EGT Sensor Guide
AiM EGT (Exhaust Gas Temperature) Sensor Guide
This guide explains how the AiM EGT sensor works, what temperatures you should expect, and how to use EGT data for tuning with MyChron 5 and MyChron 6. This information is tailored for kart racers in New Zealand and Australia.
What the EGT sensor measures
The EGT sensor measures exhaust gas temperature inside the header pipe. It is one of the most important tuning tools for 2‑stroke engines.
Why EGT matters
- Shows whether the engine is running rich or lean
- Helps optimise jetting for performance and safety
- Indicates combustion efficiency
- Warns of overheating or detonation risk
- Tracks tuning changes across sessions
Ideal EGT temperature ranges
| Engine | Ideal EGT |
|---|---|
| Rotax | 550–650°C |
| Vortex | 600–680°C |
| IAME | 580–650°C |
| Yamaha KT100 | 500–600°C |
How to read EGT data
In AiM RaceStudio 3, EGT appears as a fast‑responding temperature curve. Look for:
- Rapid rise: engine under load
- Stable peak: correct jetting
- Sudden spikes: lean condition or detonation
- Low EGT: rich jetting or low load
Common EGT problems and symptoms
| Symptom | Likely Cause | Fix |
|---|---|---|
| EGT too high | Lean jetting, air leak, hot weather | Increase jet size, check seals |
| EGT too low | Rich jetting, cold weather | Reduce jet size |
| Erratic readings | Loose probe or wiring interference | Secure probe, reroute cable |
| Sudden drop | Probe failure or broken wire | Replace probe |
How to tune using EGT
EGT is one of the best tuning indicators for 2‑stroke engines:
- High EGT: engine running lean → increase jet size
- Low EGT: engine running rich → decrease jet size
For Rotax, Vortex, and IAME engines used in NZ & AU, EGT is extremely useful for fine‑tuning performance.
Maintenance tips
- Ensure probe is inserted to correct depth (usually 40–60mm)
- Check clamp tightness regularly
- Inspect wiring for heat damage
- Replace probe if readings become unstable