Stages Power Meter on a "dumb" trainer - why no speed/distance data?

Discuss light weight issues concerning road bikes & parts.
savechief
Posts: 317
Joined: Wed Aug 31, 2011 2:36 am

by savechief

Stages paired with Garmin Edge 520 on a Kurt Kinetic trainer. I am getting power and cadence, but no speed and distance. Am I fundamentally misunderstanding the limitation of the Stages? My usual power meter is a Powertap G3 hub, but it's out of commission due to a broken spoke. The Powertap, however, provides all four (power, cadence, speed, distance).
Time VXRS Ulteam (7.16 kg)
viewtopic.php?f=10&t=120268

User avatar
kkibbler
Posts: 840
Joined: Tue Sep 09, 2014 9:30 am

by kkibbler

Stages has no idea how fast your wheel is spinning, hence no speed, hence no distance.

by Weenie


savechief
Posts: 317
Joined: Wed Aug 31, 2011 2:36 am

by savechief

OK, so what options do I have? How do I record an indoor ride...by elapsed time only?
Time VXRS Ulteam (7.16 kg)
viewtopic.php?f=10&t=120268

Darceking
Posts: 131
Joined: Fri Feb 28, 2014 1:48 am

by Darceking

You need a speed sensor. Garmin make a good one

http://www.pushys.com.au/garmin-bike-sp ... AlwB8P8HAQ

savechief
Posts: 317
Joined: Wed Aug 31, 2011 2:36 am

by savechief

Thanks. Just ordered the Garmin speed sensor you posted. I have the old Garmin GSC 10 sensor, but like this solution better.
Time VXRS Ulteam (7.16 kg)
viewtopic.php?f=10&t=120268

eric01
Posts: 530
Joined: Mon Feb 06, 2006 1:06 am

by eric01

For completeness.... the Garmin 520 was giving you speed and distance based off of GPS signal. You're stationary indoors so... no GPS movement to detect.

Wheel sensor spin will give you speed and distance... but obviously under a stationary trainer conditions
AX Lightness Vial Evo, Carl Strong Titanium

joec
Posts: 100
Joined: Wed Mar 05, 2014 9:20 pm

by joec

do turn your Gps off on the garmin when using the trainer though

User avatar
ms6073
Posts: 2431
Joined: Fri Jul 23, 2004 8:24 pm
Location: Houston, Texas

by ms6073

WIth the Edge 520/820, if you select the 'Indoor' profile, the GPSis automatically disabled. For the OP, your results may differ, but I did not have good results when I tried the Garmin wireless speed sensor on the rear hub while riding on the trainer and opted to use the older style ANT+speed sensor mounted on the nds seat stay.
Michael - The Anaerobic Threshold is neither...

sungod
Posts: 1566
Joined: Fri Dec 24, 2010 9:37 pm
Location: it's raining, it must be uk

by sungod

if you're indoors bear in mind that "speed" and "distance" are wrong anyway, without air resistance the correlation to power is different

power are time are the only metrics i use on the turbo (plus cadence if doing some specific work on it), usually i'm training against an interval plan (which is power+time)

fwiw i've used that garmin hub sensor on the road for 7-8 months so far, it's been reliable, no issues after being soaked/baked/frozen

CrankAddictsRich
Posts: 1162
Joined: Wed Jan 27, 2016 1:39 pm
Contact:

by CrankAddictsRich

sungod wrote:if you're indoors bear in mind that "speed" and "distance" are wrong anyway, without air resistance the correlation to power is different


This makes no sense...
2016 Pactimo Brand Ambassador
http://www.Crankaddicts.cc
http://www.skratchlabs.com
2015 Specialized S-Works Allez
2015 Specialized Venge Pro
2014 Specialized S-Works Shiv TT

moonoi
Posts: 439
Joined: Sat Nov 21, 2015 3:04 pm

by moonoi

CrankAddictsRich wrote:
sungod wrote:if you're indoors bear in mind that "speed" and "distance" are wrong anyway, without air resistance the correlation to power is different


This makes no sense...


Indeed, the wheel spins and covers the same amount of "distance" for each rotation, regardless of wind resistance. The power meter is measuring power directly, so doesn't care what the wheel is doing, it's completely irrelevant.

If you were using a Powerpod, then that statement might make sense

gewichtweenie
Posts: 152
Joined: Fri Sep 25, 2015 3:12 pm

by gewichtweenie

moonoi wrote:
Indeed, the wheel spins and covers the same amount of "distance" for each rotation, regardless of wind resistance.

Unless the wheels slip either on road or trainer each rotation covers the exact same distance, all the time.

Smart trainers are calibrated to simulate resistance on flats and at grades.

Dumb trainers that are adjustable have unitless resistance control...So the same rev (or linear distance) covered at resistance 2 v 8 obviously requires completely different work ( energy). Meaning the apparent distance (or speed) read is.....Meaningless

...Unless it is hooked up to a computer system like zwift that translates resistance to known power curve.

moonoi
Posts: 439
Joined: Sat Nov 21, 2015 3:04 pm

by moonoi

Yes, that's what I said by saying the power meter doesn't care about the speed, it's completely irrelevant.

But I think that's what CrankAddictsRich was trying to say, albeit in a way that was poorly worded (along with my own poorly worded response), however your explanation brings clarity and that we're all saying the same thing.

savechief
Posts: 317
Joined: Wed Aug 31, 2011 2:36 am

by savechief

I ordered the new wireless Garmin speed sensor, but in the mean time I installed an old Garmin GSC 10 and magnet that I had laying around. So now I have speed and distance.

But I no longer have power and cadence due to the flakiness of connecting with my Stages. It connected (intermittently) last night, but now nothing. Edge 520 can't find it no matter what I do.

Sent from my SM-G930V using Tapatalk
Time VXRS Ulteam (7.16 kg)
viewtopic.php?f=10&t=120268

Darceking
Posts: 131
Joined: Fri Feb 28, 2014 1:48 am

by Darceking

Add the Stages manually. You can just put the ant+ code in, should find it. Make sure anything thats bluetooth is turned off also.

by Weenie


Post Reply
  • Similar Topics
    Replies
    Views
    Last post