Beta RR 4T 350 Enduro




Make Model

Beta RR 4T 350 Enduro




Four stroke, single cylinder with countershaft, DOHC


349 cc / 21.3 cu in

Bore x Stroke

88 x 57.4 mm

Compression Ratio



Forced, 2 oil pumps

Cooling System

Liquid cooled, forced by pump


Fuel injection


DC-CDI with variable ignition timing, Kokusan

Spark Plug



Electric and kick


Wet multi-disc


6 Speed

Final Drive


Gear Ratios

1st 12:31 / 2nd 15:28 / 3rd 19:28 / 4th 20:24 / 5th 27:27 / 6th 28:24

Primary Drive



Molybdenum steel with double cradle split above exhaust port. Air filter access from the side

Front Suspension

48 mm Ø Sachs USD fork, adjustable compression and rebound, TFX technology, 11.4 in wheel travel.

Front Wheel Travel

290 mm / 11.4 in

Rear Suspension

Sachs shock w/adjustable rebound and hi/low speed compression

Rear Wheel Travel

290 mm / 11.4 in

Front Brakes

Single wave Ø 260 mm floating disc, 2 piston floating caliper

Rear Brakes

Single Ø 240 mm disc,  1 piston floating caliper

Front Wheel

1.60 x 21

Rear Wheel

2.15 x 18

Front Tyre

90/90 -21

Rear Tyre

140/80 -18


Length: 2180 mm / 85.8 in

Width:     807 mm / 31.8 in

Height:  1270 mm / 50.0 in


1490 mm / 58.7 in

Seat Height

940 mm / 37.0

Ground Clearance

320 mm / 12.6 in

Footrest Height

413 mm / 16.3 in

Dry Weight

114 kg  /  251 lb

Fuel Capacity 

8.4 L / 2.2 US gal

Fuel Reserve

1.5 L / 0.4 US gal

The RR Enduro 4T 2015 range evolves with updates to all models of the “RR 4T Factory MY14” version and the introduction of many new technical features. The main objectives during development were to make the bike lighter and easier to control, and improve overall handling making it more enjoyable and easier to ride and, above all, more effective. The engine-block components have been made lighter and redesigned to reduce the inertial masses, and the engine sizes have been reduced to make handling easier and minimise weight. Compared with the larger capacity of the previous model, the absolute power and torque figures remain unchanged thanks to a new camshaft profile and a new exhaust system; in addition, a better distribution of the torque curve has been obtained to get more out of the engines.

The main innovation of the RR Enduro 4T 2015 range is the electronic injection system mounted on the 350 model. The system was developed together with Synerject and has a 42 mm-diameter throttle body. Electronic injection ensures precise carburation control under all usage conditions, the air-petrol mix is optimised for any altitude thanks to a temperature and pressure gauge. The engine offers immediate and smooth response with any driving style. Also, thanks to the adoption of a stepper motor mounted on the throttle body, an accurate minimum rotation speed and a reduced engine braking are always guaranteed.

The whole range is equipped with engines that have been completely renewed, both in terms of looks and performance. The total weight has been reduced by 1kg on the 430 and 480 engines, compared with the previous 450 and 498, and by as much as 1.5kg for the 350 (derived directly from the 2014 factory model) and the 390 (which will replace the 400). The central guards have been completely redesigned, made lighter and modified internally to house a new oil-pump drive system, which is simpler and more effective thanks to elimination of a drive gear. The flywheel chamber has been redesigned in order to minimise pumping losses, and the entire shape has been reworked thanks to the introduction of ribs that stiffen the engine block. The covers, clutch and flywheel have also been modified with a view to reducing weight and, at the same time, increasing the rigidity of the parts themselves.

The crankshafts have new shoulders and a new con rod, lighter and with optimised inertia, making the bike quicker to deliver power and more agile thanks to a reduction of the gyroscopic effect.

More specifically, the con rods are shorter and lighter, and feature a new design. The redesign is aimed at reducing the alternating masses and the size of the engines. The 390-430-480 cc engines, in fact, have the entire combustion unit positioned lower down compared to the previous models. This means that masses are more compact and closer to the centre of gravity, significantly improving the bike’s agility.
The piston is lighter and more robust, thanks to a structure derived from Formula 1 called “box-in-box”, which enables a reduction in vibrations and an increase in performance. The gudgeon pin is coated with a Diamond-Like-Carbon (DLC) treatment to minimise friction and wear.

The camshafts were developed with a new profile to boost performance, especially at low speeds, and to provide greater linearity of output. On the 350 and 390 version has been adopted a complete set of titanium valves.

The cylinder features a new design for the water jacket to improve the removal of heat and increase the efficiency of the whole cooling system. The head has been completely redesigned both in terms of the conduits and combustion chamber, in relation to the needs of the new engine sizes, and externally.

The starter motor has been significantly improved and is more powerful and lighter compared with the previous models. The balance shaft has been completely redesigned in relation to the different balancing of the primary masses of the crankshaft unit; the result, also here, is a significant reduction in weight. The intake sleeve has been completely redesigned for the new engine sizes to guarantee better fuel supply, optimal filling of the engine and therefore a better yield, particularly at low rotation speeds.

Key features:

•Electronic Fuel Injection
•Engine from the 2014 Factory Edition
•Die-Cast Engine cases (2.2 lbs. lighter)
•Beta’s ETR(Easy-To-Ride) Engine
•New front fork compression piston to improve oil flow and reduce harshness
•New rear shock piston to reduce heat
•Handlebar pad from Race Edition
•New design seat foam that is softer
•New graphics and color scheme