Ridley Probe RS geometryMTB · 2024 · 4 sizes, from S to XL
The Ridley Probe RS is a mtb bike available in 4 sizes, from S to XL. Stack ranges from 606 to 634 mm and reach from 405 to 480 mm. Its position sits between racing and endurance. All sizes share 430 mm chainstays. Data from 2024; geometry from 2023 is also available.
What size Probe RS 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 Ridley. The ones that matter most for choosing a size are in bold.
| Size | S | M | L | XL |
|---|---|---|---|---|
| Stack | 606 | 606 | 620 | 634 |
| Reach | 405 | 430 | 455 | 480 |
| Effective top tube | 578 | 604 | 633 | 662 |
| Head tube length | 100 | 100 | 115 | 130 |
| Head angle | 68.5° | 68.5° | 68.5° | 68.5° |
| Chainstay length | 430 | 430 | 430 | 430 |
| Wheelbase | 1,089 | 1,141 | 1,145 | 1,176 |
| BB drop | 63 | 63 | 63 | 63 |
| Seat tube (method not stated) | 400 | 430 | 470 | 520 |
| Seat angle (method not stated) | 74.0° | 75.0° | 76.0° | 77.0° |
Source: Ridley 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 Probe RS 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 606/405 mm in size S to 634/480 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 Probe RS in size M?
Stack of 606 mm and reach of 430 mm, with an effective top tube of 604 mm and a head angle of 68.5°.
Is the Probe RS a racing or an endurance bike?
In between. In size M its stack-to-reach ratio is at percentile 60 of mtb bikes: neither very low nor very tall.