Moving up from that $27 dual channel thermometer gives increasing functionality:
- Dual Display show both readings
- Min/Max and internal clock capture the value, and what time it was recorded
- Can work with multiple types of thermocouple wires J, K,T, E, N, R, S.
That's handy if your bike is already wired for a CHT, but uses something different than a 'K type' thermocouple - Logging function. Manually trigger storage, or set up a periodic timer to capture samples
- PC interface - download logged data for review, processing and display
Fluke 54-II
$369
Temperature accuracy
Above -100 ┬░C: J, K, T, E, and N-type: ┬▒[0.05% + 0.3┬░C]*
R and S-type: ┬▒[0.05% + 0.4┬░C]*
Advantages: Fluke quality, accurate, easy to use, settings are persistent. 1000hr battery life. PC software is not required to review logged data, but convenient.
Disadvantages: Fluke does not include the PC software and IR adapter in the price. That accessory is around $180. Second meter itself is expensive. There are competitors which make logging thermometers, include the PC software, and sell for less. Will post links later. The pictured meter was lightly used, and discounted.
--- Logging example - CHT sensor location ---
Plug sensors are commonly used as well as other mounts around the cyl head. One convenient location is a head bolt. How do the two readings compare? Perfect test for a dual channel logging meter, capturing data on exactly the same run.
Probe installation - Stock 1999 Elite SA50. Rear headbolt, closest to cooling fan. 2nd probe on plug.
Test run - approx 3 miles, temperature readings are logged every 10 sec
Results: Temperature differences between sensor placements are large. Plug sensor recorded temp peaks on hills that the head bolt location did not register.
Second test - different scooter Yamaha QT50
More testing of CHT probe placement. Different scooter, no forced air cooling. Exact same test route.
Probe installation:
Results: Temperature differences between sensor placements remains large. QT50 is running hot, better go find that larger jet in the garage...