RPM Graph Analysis
RPM Graph Analysis Guide
This guide explains how to analyse RPM data from AiM MyChron 5 and MyChron 6 using RaceStudio 3. Understanding RPM behaviour is essential for gearing, tuning, and improving driving performance for kart racers in New Zealand and Australia.
Why RPM analysis matters
RPM data reveals how efficiently your engine and drivetrain are performing. It helps you:
- Choose the correct gear ratio
- Identify over‑revving or bogging
- Understand braking and corner entry behaviour
- Improve throttle application and exit speed
- Compare performance between sessions or drivers
1. Understanding the RPM trace
The RPM trace is a line graph showing engine speed over time. Key features include:
- Peaks — maximum RPM on straights
- Drops — braking and corner entry
- Rises — acceleration out of corners
- Flat sections — rev limiter or gearing limit
2. Identifying correct gearing
Gearing is correct when:
- You reach peak RPM near the end of the longest straight
- You do not hit the rev limiter too early
- The engine does not bog exiting slow corners
Signs of incorrect gearing
- Over‑revving: RPM hits limiter early → gear up (bigger rear sprocket)
- Bogging: RPM drops too low on exit → gear down (smaller rear sprocket)
3. Analysing corner entry
The RPM trace shows how effectively you brake and rotate the kart:
- Sharp RPM drop: heavy braking
- Smooth drop: controlled braking
- Sudden dip: over‑braking or locking the rear
4. Analysing corner exit
The rate of RPM rise shows how well you accelerate:
- Fast rise: strong exit speed
- Slow rise: poor line or too much steering input
- Flat spot: wheelspin or bogging
5. Comparing two laps or drivers
Overlaying two RPM traces reveals:
- Who brakes later
- Who carries more corner speed
- Who accelerates earlier
- Who gears correctly for the track
6. Common RPM patterns and what they mean
| RPM Pattern | Meaning | Fix |
|---|---|---|
| Hitting limiter early | Over‑revving | Gear up |
| Slow RPM rise | Poor exit speed | Improve line or reduce steering input |
| Sudden RPM dip | Rear wheel lock or over‑braking | Brake smoother |
| Low peak RPM | Gearing too tall | Gear down |
7. What RPM should your engine reach?
Typical safe RPM ranges:
- Rotax: 14,000–14,800 rpm
- Vortex: 15,000–15,500 rpm
- IAME: 15,000–16,000 rpm
- Briggs: 6,000–6,500 rpm