scooter / default rider 183 cm
BMW C 650 GT vs Vespa ET4 150 ergonomics
BMW C 650 GT and Vespa ET4 150 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
BMW C 650 GT
All contacts reached
Vespa ET4 150
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 BMW C 650 GT lists a 805 mm seat; the Vespa ET4 150 lists 805 mm, within a few millimetres of each other. 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.
Geometry snapshot
| Spec | BMW C 650 GT | Vespa ET4 150 |
|---|---|---|
| Seat height | 805 mm | 805 mm |
| Wheelbase | 1,591 mm | 1,280 mm |
| Wet weight | 261 kg | - |
| Displacement | 647 cc | 150 cc |
Posture metrics
Knee angle
- BMW C 650 GT
- Sport (58.4 deg)
- Vespa ET4 150
- Sport (57.7 deg)
Hip angle
- BMW C 650 GT
- Neutral (91.0 deg)
- Vespa ET4 150
- Neutral (97.7 deg)
Elbow angle
- BMW C 650 GT
- Relaxed (143.3 deg)
- Vespa ET4 150
- Relaxed (143.3 deg)
Torso lean
- BMW C 650 GT
- Neutral (14.0 deg)
- Vespa ET4 150
- Neutral (9.5 deg)