stroke rate /force curve errors

[meerkat]

My new model d is giving me stroke rate jumps up into the 70s on a regular basis . The force curve was jagged and when the stroke rate jumps to 70 the y value drops to zero for an instance before going back up and finishing the curve. I have the new pm5 fitted from new.
I tried a pm4 on my erg, the force curve was smoother but still dropped to zero before continuing and showed 70 strokes on these occasions.
I got a replacement coil under warranty -no change. Both pm4 and 5 had the errors but more in the PM5.
I tried my pm5 on another model d and it frequently jumped.
I got a replacement Pm5 - no change to irregular high stroke rates, but the force curve is smoother and the new pm5 v 19 is much more responsive in general .
I have cleaned the chain and the metal wheel thing that the coil senses -no change.


Any help greatly appreciated,

[jamesg]

That's what I get on my C-PM3. Had almost hoped its elimination would be a good reason to move to D-PM5, but if it's a bug evidently it has legs.
Can't we (or C2) just fit an industrial encoder and let us connect up to some Raspberry Pi or whatever?

[meerkat]

yes, I read your posts but figured thay must be different problems and all,what with your erg being older etc.
Your force curve looks a lot smoother than mine but my force curve is smoother on an older pm4 though. My force curve irregularities show the y axis value dropping to zero shortly after the catch. Then it carries on again. ..like it's saying I have done more strokes in that time.

[meerkat]

force cuve jump v3.jpg (22.74 KiB) Viewed 5224 times

This is what's happening on the pm4 and 5.