supermoto / default rider 183 cm
Aprilia SX 125 vs Yamaha XT 660 R Supermotard ergonomics
Aprilia SX 125 and Yamaha XT 660 R Supermotard land within a few ergonomic points for the default rider, so the better choice comes down to posture preference and bike category.
Fit verdict
Aprilia SX 125
All contacts reached
Yamaha XT 660 R Supermotard
All contacts reached
The two bikes are close enough that posture preference matters more than the overall score.
Rider fit: reaching the ground
The Aprilia SX 125 has a 880 mm seat; the Yamaha XT 660 R Supermotard sits at 875 mm — a 5 mm difference. As a rule of thumb you flat-foot a bike when your inseam roughly matches its seat height: about 88 cm for the Aprilia SX 125 and 88 cm for the Yamaha XT 660 R Supermotard.
That makes the Yamaha XT 660 R Supermotard the easier reach to the ground — the safer pick for shorter riders or anyone who wants both feet planted at a stop — while the Aprilia SX 125 gives taller riders more legroom and a more open knee bend. Load your own height and inseam into the simulator to see exactly how each one fits you.
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)