MRM NTX99 NB300 Pit Bike – Red

MiniRocket NTX99 NB300 – a performance-focused dirt bike with a ZONSEN NB300 engine and 26 horsepower

MiniRocket NTX99 NB300 is a full-size off-road motorcycle built for riders who want a significantly sportier vehicle than a standard pit bike. At its heart is a liquid-cooled four-stroke ZONSEN NB300 engine with a displacement of 279.6 cm³, an output of 26 horsepower and a manual 6-speed gearbox. With large 21/18" wheels, hydraulic disc brakes and fully adjustable FastACE suspension, the NTX99 is ready for more demanding tracks, woodland trails, training and serious off-road riding.

This model follows a pure racing philosophy – minimal frills, maximum function. You will not find unnecessary road equipment here, but components that make sense off-road: a durable frame, a powerful engine, quality suspension, CNC-machined aluminium parts, handguards, an hour meter, USB sockets and guards for key parts of the bike.

Who is the MiniRocket NTX99 NB300 designed for?

The MiniRocket NTX99 NB300 is a large dirt bike for teenage and adult riders, approximately 180 cm tall and above. With a seat height of around 950 mm and 21/18" wheels, it has a full-size feel and offers much more room, stability and confidence than smaller pit bike models.

The bike is intended for riding away from public roads – on private land, tracks and in off-road environments. It is not intended for use on public roads.

ZONSEN NB300 engine – a powerful liquid-cooled four-stroke

At the heart of the bike is a single-cylinder four-stroke ZONSEN NB300 engine with a displacement of 279.6 cm³. The engine features a four-valve cylinder head and a balancer shaft, which helps it run more smoothly and reduces vibration. Its 26 horsepower output gives the bike plenty of power for brisk off-road riding, climbs, straights and technical sections.

A major advantage is liquid cooling, which helps the engine maintain a more stable operating temperature even during longer, more demanding rides. Fuel mixture preparation is handled by a quality NIBBI Racing PWK34 Black carburettor, popular among off-road riders for its quick throttle response and good scope for adjustment.

Manual 6-speed gearbox

The MiniRocket NTX99 NB300 is equipped with a manual 6-speed gearbox, allowing you to control power delivery precisely to suit the terrain. Lower gears are useful in technical sections and on climbs, while higher gears suit faster riding on more open tracks. Power is transmitted to the rear wheel by chain drive.

Adjustable FastACE suspension

The suspension is one of this model's key strengths. At the front are FastACE USD upside-down forks. At the rear is a centrally mounted FastACE monoshock. Both front and rear suspension characteristics can be adjusted, allowing you to tailor the bike more closely to your riding style, rider weight and terrain.

The quality FastACE suspension helps the bike cope better with bumps, landings, rutted tracks and faster off-road riding. Its adjustability lets you fine-tune the bike depending on whether you prefer a more comfortable feel or a firmer, sportier setup for more aggressive riding.

21/18" wheels and durable off-road tyres

The bike uses the classic full-size off-road wheel combination of 21" at the front and 18" at the rear. This combination improves its ability to tackle terrain, hold a stable line and roll over bumps. The aluminium rims are reinforced and fitted with features that improve reliability when riding at low tyre pressures and on demanding surfaces.

The off-road tread is designed for riding on dirt, gravel, mud and unsurfaced tracks. The front wheel helps you hold a precise line, while the rear tyre transfers engine power to the ground.

Hydraulic disc brakes

Braking is handled by hydraulic disc brakes at the front and rear. The hydraulic system offers better modulation and more assured braking than standard mechanical brakes. The bike is fitted with modern brake discs inspired by performance off-road motorcycles.

A practical detail is the folding brake and clutch levers, which can pivot in several directions in a fall. This reduces the risk of them snapping if the bike is dropped or makes contact with an obstacle.

