MXT Carburetor Standard 12 mm complete with manual choke compatible with Minarelli Aprilia SR 50 CPI Yamaha Aerox

The MXT Standard carburetor in 12 mm design is intended as a near-series replacement carburetor for 50 cc two-stroke setups. The version with manual choke enables cold start enrichment via a lever on the carburetor. Due to the pre-assembled jetting, the carburetor is suitable for replacement and basic adjustment.

Product features:

• Carburetor in 12 mm design
• Manual choke for cold start enrichment
• Near-series design based on common original carburetors
• Pre-assembled main jet and slow jet
• Usable with original or suitable intake manifold

Technically, the near-series design means that the carburetor is intended as a replacement solution for typical 50 cc everyday setups, while the manual choke enables cold starting without an automatic choke unit. The pre-assembled jetting provides a starting basis, but adjustments may be necessary depending on the condition of the engine and intake system to maintain a stable idle and throttle response.

Technical details:

• Type: Slide carburetor
• Nominal size: 12 mm
• Choke: manual
• Main jet: M6, 90
• Slow jet: 38 or 40

The specified jetting directly affects the mixture preparation in idle, partial load and full load range. Deviations from the serial condition, for example due to a modified air filter, wear or different engine sealing, may require an adjustment so that the engine does not run too lean or too rich.

Vehicle and model compatibility:

• Compatible with Minarelli engines
• Compatible with Aprilia SR 50 cc
• Compatible with CPI
• Compatible with Yamaha Aerox

Some models are equipped with 17.5 mm carburetors ex works. In these cases, it is necessary to check before purchase which carburetor size and which connection version are actually installed.

Assembly and application instructions:

• Mounting on existing intake and air filter connection, provided that connection dimensions match
• Route manual choke access so that it remains accessible during operation
• Adjust carburetor and check engine running after installation
• Odour formation due to production-related cleaning can occur temporarily

A clean basic setting supports a stable idle and a uniform throttle response. For operation, it is crucial that connection dimensions and intake manifold design fit and the jetting matches the actual setup, as this directly affects the operational safety and the thermal load of the engine.

Note for checking before purchase:

• Please check before purchase whether a 12 mm carburetor is provided on the vehicle or a larger version such as 17.5 mm was installed ex works. Also compare connection dimensions and intake manifold design, as the component is not vehicle-specific.

Brief info: Carburetor - Installation, adjustment & tuning

Installation: Mount carburetor without tension, check intake manifold and gaskets for air leaks, adjust throttle cable smoothly, ensure fuel supply (gasoline, oil and vacuum).

Basic setting: Mixture screw usually open 1.5 - 2.5 turns, adjust idle screw for stable idle, always tune engine warm.

Tuning:

• Main jet = full throttle / high load
• Needle position = partial load & acceleration
• Slow jet = idle & starting (usually does not need to be changed)

Control: Check spark plug image

• white = too lean
• black = too rich
• brown = optimal

Important: After changes to air filter, exhaust or cylinder, a new carburetor tuning is absolutely necessary.

About the manufacturer MXT

MXT is the powerful in-house brand of Heavy Tuned and stands for high-quality replacement and tuning parts for motorcycles, scooters and mopeds.

As a reliable alternative to OEM parts, MXT offers a wide range of cylinder kits, carburetors and crankshafts to variomatic components, fairing parts and batteries. The products convince by solid workmanship, perfect quality and a strong price-performance ratio.

Ideal for drivers who are looking for durable spare parts and tuning parts for many vehicle models.