
    5 Post(s)
    Tagged
    0 Thread(s)
    The issue with pedal based PM's is the fact only one actually exists (the Look pedals) and even that has been a very limited release with a number of issues. The Vector has had the release date pushed back for at least a couple of years now...

    There are quite a few groups trying to measure power at the pedal and only the Look has made it to market. Others include Brim Brothers cleat system http://www.brimbrothers.com/ and an Australian system http://www.bikepowerpedals.com/ but with no photos that I've only just heard about.

    For crank options, it may be worthwhile considering the Stage One model with a couple of caveats - only very new so you would be a beta tester, plus it only measures one leg and just assumes you are balanced. They do have a 7710 crank arm available in their range - at this time they can't be fitted to carbon arms http://www.stagescycling.com/stageone-models

    Personally I'd looked for a second hand wired SRM. I have three wired SRM's (SRM Pro on the road bike, FSA SRM on the TT bike and SRM track swapped between my training and race track bikes). They were all bought second hand and all working flawlessly.
    http://climbinglama.blogspot.com.au

  9. #9
    Elitist carleton's Avatar
    Join Date
    Jul 2005
    Location
    Atlanta, GA
    Posts
    11,039
    Mentioned
    6 Post(s)
    Tagged
    1 Thread(s)
    There are LOTS of proposed power meter systems out there because the Triathletes will buy them. They have lots of money. Most of which never make it to market. Of the ones that DO actually make it to market, only one is made for track...SRM.

    PowerTap does some funky interpolation of the data as it actually samples at over 1 per second.

    The pedal systems can't make it out of testing.

    You guys can listen to the marketing speak and hold out and wait for the pedal/shoe based systems if you want. But, if it's taking this long for them to make it to market, you'd best believe that the first generation that does will be very buggy.

    SRM has been around for a LONG time. If you need a power meter now (not 2 or more years from now) find one.

    On the other hand, power meters aren't really necessary. A computer that tracks speed and cadence data for download and analysis will do 95% of what you'd use a power meter for. I've had an SRM for 3 full seasons and I evaluate Speed and Cadence data waaaaay more than power.

  10. #10
    aka mattio queerpunk's Avatar
    Join Date
    May 2005
    Posts
    5,418
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Dalai View Post
    I've read (either here or fixedgearfever) that some have used Quarq's. Either 130 bcd or using a custom made adapter plate on a 110 bcd crank that allows them to use 144 bcd chain rings... Haven't heard of anyone using a Power2max.

    Perhaps try posting the question on the wattage google group?
    A friend of mine is the one who makes the 110->144 adaptor plates for Quarq. They work really well and even with the cost of the plate+Quarq, comes out cheaper than a track SRM.

    Here's FGF chatter about it:
    http://www.fixedgearfever.com/module...er=asc&start=0
    the hipster myth.

    i practice vagabondery.

  11. #11
    Morton Nagrom_'s Avatar
    Join Date
    Dec 2011
    Location
    East Bay
    My Bikes
    Kilo TT, CAAD10
    Posts
    9,704
    Mentioned
    4 Post(s)
    Tagged
    0 Thread(s)
    Found something in the 41 and remembered this thread.

    http://www.dcrainmaker.com/2012/11/1...wer-meter.html

    http://www.bikeforums.net/showthread...ter-(with-pics!)


    Might be a solution?
    Quote Originally Posted by seau grateau View Post
    No offense but you're an idiot.
    PedalRoom

  12. #12
    Elitist carleton's Avatar
    Join Date
    Jul 2005
    Location
    Atlanta, GA
    Posts
    11,039
    Mentioned
    6 Post(s)
    Tagged
    1 Thread(s)
    Quote Originally Posted by Nagrom_ View Post
    Found something in the 41 and remembered this thread.

    http://www.dcrainmaker.com/2012/11/1...wer-meter.html

    http://www.bikeforums.net/showthread...ter-(with-pics!)


    Might be a solution?
    The best paragraph in his review:

    Many folks ask if they should ‘wait’ for the Zone – or the Vector, or the Rotor, or any other fill in the blank power meter. And my answer is largely the same each time. If you need a power meter today, go out and get a power meter today. If you feel like you can wait – then consider waiting. In general, I think we’ll see far more units on the market this spring, than we have on shelves today. But that also means many more months of waiting and lost time training with a power meter. And, the same will be true in the spring, when we look towards the fall and find yet another batch of units either being readied or prepared for announcement at the likes of Eurobike and Interbike.
    There are so many that are proposed...that will never be anything but prototypes.

