Cube Reaction C:68X SLX geometryMTB · 2026 · 4 sizes, from S to XL
The Cube Reaction C:68X SLX is a mtb bike available in 4 sizes, from S to XL. Stack ranges from 609 to 639 mm and reach from 410 to 482 mm. Its position sits between racing and endurance. All sizes share 425 mm chainstays.
What size Reaction C:68X SLX 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 Cube. The ones that matter most for choosing a size are in bold.
| Size | S | M | L | XL |
|---|---|---|---|---|
| Stack | 609 | 612 | 624 | 639 |
| Reach | 410 | 435 | 456 | 482 |
| Effective top tube | 575 | 605 | 630 | 660 |
| Head tube length | 94 | 97 | 110 | 126 |
| Head angle | 69.0° | 69.0° | 69.0° | 69.0° |
| Chainstay length | 425 | 425 | 425 | 425 |
| Wheelbase | 1,091 | 1,117 | 1,143 | 1,174 |
| Seat tube (method not stated) | 370 | 420 | 450 | 510 |
| Seat angle (method not stated) | 74.7° | 74.3° | 74.3° | 74.3° |
Source: Cube 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 Reaction C:68X SLX 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 609/410 mm in size S to 639/482 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 Reaction C:68X SLX in size M?
Stack of 612 mm and reach of 435 mm, with an effective top tube of 605 mm and a head angle of 69.0°.
Is the Reaction C:68X SLX 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.