R.EX 900 2025
How current the bike is — newer chassis, motor and battery score higher. 10 = brand-new, 0 = legacy.
The R.EX 900 is Rotwild's all-mountain take on its R.EXC enduro race platform, built around a full Polydynamic Carbon frame and the Mid-High Pivot suspension that pairs 150 mm of rear travel with a 160 mm fork. It runs an MX wheel setup and a roomy 864 Wh in-house IPU900 carbon battery feeding the DJI Avinox M1 motor, claimed at 105 Nm and up to 1000 W.
Geometry is consistent and modern across M, L and XL: a 64 degree head angle, 78 degree effective seat angle and short 439 mm chainstays on every size, with reach growing 462 to 487 to 512 mm. The ACROS MOD headset allows angle and reach tweaks, so the figures above are the standard configuration rather than a fixed limit.
The three builds share frame, motor, battery and geometry, so the choice is about parts and budget. Core (8990 EUR) is the value pick with a Fox 36 Performance fork, Magura MT5 brakes and a Shimano XT mechanical drivetrain. Pro (9990 EUR) swaps to a RockShox Lyrik Select+, SRAM Maven Bronze stoppers and wireless GX Transmission AXS for a modest step up. Ultra (12490 EUR) is the flagship with Fox Factory Kashima suspension, X0 Transmission, carbon Crankbrothers wheels and the lightest claimed weight at 22.0 kg.
Geometry · hover a row to highlight the measurement on the bike
| M | L | XL | |
|---|---|---|---|
| Reach | 462 mm | 487 mm | 512 mm |
| Stack | 638 mm | 642 mm | 651 mm |
| Seattube | 445 mm | 475 mm | 511 mm |
| Chainstay | 439 mm | 439 mm | 439 mm |
| Headtube Angle | 64° | 64° | 64° |
| Seattube Angle (eff) | 78° | 78° | 78° |
| Wheelbase | 1246 mm | 1273 mm | 1303 mm |
| Headtube | 110 mm | 115 mm | 125 mm |
| BB Height | 337 mm | 337 mm | 337 mm |
| Standover | 735 mm | 733 mm | 732 mm |
| Front Centre | 807 mm* | 834 mm* | 864 mm* |
Trims · 3
Core | Pro | Ultra | |
|---|---|---|---|
| Motor | Avinox M1 · 105 Nm · all trims | ||
| Battery | Rotwild IPU900 · 864 Wh · all trims | ||
| Travel F/R | 160/150 mm · all trims | ||
| Frame | Carbon · all trims | ||
| Fork | FOX 36 Float Performance, 160 mm / Grip / 2-Pos | ROCK SHOX Lyrik Select+, 160 mm / CHARGER 3.1 / RC2 | FOX 36 Float Factory Kashima, 160 mm / Grip X / HSC/LSC / LSR |
| Shock | FOX Float X Performance, 185 x 55 mm / 2-Pos | ROCK SHOX Super Deluxe Select+, 185 x 55 mm / 3P | FOX Float X Factory Kashima, 185 x 55 mm / 2-Pos Adjust |
| Headset | ACROS RW EXC 1.5 - MOD, 0° / mod56/56 · all trims | ||
| Stem | e*thirteen Plus 35, 50 mm Length | ROTWILD S120, 35 mm Length | ROTWILD S120, 35 mm Length |
| Handlebar | e*thirteen Plus, 20 mm Rise / 780 mm Width | ROTWILD B280, 15 mm Rise / 780 mm Width | ROTWILD B220 Carbon, 15 mm Rise / 780 mm Width |
| Grips | ERGON GD10 Slim Factory Frozen · all trims | ||
| Saddle | ERGON SM Sport | ERGON SM Sport | ERGON SM Pro |
| Seatpost | 8PINS NGS2.0, fully integrated, 192 mm (M) / 210 mm (L) / 228 mm (XL) · all trims | ||
| Brakes | Front: MAGURA MT5 HC-W; Rear: MAGURA MT5 Shiftmix | SRAM Maven Bronze (front and rear) | SRAM Maven Silver (front and rear) |
| Rear derailleur | SHIMANO XT 8100 SGS Hyperglide+ | SRAM GX Eagle Transmission AXS | SRAM X0 Eagle Transmission AXS |
| Crank | e*thirteen Plus, 165 mm (M/L) / 170 mm (XL), 34T direct mount chainring | e*thirteen Plus, 165 mm (M/L) / 170 mm (XL), e*thirteen Spider / SRAM 34T chainring | e*thirteen Race Carbon, 165 mm (M/L) / 170 mm (XL), e*thirteen Spider / SRAM 34T chainring |
| Shifters | SHIMANO XT 8100 I-Spec EV | SRAM AXS Pod | SRAM AXS Pod |
| Cassette | SHIMANO CS 6100, 10-51T / 12-Speed | SRAM GX Eagle XS 1270, 10-52T / 12-Speed | SRAM GX Eagle XS 1275, 10-52T / 12-Speed |
| Chain | SHIMANO HG 7100, 12-Speed | SRAM GX Eagle Transmission, 12-Speed | SRAM X0 Eagle Transmission, 12-Speed |
| Drivetrain | SHIMANO XT 8100 SGS Hyperglide+; e*thirteen Plus, 165 mm (M/L) / 170 mm (XL), 34T direct mount chainring; SHIMANO XT 8100 I-Spec EV; SHIMANO CS 6100, 10-51T / 12-Speed; SHIMANO HG 7100, 12-Speed | SRAM GX Eagle Transmission AXS; e*thirteen Plus, 165 mm (M/L) / 170 mm (XL), e*thirteen Spider / SRAM 34T chainring; SRAM AXS Pod; SRAM GX Eagle XS 1270, 10-52T / 12-Speed; SRAM GX Eagle Transmission, 12-Speed | SRAM X0 Eagle Transmission AXS; e*thirteen Race Carbon, 165 mm (M/L) / 170 mm (XL), e*thirteen Spider / SRAM 34T chainring; SRAM AXS Pod; SRAM GX Eagle XS 1275, 10-52T / 12-Speed; SRAM X0 Eagle Transmission, 12-Speed |
| Wheels | CRANKBROTHERS Synthesis Enduro (front 31.5 mm / rear 29.5 mm) | CRANKBROTHERS Synthesis Enduro (front 31.5 mm / rear 29.5 mm) | CRANKBROTHERS Synthesis Enduro Carbon (front 31.5 mm / rear 29.5 mm) |
| Tyres | SCHWALBE Albert Evo, Trail / Soft / TLE, 29x2.5 front / 27.5x2.5 rear · all trims | ||
| Weight | 22.8 kg | 22.6 kg | 22 kg |
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