| MODEL | BETA RR 400 ENDURO 2005 - 2006 |
| Year | 2005 - 2006 |
| Engine Type | Four stroke, single cylinder, DOHC, 4 valves |
| Displacement / Capacity | 398 cc / 24.3 cu in |
| Bore X Stroke | 95 x 56.2 mm |
| Compression Ratio | 11.0:1 |
| Cooling System | Air cooled |
| Max Power | — |
| Max Torque | — |
| Ignition | DC-CDI without trembler with variable ignition timing, Kokusan type |
| Induction | Keihin FCR-MX 39 |
| Start System | Electric and kick |
| TRANSMISSION SPECS | |
| Lubrication | Forced, 2 oil pumps |
| Gear Box | 6 Speed |
| Clutch | — |
| Final Drive | Chain |
| CHASSIS SPECS | |
| Frame | Molybdenum steel with double cradle split above the exhaust port |
| Front Suspension | Hydraulic USD fork, 45 mm |
| Rear Suspension | Monoshock with progressive compound lever |
| Front Brakes | Single 255 mm disc, 2 piston caliper |
| Rear Brakes | Single 240 mm disc, 1 piston caliper |
| DIMENSION SPECS | |
| Overall Length | — |
| Overall Width | — |
| Overall Height | — |
| Seat Height | 940 mm / 37 in |
| Wheelbase | — |
| Ground Clearance | 320 mm / 12.6 in |
| Dry Weight | 117.5 kg / 258 lbs |
| Wet Weight | — |
| WHEEL SPECS | |
| Front Tyre | 90/90 -21 |
| Rear Tyre | 140/80 -18 |
| FUEL SYSTEM | |
| Fuel Capacity | 8.5 Litres / 2.2 US gal |
| Fuel Consumption | — |
| Top Speed | — |
The 400 slotted between the 250 and 450 in Beta's first KTM-based four-stroke enduro range. A magazine test described it as easy to ride, with smooth linear power and strong low-rev torque, and stable on fast rough ground though the front end could push in tight corners.
