2020 Specialized Fuse M4 vs 2020 Specialized Stumpjumper ST Alloy 29
The S is the Specialized Stumpjumper ST Alloy 29 size closest to your XS Specialized Fuse M4. We match frame stack and reach. This is a geometry comparison, not a fit recommendation; stem, spacers, handlebars and saddle setup also affect your riding position.
What changes on the Specialized Stumpjumper ST Alloy 29
Compared with the Specialized Fuse M4 in XS, the Specialized Stumpjumper ST Alloy 29 in S places the top of the head tube 6 mm lower and 5 mm further forward, relative to the bottom bracket. Its wheelbase is 29 mm longer, which can contribute to stability at speed.
- Frame stack
- −6 mm
- Lower front end
- Frame reach
- +5 mm
- Longer frame reach
- Wheelbase
- +29 mm
- Longer: steadier at speed
- Head angle
- ±0.0°
- About the same head angle
- Chainstays
- n/a
- One of the bikes has no number for this
The two frames
We can't draw these frames yet. The Specialized Fuse M4 numbers we have for size XS are missing the chainstay length. The numbers below still compare.
Geometry side by side
| Measurement | Specialized Fuse M4 XS | Specialized Stumpjumper ST Alloy 29 S | Difference |
|---|---|---|---|
| Reach | 400mm | 405mm | +5 mm |
| Stack | 625mm | 619mm | −6 mm |
| Head tube angle | 66.5° | 66.5° | ±0.0° |
| Seat tube angle | 74° | 74.8° | +0.8° |
| Wheelbase | 1122mm | 1151mm | +29 mm |
| Standover | 727mm | 756mm | +29 mm |
| Seat tube length | 340mm | 380mm | +40 mm |
| Fork length | 540mm | 560mm | +20 mm |
| Head tube length | 95mm | 100mm | +5 mm |
| Chainstay length | not listed | 437mm | |
| BB drop | not listed | 33mm | |
| BB height | not listed | 341mm |
Differences are the Specialized Stumpjumper ST Alloy 29 minus the Specialized Fuse M4. Full charts: 2020 Specialized Fuse M4, 2020 Specialized Stumpjumper ST Alloy 29.
Where each sits in its class
Specialized Fuse M4Specialized Stumpjumper ST Alloy 29
Each bike is ranked against the other trail bikes on Quiver, on frame geometry alone. Not your hand position or ride feel.
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