Cheat sheet
Gearing & shift drop
Road speed comes from RPM, tyre circumference and the gear × final-drive ratio. Shift landing is simpler: new RPM = shift RPM × next ratio ÷ current ratio. Keep the landing inside the useful power band, not merely below redline.
| Gear | Ratio | Speed | Speed | Next gear lands at |
|---|---|---|---|---|
| 1st | 3.50:1 | 61.3 km/h | 38.1 mph | 4,200 rpm |
| 2nd | 2.10:1 | 102.2 km/h | 63.5 mph | 4,850 rpm |
| 3rd | 1.45:1 | 148.0 km/h | 92.0 mph | 5,300 rpm |
| 4th | 1.10:1 | 195.1 km/h | 121.2 mph | 5,400 rpm |
| 5th | 0.85:1 | 252.5 km/h | 156.9 mph | 5,600 rpm |
| 6th | 0.68:1 | 315.6 km/h | 196.1 mph | — |
Speeds are generated by the live gear-ratio calculator. They are mathematical road speeds with no tyre growth or slip. The ratios are an example stack, not a recommendation for every engine.
| RPM drop | From 7,000 | From 8,000 | Next/current ratio |
|---|---|---|---|
| 10% | 6300 | 7200 | 0.90 |
| 15% | 5950 | 6800 | 0.85 |
| 20% | 5600 | 6400 | 0.80 |
| 25% | 5250 | 6000 | 0.75 |
| 30% | 4900 | 5600 | 0.70 |
| 35% | 4550 | 5200 | 0.65 |
| 40% | 4200 | 4800 | 0.60 |
A 25% drop means the next gear is 0.75 times the current ratio. Example: 1.10 to 0.83 lands close to this row. Compare the landing RPM with the dyno curve before changing ratios.