Durable frame and protective components

The bike is built around a strong steel frame designed for a load of around 130 kg. The frame has plastic guards in areas exposed to wear from boots or contact with the terrain. A bash plate beneath the engine helps protect the underside of the bike when crossing rocks, roots and other obstacles.

There is also a front brake disc guard, an aluminium rear disc guard, a front sprocket cover and a practical recovery strap for pulling the bike out of difficult terrain.

Boost Parts CNC aluminium components

The NTX99 NB300 uses a range of aluminium and CNC-machined components. These parts help reduce weight, improve durability and give the bike a distinctly sporty look. Key features include aluminium handlebars, aluminium fork yokes, CNC-machined footpegs, an aluminium side stand, an aluminium rear swingarm, an aluminium folding gear lever and other details.

The CNC-machined footpegs have a sharp, non-slip profile to keep your boots firmly in place, even in mud or during more aggressive riding while standing up.

Ergonomics and equipment

The long seat makes it easy to shift your body weight when cornering, climbing and braking. The rider can move forwards or backwards easily to suit the situation. Handguards protect your hands from branches, flying stones and minor falls.

The equipment includes an hour meter, which is very useful for tracking service intervals. The bike also has USB sockets: 1x USB-A and 1x USB-C, which can be used to charge a camera, phone or navigation device during an off-road trip.

Key benefits of the MiniRocket NTX99 NB300

• Liquid-cooled ZONSEN NB300 engine with a displacement of 279.6 cm³
• 26 horsepower output
• Four-stroke single-cylinder engine with a four-valve cylinder head
• Balancer shaft for smoother engine running
• Electric starter
• Manual 6-speed gearbox
• NIBBI Racing PWK34 Black carburettor
• Adjustable FastACE suspension at the front and rear
• FastACE USD front forks
• Hydraulic disc brakes at the front and rear
• 21/18" wheels with off-road tyres
• Durable steel frame with a load capacity of around 130 kg
• Aluminium rear swingarm
• Aluminium rims and other lightweight components
• CNC-machined aluminium footpegs, gear lever, fork yokes and other parts
• Folding clutch and front brake levers
• Engine bash plate
• Brake disc and front sprocket guards
• Handguards
• Hour meter
• USB-A and USB-C sockets
• Sports exhaust with a stainless steel silencer
• Gold O-Ring chain
• Recovery strap for pulling the bike out of difficult terrain

Technical specifications

Equipment and components

• Coolant radiator
• NIBBI PWK34 Black CNC carburettor
• Adjustable FastACE front suspension
• Adjustable FastACE rear suspension
• USB sockets: 1x USB-A and 1x USB-C
• Exhaust system with a stainless steel silencer
• Plastic engine guard
• Motorcycle recovery strap
• Front brake disc guard
• Gold O-Ring chain
• Engine bash plate
• Rear shock linkage
• Engine balancer shaft
• Aluminium handlebars
• Aluminium rims
• CNC-machined aluminium footpegs
• CNC-machined aluminium fork yokes
• CNC-machined aluminium side stand
• Aluminium rear brake disc guard
• Aluminium rear swingarm
• CNC-machined aluminium folding gear lever
• Aluminium front sprocket guard
• Aluminium oil dipstick and oil filler cap
• Aluminium chain adjusters
• Folding clutch and front brake levers
• Aluminium spoke nipples
• Aluminium tyre valve
• Rim lock to prevent inner tube slippage

Summary

MiniRocket NTX99 NB300 is a motorcycle for riders who want a powerful, well-equipped dirt bike with full-size geometry, large wheels and higher-quality components. It offers a powerful liquid-cooled ZONSEN NB300 engine, a 6-speed manual gearbox, adjustable FastACE suspension, hydraulic brakes, 21/18" wheels and an extensive equipment package including CNC-machined aluminium parts.

If you are looking for a vehicle for serious off-road riding that is more than just a children's or hobby toy, the MiniRocket NTX99 NB300 is exactly the kind of bike that delivers the power, stability and equipment for a proper ride off-road.