Geoid PM500 power meter

[Icyseanfitz]

Any ideas on the best way to calibrate this? I can see a calibrate option on my old Garmin edge 800 but pressing it does nothing.

[jcr]

I use the calibrate on my Garmin (530) it seems to work. Bike stationary and upright. I have the crank at 6 and 12 o'clock.

Anyone tried the backpedal 5 times ?

[shaxberd]

Bought it to hopefully mount on a 1x GRX with a 46T Pass Quest chainring.
I now realized I don't know if I can add BB-spacers with this PM due to the crank interface (which I might need to to get the chainring away from the chainstay).
I have not clue if it's gonna work or not but we'll see. I'll report back.

Worst case I sell/gift it to a friend.

Did you end up getting that setup to work, especially considering the chain line? Used any spacers? I'm thinking about something similar (albeit with a smaller chainring) but the chain line difference to stock GRX seems quite drastic 🤔

[Tpower59]

Is this the real reliable cheap option ?

[ediryppah]

Did you end up getting that setup to work, especially considering the chain line? Used any spacers? I'm thinking about something similar (albeit with a smaller chainring) but the chain line difference to stock GRX seems quite drastic 🤔

Yeah it worked to install it with a spacer (don’t remember if it was 1, 2 or 3 mm) but the power was kind of off. Removed it (the 46T still had clearance, just a bit tight) and power accuracy was better.

Honestly though I’m not sure it was due to the spacer or me just quickly assembling everything (wrong torques and stuff) or if I even calibrated before the test. I’m often doing some chaos work and don’t stop and think.

So all in all, yes it worked to install with spacer but I’m not using a spacer currently.

[Gloopann]

Is this the real reliable cheap option ?

I would also like to know, as I really want a powermeter soon and this seems promising. Definitely seems like it to so far, at least from what I've gathered from the forum. Other cheap PMs like the Coospo and the Thinkrider seem to have false readings, and the general recommendation was the PES 505 or the 515, and this seems to be the same powermeter, just repackaged and about 30% cheaper than those.

[shaxberd]

I’m often doing some chaos work and don’t stop and think.

Hah, that sounds like a bit of me tbh.

Are all your gears rideable as well, or are any of them particularly loud or something due to the chain line difference?

[ediryppah]

Hah, that sounds like a bit of me tbh.

Are all your gears rideable as well, or are any of them particularly loud or something due to the chain line difference?

The 51T and to some extent 45T was always kind of shit honestly, but I rarely use it anyway. If anything it should be better now with a tighter chainline. The GRX chainline is way too wide but makes sense for frame clearance I guess.

The "normal" parts of the cassette (let's say 10 to 39) is flawless.

[jlut]

FYI

Difference between Geoid 500 Crankset and Magene PES505 Crankset

1. The Senicx PR3 crankarms are slightly more outwards curved, while the Magene PES505 are straight and run diagonal between spindle and pedal eye. I always had issue running a 105 Di2 or GRX 12s Di2 FD, because it was rubbing against the driveside Magene arm in the bigring and high gears. Only solve was to use an Ultegra Di2 FD. With the Senicx there is way more room.

2. The Senicx PR3 Crankset that comes with the Geoid 500 has about 3mm shorter chainline than the Magene PES505! I now have the issue that my 34 inner ring is only 1 mm away from the chainstay. With the Magene arms I has about 4 mm of space to the frame.

Tomorrow I'll try to see if the Geoid Spider has a different chainline from the PES505. But I suspect not.

Do you know if it is possible to change the crank length of my PES505 by buying some Senicx PR3/PR4 cranks?

[lorenzo]

Do you know if it is possible to change the crank length of my PES505 by buying some Senicx PR3/PR4 cranks?

They have a different interface, so they won’t fit. If you contact Magene via email, you can order just the PES cranks. I bought a set a while ago; I think it was around $70 shipped.

[HerbnLegend]

Hey chat just wanted to share my experience so far with the PM500. Installed it a few weeks ago. Swapped out my 105Di2 crankset and it works flawlessly. I'm using the stock shimano 105 chainrings and they fit and shift perfectly. The big ring is not flush with the crank, not even close, but I don't care about looks/aero whatever, just function. Paired it to my Garmin watch and edge, calibrated via edge - seems to be accurate. I have about 200mi on it so far and it's been a joy. No complaints! I haven't tried to connect to the Magene app, just learned of that while reading through this thread. Cheers!
edit: forgot to mention, I picked it up on amazon for $171.71USD shipped. Absolute bargain for this thing.

[Rufusz]

Anyone using the PM500 in 1x setup?
Looking to install it to T47 85.5mm frame, not sure if fits...

[oxidizer]

Anyone using the PM500 in 1x setup?
Looking to install it to T47 85.5mm frame, not sure if fits...

Yes. 50t chainring from goldix.

[ediryppah]

Anyone using the PM500 in 1x setup?
Looking to install it to T47 85.5mm frame, not sure if fits...

Yeah on my gravel bike. 46T chainring

[geramonta]

Any ideas on the best way to calibrate this? I can see a calibrate option on my old Garmin edge 800 but pressing it does nothing.

I'm having the same issue with the Coros Dura. I press "Calibrate," but it never completes the calibration and eventually returns an error. I also can't calibrate it through the Magene app, and it's reporting lower power values than expected. It's off by about 40-60 watts.

Since I installed it about a week ago, I haven't been able to calibrate it successfully. Does anyone know of another app that can be used for calibration?

I've spun the cranks backward five times, and the readings remain the same, so it might be a defective unit. I've compared it against two other power meters and a smart trainer, and they all show very similar values, except for this one.