  13. #13
    Morton Nagrom_'s Avatar
    Join Date
    Dec 2011
    Location
    East Bay
    My Bikes
    Kilo TT, CAAD10
    Posts
    9,704
    Mentioned
    4 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by carleton View Post
    There are so many that are proposed...that will never be anything but prototypes.
    Absolutely. All of these other solutions have been in the works for quite a while too, and have yet to catch on. Says something.

    Also just noticed the one I just linked only works for speedplay pedals, which don't seem to be very popular on the track.
    Quote Originally Posted by seau grateau View Post
    No offense but you're an idiot.
    PedalRoom

  14. #14
    Elitist carleton's Avatar
    Join Date
    Jul 2005
    Location
    Atlanta, GA
    Posts
    11,039
    Mentioned
    6 Post(s)
    Tagged
    1 Thread(s)
    Quote Originally Posted by Nagrom_ View Post
    Absolutely. All of these other solutions have been in the works for quite a while too, and have yet to catch on. Says something.

    Also just noticed the one I just linked only works for speedplay pedals, which don't seem to be very popular on the track.
    The one you linked to does not exist as a finished product It's only a prototype. There may only be a handful in existence.
    Last edited by carleton; 11-28-12 at 05:50 PM.

  15. #15
    Senior Member
    Join Date
    Aug 2006
    Location
    Huntersville, NC
    My Bikes
    yes!
    Posts
    192
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Just to bring this back up as I saw this in one of my mountain bike mags. I know SRM is the ticket, but just to add something else to the mix... http://store.nexternal.com/stages/st...-track-p9.aspx
    Tiemeyer For Sale
    http://s228.photobucket.com/user/cowboy600rr/library/Tiemeyer%20For%20Sale

  16. #16
    Elitist carleton's Avatar
    Join Date
    Jul 2005
    Location
    Atlanta, GA
    Posts
    11,039
    Mentioned
    6 Post(s)
    Tagged
    1 Thread(s)
    Quote Originally Posted by Pantani98 View Post
    Just to bring this back up as I saw this in one of my mountain bike mags. I know SRM is the ticket, but just to add something else to the mix... http://store.nexternal.com/stages/st...-track-p9.aspx
    Wow. That's interesting. I'd heard of it before, but I didn't know they had a track version.

    My ONLY gripe is that it only records from one leg and interpolates (guesses) what the other leg is doing. I'm not sure if I'd use it for sprint work. Maybe TTs it would be OK.

  17. #17
    Morton Nagrom_'s Avatar
    Join Date
    Dec 2011
    Location
    East Bay
    My Bikes
    Kilo TT, CAAD10
    Posts
    9,704
    Mentioned
    4 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by carleton View Post
    Wow. That's interesting. I'd heard of it before, but I didn't know they had a track version.

    My ONLY gripe is that it only records from one leg and interpolates (guesses) what the other leg is doing. I'm not sure if I'd use it for sprint work. Maybe TTs it would be OK.
    Also only goes up to 2k watts. I doubt it will be an issue for many, but i'm sure someone who can break that would be a little disappointed to see their power graph plateau.

    The price isn't too bad though.
    Quote Originally Posted by seau grateau View Post
    No offense but you're an idiot.
    PedalRoom

  18. #18
    Senior Member
    Join Date
    Jan 2006
    Location
    Australia
    Posts
    1,461
    Mentioned
    5 Post(s)
    Tagged
    0 Thread(s)
    I mentioned all the above (Stages / Brim Brothers) on the 16th...
    http://climbinglama.blogspot.com.au

  19. #19
    Senior Member
    Join Date
    Aug 2006
    Location
    Huntersville, NC
    My Bikes
    yes!
    Posts
    192
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Dalai View Post
    I mentioned all the above (Stages / Brim Brothers) on the 16th...
    Doh! Yes you did. That will teach me to speed read (scan). I just wanted to mention it again in case anyone (me) missed it. Haha!!!
    Tiemeyer For Sale
    http://s228.photobucket.com/user/cowboy600rr/library/Tiemeyer%20For%20Sale

  20. #20
    Morton Nagrom_'s Avatar
    Join Date
    Dec 2011
    Location
    East Bay
    My Bikes
    Kilo TT, CAAD10
    Posts
    9,704
    Mentioned
    4 Post(s)
    Tagged
    0 Thread(s)
    Hey guys, stumbled upon a 110-144BCD converter while browsing for other things, and remembered this thread yet again. This seems much more readily available than the custom made one mentioned here.
    http://www.bdopcycling.com/Track%20P...p#TRACKADAPTOR
    Quote Originally Posted by seau grateau View Post
    No offense but you're an idiot.
    PedalRoom

  21. #21
    VeloSIRraptor
    Join Date
    Mar 2008
    Location
    Seattle, WA
    Posts
    4,318
    Mentioned
    3 Post(s)
    Tagged
    0 Thread(s)
    BDop is good people - and he says he has a 130-144 adaptor drawn up that he says he hopes to have available (as in, buyable and usable, in the flesh) in the near-ish future.
    Quote Originally Posted by shovelhd View Post
    If it comes down to a field sprint, you probably won't win, so don't let it.

