Cube mountain bike sizing: Stereo, Reaction, AMS and Stereo Hybrid
Cube covers the mountain from four angles. The Stereo is the all round trail full suspension bike, the Reaction is the cross country hardtail, the AMS is the light, lively down country full suspension bike, and the Stereo Hybrid is the trail e MTB. One thing worth knowing before anything else: Cube tends to run large for its size labels, so many riders end up one size smaller than they expect. Choose by reach and height, remembering that sizing down feels more playful and sizing up feels more stable. See what is in stock on our Cube collection.
Please note. These recommendations are indicative and a starting point, not a guarantee of fit. Proportions, flexibility and terrain change the answer, so read the reach and stack numbers with the height bands and confirm against the exact bike before you buy.
Quick size finder
| Rider height | Leg length (inseam) | Stereo (trail) | Reaction (hardtail) | AMS (down country) | Stereo Hybrid (e-MTB) |
|---|---|---|---|---|---|
| 155 to 165 cm | 68 to 73 cm | – | XS | SM | – |
| 165 to 173 cm | 73 to 78 cm | S | S | SM | S |
| 173 to 180 cm | 78 to 82 cm | M | M | MD | M |
| 180 to 188 cm | 82 to 87 cm | L | L | LG | L |
| 188 to 200 cm | 87 to 93 cm | XL | XL | XL | XL |
How to measure yourself
Height. Stand barefoot against a wall, heels together and back straight. Mark the top of your head and measure straight down to the floor.
Leg length (inseam). Barefoot, feet about 15 cm apart, press a hardback book spine up into your crotch as a saddle would sit. Measure from the top of the book to the floor. On a mountain bike your inseam helps judge standover clearance and footing at a stop.
Cube Stereo
The Stereo is an efficient, neutral trail bike that climbs superbly and stays composed on descents rather than feeling hyper playful.
| Size | Reach (mm) | Stack (mm) | Rider height |
|---|---|---|---|
| S | 430 | 615 | 163 to 172 cm |
| M | 450 | 624 | 170 to 180 cm |
| L | 475 | 633 | 178 to 188 cm |
| XL | 502 | 651 | 186 to 198 cm |
Fit character: neutral and efficient, a composed all round trail bike.
Cube Reaction
The Reaction is a comfort leaning cross country and marathon hardtail with a fairly upright position. The smallest size rolls on 27.5 inch wheels.
| Size | Reach (mm) | Stack (mm) | Rider height |
|---|---|---|---|
| XS | 385 | 600 | 155 to 165 cm |
| S | 405 | 612 | 165 to 173 cm |
| M | 422 | 621 | 172 to 180 cm |
| L | 439 | 630 | 178 to 186 cm |
| XL | 456 | 639 | 184 to 192 cm |
Fit character: upright and tour friendly, a comfort biased XC hardtail.
Cube AMS
The AMS is a light, lively down country bike that mixes a sporty position with stability at speed. It uses Cube's SM to XL size labels.
| Size | Reach (mm) | Stack (mm) | Rider height |
|---|---|---|---|
| SM | 401 | 592 | 157 to 173 cm |
| MD | 423 | 601 | 168 to 180 cm |
| LG | 445 | 611 | 178 to 190 cm |
| XL | 466 | 625 | 185 to 201 cm |
Fit character: light and lively, sporty yet stable down country.
Cube Stereo Hybrid
The Stereo Hybrid is the trail e MTB, roomy and planted on descents with an upright pedalling position. Its reach mirrors the regular Stereo.
| Size | Reach (mm) | Stack (mm) | Rider height |
|---|---|---|---|
| S | 425 | 606 | 163 to 173 cm |
| M | 452 | 620 | 170 to 180 cm |
| L | 477 | 632 | 178 to 188 cm |
| XL | 512 | 658 | 186 to 200 cm |
Fit character: roomy and planted, a stable trail e MTB.
What Cube riders find
The theme owners return to most is that Cube runs large, so a rider around 178 cm often lands on a medium rather than a large, especially on the Stereo and Stereo Hybrid. Reviewers praise the Stereo as a superb climber and composed descender, the Reaction as a comfortable tour and marathon hardtail, and the AMS as a balanced, lively down country bike that is stable at speed yet playful. Its shortish reach numbers mean the AMS fits fairly compact for its labels.
Between two sizes?
Given that Cube runs large, riders on a boundary often do best sizing down, which also gives a more playful, flickable feel on tight trails. Size up only if you want a longer, more stable cockpit for speed and steep descents, then fine tune with stem and bar choice. Comparing reach and stack with a bike you already ride and know fits is the most reliable check.
Shop Cube mountain bikes
Check current models, builds and availability on our Cube collection.
Not sure which Cube suits your trails, or whether to size down? We are happy to help. Talk to our concierge.
Stack and reach figures are drawn from official Cube data where possible. Rider height bands are indicative estimates rather than official Cube numbers, since Cube publishes per size heights through an interactive tool. The Reaction is offered in an XXL on some builds that is not shown here; confirm availability. Always confirm geometry against the exact bike and model year before buying.
