naked / default rider 183 cm
Triumph Speed Four vs Yamaha MT-15 ergonomics
Triumph Speed Four and Yamaha MT-15 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
Triumph Speed Four
All contacts reached
Yamaha MT-15
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 Triumph Speed Four lists a 810 mm seat; the Yamaha MT-15 lists 810 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 | Triumph Speed Four | Yamaha MT-15 |
|---|---|---|
| Seat height | 810 mm | 810 mm |
| Wheelbase | 1,394 mm | 1,335 mm |
| Wet weight | - | 138 kg |
| Displacement | 599 cc | 155 cc |
Posture metrics
Knee angle
- Triumph Speed Four
- Sport (61.5 deg)
- Yamaha MT-15
- Sport (61.3 deg)
Hip angle
- Triumph Speed Four
- Neutral (92.8 deg)
- Yamaha MT-15
- Neutral (94.5 deg)
Elbow angle
- Triumph Speed Four
- Relaxed (143.3 deg)
- Yamaha MT-15
- Relaxed (143.3 deg)
Torso lean
- Triumph Speed Four
- Neutral (12.0 deg)
- Yamaha MT-15
- Neutral (11.0 deg)