supermoto / default rider 183 cm
Aprilia SX 125 vs Yamaha XT 660 R Supermotard ergonomics
Aprilia SX 125 and Yamaha XT 660 R Supermotard 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
Aprilia SX 125
All contacts reached
Yamaha XT 660 R Supermotard
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 Aprilia SX 125 lists a 880 mm seat; the Yamaha XT 660 R Supermotard lists 875 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 XT 660 R Supermotard 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 | Aprilia SX 125 | Yamaha XT 660 R Supermotard |
|---|---|---|
| Seat height | 880 mm | 875 mm |
| Wheelbase | 1,425 mm | 1,490 mm |
| Wet weight | 136 kg | - |
| Displacement | 124 cc | 660 cc |
Posture metrics
Knee angle
- Aprilia SX 125
- Sport (58.0 deg)
- Yamaha XT 660 R Supermotard
- Sport (58.1 deg)
Hip angle
- Aprilia SX 125
- Neutral (94.6 deg)
- Yamaha XT 660 R Supermotard
- Neutral (93.2 deg)
Elbow angle
- Aprilia SX 125
- Relaxed (143.3 deg)
- Yamaha XT 660 R Supermotard
- Relaxed (143.3 deg)
Torso lean
- Aprilia SX 125
- Neutral (11.7 deg)
- Yamaha XT 660 R Supermotard
- Neutral (12.6 deg)