  22. #22
    Morton Nagrom_'s Avatar
    Join Date
    Dec 2011
    Location
    East Bay
    My Bikes
    Kilo TT, CAAD10
    Posts
    9,704
    Mentioned
    4 Post(s)
    Tagged
    0 Thread(s)
    BDop is great people. Sells great products for great prices and has the fastest shipping from Taiwan I've ever seen.
    Quote Originally Posted by seau grateau View Post
    No offense but you're an idiot.
    PedalRoom

  23. #23
    Elitist carleton's Avatar
    Join Date
    Jul 2005
    Location
    Atlanta, GA
    Posts
    11,039
    Mentioned
    6 Post(s)
    Tagged
    1 Thread(s)
    Quote Originally Posted by Hida Yanra View Post
    BDop is good people - and he says he has a 130-144 adaptor drawn up that he says he hopes to have available (as in, buyable and usable, in the flesh) in the near-ish future.
    Quote Originally Posted by Nagrom_ View Post
    BDop is great people. Sells great products for great prices and has the fastest shipping from Taiwan I've ever seen.
    +1

    He's also a bikeforums member. He's active on the Road and Road Racing forums.

    http://www.bikeforums.net/member.php/87367-Bob-Dopolina

    His blog: http://oldguyracer.blogspot.com/

  24. #24
    Resident Alien Racer Ex's Avatar
    Join Date
    Jul 2007
    Location
    Let me check.
    My Bikes
    Of course.
    Posts
    11,287
    Mentioned
    16 Post(s)
    Tagged
    1 Thread(s)
    I run a Rotor 3D+ BB30 SRM with 130 BCD Miche 1/8 track rings; I set it up with a shaved down small ring with the chain rings nuts epoxied in; very quick and easy ring changes. Rotor makes a "plug and play" EXO threaded bottom bracket that will allow BB30 for some units in a standard BB shell.

    Unless you're a Chris Hoy 2000w guy you're not going to have an issue at 130 vs. 144 with flex, especially if you go BB30, so road SRM's are an option without an adapter. You probably won't be able to borrow rings at the track though. 1/8" 130 BCD rings are out there from cheap (Vuelta) to a bit pricey (Miche, but they weren't that bad through Ribble int he UK and they are really well made).

    Only certain road SRM's will work for this application, contingent on the meter/crank interface (7800/7900 Dura Ace for instance are "no go"). And only a few come available with 165 arms.

    Quarq is a very poor solution; they recommend calibration when changing rings and I'd be very leery with the back pressure sending those units into a tizzy. I think around 90% of the folks I know have had to send units back, some as many as four.

    The pedal stuff is vaporware other than Look, and they have more than a few teething problems and customer support problems.

    Stages is cataloging a Dura Ace track model. Which means a big "maybe". They have zero of anything purchasable right now, the road units that are out there are beta and buggy and I would guess that their production focus is going to be on what they have the most pre-order's on. That said if they do get it up and running, and reliable, it would be the cheap alternative to SRM.

    But that's a lot of ifs.
    Last edited by Racer Ex; 04-05-13 at 01:15 AM.

  25. #25
    Senior Member
    Join Date
    Jan 2006
    Location
    Australia
    Posts
    1,461
    Mentioned
    5 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Racer Ex View Post
    Unless you're a Chris Hoy 2000w guy you're not going to have an issue at 130 vs. 144 with flex, especially if you go BB30, so road SRM's are an option without an adapter. You probably won't be able to borrow rings at the track though. 1/8" 130 BCD rings are out there from cheap (Vuelta) to a bit pricey (Miche, but they weren't that bad through Ribble int he UK and they are really well made).

    Only certain road SRM's will work for this application, contingent on the meter/crank interface (7800/7900 Dura Ace for instance are "no go"). And only a few come available with 165 arms.
    I've read road SRM Professional cranks always don't like being used fixed - can't recall exactly why though.

    Track SRM's do come up for sale infrequently. I bought mine on fleabay - thankfully many times when marked as for sale in the US only people will send OS if asked.
    http://climbinglama.blogspot.com.au

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •