Frame Information
The Curtis XR is an absolute enduro, trail, and all-mountain weapon.
Designed as a 150mm travel single-pivot dirt bike, its 64-degree head tube and 77-degree seat tube angles provide a geometry that allows you to climb with ease, rail corners, and go downhill incredibly fast.
The material we chose for the frame is Reynolds 853, and the swingarm is T45 Aerospace grade steel, a tube set we know, love and trust from decades of national title-winning bikes.
The reasons a Curtis feels different.
Since 1972, we've built steel frames recognised among the finest in England.
Fillet Brazing
Brian Curtis' signature brazing technique creates beautiful rippled joints and airtight tubes, protecting Curtis frames from internal rust.
Discover fillet brazing
Made To Order
Every frame is made to order in Somerset, this is what makes a Curtis special. In the configurator, change every part of your new frame.
See how we build each frame
Premium Steel
Reynolds, Columbus, Dedacciai, and T45 are cherry picked frame by frame for an unmatched strength-to-weight ratio, and ride feel.
Explore our premium steelFactory Pilots Riding The XR
Chris Whitehurst
Chris adventure man Whitehurst Enduro racer has competed in many enduro races throughout Europe including 4 Trans province, 3 Stoneking rallies and 2 trans Savoie all are 6 day events plus many UK enduro racers like...
Jim Davage
Jim Davage, Downhill racer, dirt jumper and chief test pilot for prototypes Jim has been in the family for ever and has taken his Thumpercross DH bike to many a podium spot and rides his signature...
Model Differences
Latest Review
Brian Curtis has been making frames for nearly 50 years and, together with Gary Woodhouse, he’s built a reputation for beautiful yet robust brazed steel bikes. The XR650’s outwardly simple yet sorted single-pivot frame combines a tautly-sprung ride feel with stunning looks.
Technical Specifications
| Specification | Detail |
|---|---|
| Shock Length | 230 x 60mm (150/155mm travel) |
| Seat tube | 31.6mm |
| Head tube | Tapered compatibility (Top: ZS44/28.6 | Bottom: EC44/40) |
| Bottom bracket | 73mm BSA threaded |
| Frame Weight | 7.23 lbs / 3.86kg (18" frame without shock) |
| Complete Bike Weight | 32.04 lbs / 14.53kg |
| Chain Guide | Includes ISCG mounts as standard |
Tubing Used
| Tubing | Material |
|---|---|
| Swingarm (seatstays, chainstays) | T45, 3 different weight options depending on riding intensity |
| Downtube | T45 |
| Top tube | Reynolds 853 |
| Seat tube | Reynolds 631 |
Geometry Chart
| XR650 | XS | S | M | L | XL | XXL |
|---|---|---|---|---|---|---|
| S/T | 15 | 16 | 17 | 18 | 19 | 20 |
| FORK | 170 | 170 | 170 | 170 | 170 | 170 |
| H/T | 100 | 100 | 110 | 110 | 120 | 130 |
| H/T ANGLE | 64 | 64 | 64 | 64 | 64 | 64 |
| S/T ANGLE | 76 | 76 | 76 | 76 | 76 | 76 |
| REACH | 440 | 450 | 465 | 480 | 495 | 515 |
| STACK | 579 | 579 | 588 | 588 | 597 | 606 |
| B/B DROP | -14 | -14 | -14 | -14 | -14 | -14 |
| B/B HEIGHT | 340 | 340 | 340 | 340 | 340 | 340 |
| C/S | 435 | 435 | 435 | 435 | 435 | 435 |
| XR29 | XS | S | M | L | XL | XXL |
|---|---|---|---|---|---|---|
| S/T | 15 | 16 | 17 | 18 | 19 | 20 |
| Fork | 160 | 160 | 160 | 160 | 160 | 160 |
| H/T | 100 | 100 | 110 | 110 | 120 | 130 |
| H/T Angle | 64 | 64 | 64 | 64 | 64 | 64 |
| S/T Angle | 77 | 77 | 77 | 77 | 77 | 77 |
| Reach | 440 | 450 | 465 | 480 | 495 | 515 |
| Stack | 604 | 604 | 613 | 613 | 622 | 631 |
| B/B Drop | -28 | -28 | -28 | -28 | -28 | -28 |
| B/B Height | 340 | 340 | 340 | 340 | 340 | 340 |
| C/S | 449 | 449 | 449 | 449 | 449 | 449 |










