My Model C was retrofitted with a PM3 several years ago. Sometime over the past year, I noticed its readouts had become increasingly erratic. I've got firmware v.108 on the PM3.
I first noticed problems in the 500K split "speed" readout. The rate would jump by 14 or 15 seconds (always toward an erroneously faster speed), hang there for a second and then return to the correct rate. The longer the session, the shorter the intervals between excursions seems to become.
I'm now noticing a fluctuation in my stroke rate. Wild swings -- say from my usual 22-23 up to the 90's for a short period.
I know there have been threads on these bugs in earlier posts, but a quick scan today suggests not many are experiencing these problems with the PM3. I keep my erg chain oiled, cage cleaned out periodically, and while it has years, it's only got 7.2 million meters on it. Any fixes I've missed?
What's going on with my PM3?
What's going on with my PM3?
79 yrs. old; inactive for about five years; trying to re-start! 8 million meter club.
Re: What's going on with my PM3?
Seen the same, replaced the sensor and cable. This had some effect but not 100% cured. If you look at the force curve, when the curve is smooth there's no problem; but if it's irregular with missing data points, there'll be a peak in the bar diagram and odd readings for pace, W and rate. The irregularities always appear in the second half of the stroke, when the curve is dipping anyway.
My guess is the PM3 reads max and minimum flywheel speeds by counting impulses, and if there's a hole in the impulse train, it sees this as a minimum speed and calculates as if we've pulled two strokes rather than one.
Could be a dodgy connection in the PM3 (unlikely), or maybe my magnets are getting weaker after ten years, along with the rest of me, or there is some extra play between sensor/frame and flywheel. The gap is a few mm, so a touch of a hammer on the frame to move the sensor closer could be just what's needed.
My guess is the PM3 reads max and minimum flywheel speeds by counting impulses, and if there's a hole in the impulse train, it sees this as a minimum speed and calculates as if we've pulled two strokes rather than one.
Could be a dodgy connection in the PM3 (unlikely), or maybe my magnets are getting weaker after ten years, along with the rest of me, or there is some extra play between sensor/frame and flywheel. The gap is a few mm, so a touch of a hammer on the frame to move the sensor closer could be just what's needed.
08-1940, 179cm, 75kg post-op (3 bp January 2025).
- Citroen
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Re: What's going on with my PM3?
Check the continuity on the sensor cable. it's easy to tear those small wires.
Check the flywheel has all the magnets in place.
Check the flywheel has all the magnets in place.
- Carl Watts
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Re: What's going on with my PM3?
Go back to V105 and you will not have the problem.
For some reason V108 can have 2 to 3 single strokes in a 30minute that suddenly change to something way out both faster in pace and rating. When I fist saw it I thought I was seeing things.
It also effects only certain Hardware versions of PM3 and not others.
If it really annoys you then get Concept 2 to send you the V105 file and you simply drag this onto the update utility and it will take you back to V105 where I have never seen the problem occur.
For some reason V108 can have 2 to 3 single strokes in a 30minute that suddenly change to something way out both faster in pace and rating. When I fist saw it I thought I was seeing things.
It also effects only certain Hardware versions of PM3 and not others.
If it really annoys you then get Concept 2 to send you the V105 file and you simply drag this onto the update utility and it will take you back to V105 where I have never seen the problem occur.
Carl Watts.
Age:58 Weight: 104kg Height:183cm
Concept 2 Monitor Service Technician & indoor rower.
http://log.concept2.com/profile/863525/log
Age:58 Weight: 104kg Height:183cm
Concept 2 Monitor Service Technician & indoor rower.
http://log.concept2.com/profile/863525/log
Re: What's going on with my PM3?
Thanks to jamesg, Citroen, and Carl Watts for your responses.
This reply has been delayed by cataract surgery which beached my erg-ing for a few weeks.
After helpful comments from each of you -- much appreciated ones -- I tried cleaning off the sensor surface as well as the magnet heads. Pushed the sensor as far into the action as I could and also gave as close an inspection as possible of the wiring. Nothing eliminated the problem.
Then I spoke with Josh Carlson of C2's support staff. He was very helpful and echoed your troubleshooting advice. I ended up ordering the replacement part (PN 1748) and installed it. It's almost a certainty that the wire had problems. It had been around for 16 years and, well, some things do deteriorate as we get older. Not a daunting repair (the smaller one's hands the better), but it took a while to figure out how to extract the Tuflok screw.
Pleased to report the excursions seem to be a thing of the past. Quite a relief. And, I'm back at the "oars."
Thanks again.
Terry
This reply has been delayed by cataract surgery which beached my erg-ing for a few weeks.
After helpful comments from each of you -- much appreciated ones -- I tried cleaning off the sensor surface as well as the magnet heads. Pushed the sensor as far into the action as I could and also gave as close an inspection as possible of the wiring. Nothing eliminated the problem.
Then I spoke with Josh Carlson of C2's support staff. He was very helpful and echoed your troubleshooting advice. I ended up ordering the replacement part (PN 1748) and installed it. It's almost a certainty that the wire had problems. It had been around for 16 years and, well, some things do deteriorate as we get older. Not a daunting repair (the smaller one's hands the better), but it took a while to figure out how to extract the Tuflok screw.
Pleased to report the excursions seem to be a thing of the past. Quite a relief. And, I'm back at the "oars."
Thanks again.
Terry
79 yrs. old; inactive for about five years; trying to re-start! 8 million meter club.