Wilier Triestina 503X Race geometryMTB · 2024 · 4 sizes, from S to XL
The Wilier Triestina 503X Race is a mtb bike available in 4 sizes, from S to XL. Stack ranges from 617 to 650 mm and reach from 395 to 444 mm. Its geometry is tall and short, built for comfort. All sizes share 440 mm chainstays.
What size 503X Race do I need?
Enter the stack and reach of a bike that fits you well and we will tell you which size is closest and how to set it up.
Enter your stack and reach to see which size fits you best.
Geometry chart by size
Measurements in mm and degrees, as published by Wilier Triestina. The ones that matter most for choosing a size are in bold.
| Size | S | M | L | XL |
|---|---|---|---|---|
| Stack | 617 | 628 | 639 | 650 |
| Reach | 395 | 412 | 428 | 444 |
| Effective top tube | 580 | 600 | 625 | 650 |
| Seat tube (centre-to-top) | 420 | 450 | 490 | 530 |
| Seat tube (centre-to-centre) | 360 | 390 | 430 | 470 |
| Head tube length | 100 | 112 | 124 | 135 |
| Head angle | 70.5° | 70.5° | 70.5° | 70.5° |
| Chainstay length | 440 | 440 | 440 | 440 |
| Seat angle (method not stated) | 73.5° | 73.5° | 73.0° | 72.5° |
Source: Wilier Triestina official website · data from 11 Nov 2026. Spot a mistake?
Stack and reach of every size
Higher means a taller front end; further right means a longer reach. The blue dot is your search.
Character of each size
Compared with other mtb bikes. Further right means more of that quality.
Bikes with similar geometry (size M)
The closest size of other mtb models, by stack and reach.
Frequently asked questions
What size 503X Race do I need?
It depends on your position, not just your height. The most reliable way is to compare the stack and reach of a bike that fits you with those of each size (from 617/395 mm in size S to 650/444 mm in size XL). The size finder on this page shows the closest size and the stem and spacers you would need.
What are the stack and reach of the 503X Race in size M?
Stack of 628 mm and reach of 412 mm, with an effective top tube of 600 mm and a head angle of 70.5°.
Is the 503X Race a racing or an endurance bike?
Endurance. In size M its stack-to-reach ratio is at percentile 95 of mtb bikes: a tall, short position.