The GEOID PM500 is a budget-friendly spider-based power meter offering good value, but with mixed accuracy reports and potential reliability concerns.
Pros
- Very affordable, often 2/3 the price of similar Magene models
- Easy to install, similar to Shimano cranks
- Provides left/right power readings
- Compatible with major cycling computers via ANT+/Bluetooth
Cons
- Heavier than comparable cranksets (680g vs ~540g for Shimano 105)
- Proprietary crank interface limits compatibility with other crank arms
- Some units report power accuracy issues (-2-3%) or calibration difficulties with certain devices
- Potential chainring compatibility issues requiring shims
Key Facts
- Spider-based power meter, 4-bolt 110BCD, 24mm spindle
- Weight: 668-680g with cranks
- Claimed accuracy: ±1.5%, some users report -2-3% vs trainer
Reviews & Ratings
The reviewer discusses the GEOID PM500 cycling power meter as an affordable entry-level option for cyclists who want consistent and reliable power data. They highlight its compatibility with Shimano 105 11-speed systems, lightweight design, long battery life, and accuracy of ±1.5%. The reviewer emphasizes that at $179, it provides meaningful data without the need for expensive alternatives.
AI Summary
Pros
- Affordable at $179
- Lightweight design at 680g
- Ultra long-life battery of 300 hours
- Accuracy of ±1.5% sufficient for training and testing
- Seamless sync with platforms like Zwift, TrainingPeaks, and Strava
- Pairs over ANT+ and Bluetooth to Garmin or Wahoo head units
- Includes tools, USB charger, and quick installation manual
- Compatible with Shimano 105 11-speed system via 110 BCD four-bolt design
Key Points
- Model: PM 500 spider power meter
- Crank: Senicx PR3 with 110 BCD four-bolt design
- Spindle: 24mm
- Weight: 680g
- Battery life: 300 hours
- Accuracy: ±1.5%
- Price: $179
- Compatibility: Shimano 105 11-speed
The reviewer tests the GEOID PM500 cycling power meter, which comes with cranks. They compare it to a cheaper spider-based power meter (Leico) and find the GEOID PM500 to be more accurate and reliable, especially after high-power sprints. The reviewer recommends the GEOID PM500 for its accuracy and value, noting it is a good option for those who need a power meter on a budget.
AI Summary
Pros
- Accurate power readings, with minimal deviation from reference pedals (Favera Assioma) in most tests.
- Comes with cranks and includes installation tools.
- Compatible with Shimano bottom brackets (24mm spindle).
- Has a calibration function via reverse pedaling.
- Good thermal compensation; maintains calibration during temperature changes.
- Reasonable price point for a complete crankset power meter.
Cons
- High weight: 770g for the complete set, heavier than Shimano 105 cranks (540g without chainrings).
- Low versatility: cranks are not sold separately, so changing crank length is not possible without buying a new set.
- May require a dedicated app for firmware updates (though not explicitly stated for GEOID, the reviewer notes the app is available).
Key Points
- The GEOID PM500 uses an accelerometer for cadence measurement, which improves accuracy over Hall-effect sensors.
- Claimed accuracy: ±1.5% for GEOID PM500.
- Comes with 24mm spindle, compatible with Shimano bottom brackets.
- Includes magnetic charging cable.
- The power meter is pre-calibrated and can be connected to a bike computer without additional software.
- The reviewer notes that the GEOID PM500 maintains calibration after high-power sprints, unlike the Leico power meter.
The reviewer purchased the GEOID PM500 power meter set from AliExpress for about £165. It is a crank set with a direct mount spider power meter, not including a chainring. The reviewer finds it affordable, easy to install, and aesthetically pleasing. They tested it and confirmed it pairs with devices and provides power readings.
AI Summary
Pros
- Very affordable at around £165
- Easy to install
- Looks good, 'meatier' aesthetic
- Uses same app as Machine power meter for setup and calibration
- Provides left and right power readings
- Accurate to 1.5%
- IP67 waterproof rated
- 300-hour battery life
- Pairs easily with devices like Garmin or Wahoo
- Comes with a charger and long cable
Cons
- Chainring not included
- Chainring bolts not included
- Heavier than Shimano GRX crank (about 100g more)
- Accuracy is 1.5% vs typical 1%
Key Points
- Spider-based power meter
- 110 BCD
- 24mm spindle
- Compatible with Shimano
- Uses lock ring and adapter for installation
- Torque spec: 34-40 Nm
- Charging port on spider
The GEOID PM500 cycling power meter is a budget-friendly option that appears to be a rebranded Magene P505 or P515 spider-based power meter. User tests show accuracy comparable to Garmin Rally pedals and direct drive trainers, but some concerns exist about potential offset shifts after high-power efforts, though not confirmed for this model. It is heavier than standard cranksets but offers good value for a second bike.
