sport-touring / default rider 183 cm
BMW R100RS vs Ducati ST4 ergonomics
BMW R100RS and Ducati ST4 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 R100RS
All contacts reached
Ducati ST4
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 R100RS lists a 820 mm seat; the Ducati ST4 lists 820 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 R100RS | Ducati ST4 |
|---|---|---|
| Seat height | 820 mm | 820 mm |
| Wheelbase | 1,466 mm | 1,430 mm |
| Wet weight | 230 kg | - |
| Displacement | 980 cc | 916 cc |
Posture metrics
Knee angle
- BMW R100RS
- Sport (57.9 deg)
- Ducati ST4
- Sport (57.8 deg)
Hip angle
- BMW R100RS
- Neutral (90.1 deg)
- Ducati ST4
- Neutral (90.9 deg)
Elbow angle
- BMW R100RS
- Relaxed (143.3 deg)
- Ducati ST4
- Relaxed (143.3 deg)
Torso lean
- BMW R100RS
- Neutral (13.3 deg)
- Ducati ST4
- Neutral (12.9 deg)