scooter / default rider 183 cm
Vespa ET4 150 vs Yamaha XMAX 400 ergonomics
Vespa ET4 150 and Yamaha XMAX 400 have modeled posture scores within three points for the 183 cm default rider. Treat this as a planning estimate; posture preference, data confidence, and a real test sit still matter.
Modeled fit comparison
Vespa ET4 150
All contacts reached
Yamaha XMAX 400
All contacts reached
The modeled scores are within three points, so the result does not distinguish a higher-scoring bike. Treat the result as a planning estimate and compare each bike's geometry confidence before a real test sit.
Rider fit: reaching the ground
The Vespa ET4 150 lists a 805 mm seat; the Yamaha XMAX 400 lists 800 mm — a 5 mm difference. Seat height is only a first-pass ground-reach input. It does not establish safety or actual foot contact. Seat width, suspension sag, boots, mobility, load, and individual proportions can materially change the result.
On seat height alone, the Yamaha XMAX 400 has the easier modeled ground reach. Load your measurements into the simulator to compare the model, then verify both motorcycles in person.
Geometry snapshot
| Spec | Vespa ET4 150 | Yamaha XMAX 400 |
|---|---|---|
| Seat height | 805 mm | 800 mm |
| Wheelbase | 1,280 mm | 1,567 mm |
| Wet weight | - | 210 kg |
| Displacement | 150 cc | 395 cc |
Posture metrics
Knee angle
- Vespa ET4 150
- Sport (57.7 deg)
- Yamaha XMAX 400
- Sport (58.3 deg)
Hip angle
- Vespa ET4 150
- Neutral (97.7 deg)
- Yamaha XMAX 400
- Neutral (91.5 deg)
Elbow angle
- Vespa ET4 150
- Relaxed (143.3 deg)
- Yamaha XMAX 400
- Relaxed (143.3 deg)
Torso lean
- Vespa ET4 150
- Neutral (9.5 deg)
- Yamaha XMAX 400
- Neutral (13.7 deg)