AI Summary
Pros
- Accuracy close to Garmin Rally pedals and direct drive trainers
- Significantly cheaper than Magene P515 (about 2/3 the price)
- Compatible with Shimano 4-bolt 110BCD cranksets
- Easy to install and use
Cons
- Heavier (680g) compared to standard 105 crank (545g)
- Potential offset shift after sprints (not confirmed for this model but seen in similar cheap meters)
- Limited long-term reliability data
Key Points
- Spider-based power meter, 4-bolt 110BCD, 24mm spindle
- Rebranded Magene P505 or P515
- Weight: 680g
- Compatible with Shimano cranks
- User tested against Tacx Neo 2T and Garmin Rally pedals
A Reddit user tested the Geoid PM500 power meter against a Tacx Neo 2T trainer and found it tracks well overall, with no offset issues after high-power efforts. It appears more responsive than the trainer but showed some cadence drops and a power drop without cadence change. Installation is straightforward, similar to Shimano cranks. However, a commenter noted the power scaling feature does not work, which is a drawback for users needing calibration.
AI Summary
Pros
- Tracks Tacx Neo 2T accurately overall
- No offset problems after 1000+ watt efforts
- More responsive to sudden power increases than the trainer
- Easy installation, similar to Shimano cranks
Cons
- Power scaling (slope adjustment) does not work, confirmed by support
- Some cadence drops observed (possibly glitches)
- One unexplained power drop without cadence change
Key Points
- Spider-based power meter, 4-bolt 110BCD, 24mm spindle
- Compatible with Shimano direct drive (MTB) interface
- Tested against Tacx Neo 2T with 2-second offset and 1-second smoothing
- No fumble after high-power efforts (common pitfall in other affordable meters)
The GEOID PM500 is a spider-based power meter with 4-bolt 110BCD 24mm interface, widely discussed as a rebranded or similar version of the Magene P505/P515. Users report it's typically priced between $170-$250, with weights around 668-680g including cranks. It uses a proprietary crank interface (paired with Senicx PR3 cranks) that is not compatible with other crank arms. The Senicx PR3 arms are more outward curved than Magene PES505, offering better front derailleur clearance, but the chainline is about 3mm shorter, which may cause chainstay clearance issues in some 2x setups. The power meter features ANT+/Bluetooth connectivity, claims ±1.5% accuracy, and works with Magene app and major cycling computers. User experiences on accuracy are mixed: some report good correlation after calibration, while others see -2-3% deviation vs smart trainers or encounter calibration difficulties with certain devices (Coros Dura, older Garmin). Some units have experienced a complete failure showing 0W while cadence still works; a possible fix is calibrating with a different head unit (e.g., iGPSport i830). No app activation is required, which is a plus over some Magene products. It is widely used in 1x setups. Overall, it is considered a budget-friendly alternative to Magene's offerings, often 2/3 the price in China, and a good value if performance is acceptable.
AI Summary
Pros
- Good value for money compared to similar power meters like Magene P515
- Compatible with major cycling apps and computers (Garmin, Wahoo, Magene, etc.) via ANT+/Bluetooth
- Uses improved 4-bolt clamping system compared to Magene's single-bolt design
- Works well with Shimano 105 chainrings and shifts perfectly; some users report accurate power after calibration
- Senicx PR3 crank arms provide more clearance for front derailleurs than Magene PES505 arms
- No app activation required, unlike some Magene products; simple install, pair, calibrate, ride
Cons
- Heavier than comparable models (approximately 680g vs 625g for Magene P515)
- Proprietary crank interface limits compatibility with other crank arms
- Potential chainring compatibility issues requiring shims
- Some users report power accuracy issues (e.g., -2-3% vs Kickr) and calibration difficulties with certain devices (Coros Dura, Garmin Edge 800)
- Chainline may be tighter than Magene PES505, potentially causing chainstay clearance issues with 2x setups
- Some units have failed completely, showing 0W while still transmitting cadence, and calibration fails; may require head-unit swap to recover
Key Points
- Price range: $170-$250 (often ~$171 on Amazon, ~1000 RMB in China)
- Weight: 668-680g with cranks
- Accuracy: ±1.5% claimed, some users report -2-3% vs trainer
- Crank interface: Proprietary (Senicx PR3, not compatible with Magene PES505 arms)
- Compatibility: ANT+/Bluetooth, works with Magene app, Garmin, Wahoo, etc.
- Cranks: Senicx PR3 with 4-bolt 110BCD, more outward curved than Magene PES505
- Chainline: ~3mm shorter than Magene PES505, may require spacer or spider swap for 2x clearance
- 1x setup: Supported, users report using 46T-50T chainrings
- No app activation required
- Some units have reported 0W failure; can sometimes be fixed by calibrating with a different head unit
Where to Buy
GEOID PM500 Cycling Bike Spider-Based Power Meter 4Bolt 110BCD 24mm Spindle Bicycle Crankarm for Shimano
Questions about GEOID PM500 Cycling Bike Spider-Based Power Meter 4Bolt 110BCD 24mm Spindle Bicycle Crankarm for Shimano
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