Geoid PM500 power meter

[hubba]

Anyone installed the GEOID PM500 on a GRX 2by and got it working considering the chainline / FD?

Which affordable 46/30 110BCD chainrings did you use?

You can't fit a 30t chainring on 110bcd bolt spacing. Smallest one that fits is a 33t unless you use oval chainrings. GRX uses 110bcd on the large and 80bcd on the small ring.

[zealot128]

Some update on my broken PM unit:

I had some contact back-and-forth via E-Mail (and Aliexpress Chat, to escalate more quickly) and had to make some videos "Please calibrate again" "Please calibrate again using a different device" etc.
After that, they agreed to send me a new unit, if a pay the delivery of about $10, which I did. (I should order another $10 item from their Aliexpress +3 EUR tax and instead the new PM arrived).
I only needed a new spider, but maybe their SKU system does not allow for that, so now, I have 2 alu cranksets 🤷🏻. But the new PM works again, lets see for how long!

One thing though: After installing it back together with the Shimano 105 chainrings (as my Passquest are on another crankset for testing carbon stuff), it is now squeaking like hell after 2 rides. I didn't invest too much time to find the exact issue for now (chainring bolts torqued), but instead I swapped to a newer carbon crank PM - the squeaking is gone, so it is indeed the combo of geoid/their alu crankset/shimano105-chainring together in my BB making the noises.

[maxpet]

Some update on my broken PM unit:

I had some contact back-and-forth via E-Mail (and Aliexpress Chat, to escalate more quickly) and had to make some videos "Please calibrate again" "Please calibrate again using a different device" etc.
After that, they agreed to send me a new unit, if a pay the delivery of about $10, which I did. (I should order another $10 item from their Aliexpress +3 EUR tax and instead the new PM arrived).
I only needed a new spider, but maybe their SKU system does not allow for that, so now, I have 2 alu cranksets 🤷🏻. But the new PM works again, lets see for how long!

One thing though: After installing it back together with the Shimano 105 chainrings (as my Passquest are on another crankset for testing carbon stuff), it is now squeaking like hell after 2 rides. I didn't invest too much time to find the exact issue for now (chainring bolts torqued), but instead I swapped to a newer carbon crank PM - the squeaking is gone, so it is indeed the combo of geoid/their alu crankset/shimano105-chainring together in my BB making the noises.

My brother has this exact setup on his bike with zero issues / creaking

[GLTRV]

I tested the PM500 against my Tacx Neo 2T a while ago and posted the results on Reddit and wanted to post the results here as well but had trouble logging in. Anyway, now that I've managed to log in, here are the results.

I installed a Geoid PM500 on my gravel bike thinking (hoping) it would offer the performance of the now discontinued Magene P505 at a lower price as the Magene is well proven and I'm happy with mine on my road bike.
However, I have not seen much testing of the PM500, so I decided to do a quick and dirty test of mine against my Tacx Neo 2T by comparing the two fit files using compare-the-watts.com

Results (with 2 seconds offset and 1second smoothing):

Overall


Some low power steps in ERG mode (the slope is the Neo 2T not adjusting resistance fast enough to compensate for me raising the cadence)


Higher power steps in ERG mode


1st 1000+ watt effort in free ride mode


2nd 1000+ watt effort in free ride mode


3rd 1000+ watt effort in free ride mode


 Observations regarding the PM500:
- Tracks the Neo 2T pretty well overall.
- No fumble after 1000+ watt efforts (seems to be the pitfall of many power meters tested by Mr. Lama, including the latest crop of affordable models, unfortunately).
- Seems to be more responsive to sudden power increases (always felt the Neo 2T felt "smoothed" compared to my P505 ridden outside).
- Several drops in cadence can be seen, but I don't know if it's some sort of glitch, connection issue or the meter picking up drops in my not very smooth pedaling (linked to previous point?), but there doesn't seem to be any corresponding drops in power, weird.
- There is a drop in power between the 28th and 30th seconds in the 3rd 1000+ watt effort, but no cadence drop, again, weird (linked with the 2 previous points?).

I'm happy with the results, it's close enough to the Neo 2T and doesn't exhibit offset problems after higher power efforts.

Installation is very straightforward, just like a Shimano crank, simpler than the Magene PES P505.
The most negative point about this power meter (and other Magene spider power meters) is the crank interface, I wish it were Easton compatible.

I hope this post was of interest to those shopping for affordable power meters

[zett]

How is clearance with 86.5 mm T47 bottom bracket shells with this PM? Considering it for a cheap powermeter upgrade for my gravel bike (which would also get rid of my shitty GXP crankset).

[Dan S.]

How is clearance with 86.5 mm T47 bottom bracket shells with this PM? Considering it for a cheap powermeter upgrade for my gravel bike (which would also get rid of my shitty GXP crankset).

I would say as this is basically a PES P505 Base, it will very much depend on the shape of your BB area. T47 was not supported by default, but if the shape is favourable, it might fit.

[Lotnik]

How is clearance with 86.5 mm T47 bottom bracket shells with this PM? Considering it for a cheap powermeter upgrade for my gravel bike (which would also get rid of my shitty GXP crankset).

In the thread there are some feedbacks that it fits wit T47.

[frenzen]

will this fit with bb89?

[BFBS]

Which chainrings are compatible with the Powermeter and a 2x10 Tiagra?
I want to switch to 165mm cranks anyways and the Powermeter is just a bit more expensive than those.

[ediryppah]

Which chainrings are compatible with the Powermeter and a 2x10 Tiagra?
I want to switch to 165mm cranks anyways and the Powermeter is just a bit more expensive than those.

If they’re 4 bolt 110mmBCD I guess just re-use the ones you have.

[kbernstein]

Some update on my broken PM unit:

I had some contact back-and-forth via E-Mail (and Aliexpress Chat, to escalate more quickly) and had to make some videos "Please calibrate again" "Please calibrate again using a different device" etc.
After that, they agreed to send me a new unit, if a pay the delivery of about $10, which I did. (I should order another $10 item from their Aliexpress +3 EUR tax and instead the new PM arrived).
I only needed a new spider, but maybe their SKU system does not allow for that, so now, I have 2 alu cranksets 🤷🏻. But the new PM works again, lets see for how long!

One thing though: After installing it back together with the Shimano 105 chainrings (as my Passquest are on another crankset for testing carbon stuff), it is now squeaking like hell after 2 rides. I didn't invest too much time to find the exact issue for now (chainring bolts torqued), but instead I swapped to a newer carbon crank PM - the squeaking is gone, so it is indeed the combo of geoid/their alu crankset/shimano105-chainring together in my BB making the noises.

I had some massive squeaking on tiagra 4700 chainrings. I replaced them thinking it would stop (it was pretty close to toast too anyway) with ultegra r8100, lithium grease on the bolts and torqued to 14nm each and it still squeaks like crazy. Was I supposed to grease the plastic/aluminium interface too? Did you get it fixed?

[Rajmundx]

Where do you set it up on this power meter so that the bike computer also reads cadence? I have a Wahoo ELEMNT BOLT 2, and it only shows power, while cadence is picked up from a Magene sensor.

[GLTRV]

Where do you set it up on this power meter so that the bike computer also reads cadence? I have a Wahoo ELEMNT BOLT 2, and it only shows power, while cadence is picked up from a Magene sensor.

You don't need the cadence sensor, ditch it. Your computer should read cadence from the power meter if there is no other cadence sensor connected.

[Rajmundx]

You don't need the cadence sensor, ditch it. Your computer should read cadence from the power meter if there is no other cadence sensor connected.

Thank you I will check.

[johnnyboy4711]

take a punt on this for a road training bike?