Best 125cc engine

Types of the Best 125cc Engine

The best 125cc engine is a common entry-level engine in the motorcycle world. It is perfect for commuters and learners who want to get into two-wheeled motoring. The 125cc engines are available in two major types, which include:

• Two-Stroke Engines

  Two-stroke engines have a reputation for their raw power and high rev range. They don't need complex valve-train systems because their combustion cycle is simpler. Their combustion cycle involves three basic strokes - intake, compression, power, and exhaust. The best 125cc two-stroke engines offer explosive power delivery that many riders find exhilarating. However, controlling this power can be challenging, especially for novice riders.

  Two-stroke engines also have fewer moving parts, which makes them easier and cheaper to maintain. They tend to be lighter than their four-stroke counterparts. Unfortunately, two-stroke engines are less fuel efficient. They also produce more emissions and noise compared to four-stroke engines.

• Four-Stroke Engines

  Four-stroke engines are more popular than their two-stroke counterparts. Their popularity stems from their smooth power delivery, which makes them suitable for various riding conditions and skill levels. Four-stroke engines have four distinct strokes - intake, compression, power, and exhaust. This design allows for better torque at lower RPMs.

  Four-stroke engines are also fuel-efficient, making them ideal for long-distance commuting. Furthermore, they produce cleaner emissions and less noise compared to two-stroke engines. The catch is that four-stroke engines are slightly heavier and more mechanically complex. They also have a more complicated valve-train system, which makes them harder to maintain.

Specifications and Maintenance of Best 125cc Engine

Specifications

The best 125cc engine has specifications that meet different needs in various industries. Here are some of the specifications:

• Cylinder

  The 125cc engine has a single cylinder with a cooling system that works with air or liquid. The cylinder diameter ranges from 52-58mm, while the stroke measures 50-60mm. These features help in better combustion of gases.

• Valves and Camshaft

  Each cylinder in the 125cc engine has 2-4 valves. The camshaft of the engine is located at the top and works to open and close the valves at the right time.

• Piston and Connecting Rod

  It has a piston that weighs between 90-140g with a connecting rod that weighs about 130-180g. The piston and connecting rod work together to convert the power of combustion into mechanical energy.

• Cylinder Head and Engine Block

  The engine block and cylinder head are made from aluminum or cast iron. The cylinder head contains combustion chambers, valves, and spark plugs. It is designed to allow quick and easy removal and attachment to the engine block. The engine block houses the cylinders, crankshaft, and other internal components.

• Crankshaft and Flywheel

  It has a crankshaft that measures between 110-130mm in length. The flywheel is attached to the crankshaft and is responsible for storing and stabilizing rotational energy.

• Fuel System

  The fuel tank of the best 125cc engine has a capacity of about 5 liters. The engine uses a carburetor with a diameter of 24-28mm, and it works with unleaded gasoline with a minimum octane rating of 90.

• Lubrication System

  The engine has a capacity of 1.0-1.25 liters of oil. It uses oil with a viscosity rating of 10W-40. The oil is responsible for lubricating the moving parts of the engine to reduce wear and tear.

• Ignition System

  The 125cc engine uses a 12V battery-powered ignition system. The spark plug has a gap of 0.6-0.7mm, while the ignition timing is between 1-3 degrees before the top dead center.

• Electrical System

  The electrical system has a 12V electrical system, with an output of 60W-90W from the alternator. It has a starter motor with a power of 0.8-1.2 kW, and the engine has a compression ratio of 9:1 to 11:1.

Maintenance

Here are some maintenance practices for the best 125cc engine:

• Oil Change: The 125cc engine's oil should be changed after every 3000-5000 km. The oil keeps the moving parts lubricated and reduces friction. This helps to ensure the engine runs smoothly and efficiently.
• Air Filter Replacement: The air filter of the 125cc engine should be changed every 10000 km or after one year, whichever comes first. The air filter prevents dirt and debris from getting into the engine. This ensures the engine has clean air for combustion, thus improving performance.
• Valve Clearance Check: The valve clearance should be checked every 5000 km. This ensures there is the right distance between the engine's valves and the valve lifters. The correct distance makes sure the valves open and close properly, thus preventing damage to the engine.
• Spark Plug Inspection: The spark plug should be inspected every 10000 km. The inspection helps to ensure that it is firing correctly. This ensures the engine has a spark for combustion.
• Fuel System Cleaning: The fuel system of the 125cc engine should be cleaned every 20000 km. Cleaning the fuel system helps to remove any build-up of dirt or debris. This ensures the engine gets the right amount of fuel for optimal performance.
• Cooling System Check: The cooling system should be inspected every 10000 km. This practice ensures the engine's cooling system is working effectively. It prevents overheating of the engine.

How to choose the best 125cc engine

Choosing the best 125cc engine requires careful consideration of several factors that align with specific needs and preferences. Here are some key points to keep in mind:

• Purpose: Consider the intended use of the vehicle with a 125cc engine. For urban commuting and short-distance travel, a smooth and fuel-efficient engine is ideal. If the engine is for off-road adventures or highway cruising, a more robust engine with better torque and power delivery may be necessary.
• Brand Reputation: Look for well-established brands with a good reputation for producing reliable and durable engines. Reading reviews and seeking recommendations from experienced users can provide valuable insights into the engine's performance and longevity.
• Fuel Efficiency: 125cc engines are known for their fuel efficiency, but some variations offer better mileage than others. If fuel economy is a significant concern, prioritize engines explicitly designed for fuel efficiency.
• Maintenance and Serviceability: Consider the ease of maintenance and availability of spare parts for the chosen engine. Regular maintenance is crucial for engine longevity, so selecting an engine with accessible components and a widespread service network can save time and money in the long run.
• Power Delivery and Performance: While all 125cc engines have similar displacements, power delivery and performance can vary. Some engines focus on smooth power delivery for city riding, while others offer peaky power for sporty performance. Test riding or researching performance characteristics can help find an engine that matches the desired riding style.
• Emissions and Environmental Impact: With growing concerns about emissions and environmental sustainability, considering the engine's emissions standards and environmental impact is essential. Some modern 125cc engines incorporate eco-friendly technologies to reduce emissions and fuel consumption.

How to diy and replace best 125cc engine

Some 125cc motorcycle engines are easy to work with, and some aren't. When working with an easy-to-work engine, the following steps can be taken to replace it:

• Remove the seat, side panels, and gas tank.
• Unplug all the electrical connections, including the starter, alternator, and main relay.
• Use a floor jack to support the engine and loosen all the bolts holding it to the frame.
• Loosen the engine's head bolts and remove the head and cylinder.
• Remove the engine from the frame and replace it with a new one.
• Reverse the steps to complete the process.

For engines that are not easy to work with, it is advisable to seek professional help.

Q&A

Q1: Are 125cc engines good?

A1: 125cc engines are good engines for many types of vehicles. They are good for short-distance travel and commuting. However, for long-distance travel, they are not the best.

Q2: How fast can a 125cc engine go?

A2: A 125cc engine can go from 60 to 65 mph. Factors like road conditions, weather, and even the rider's weight can affect the speed.

Q3: How do I maintain a 125cc engine?

A3: Maintaining a 125cc engine is very simple. Always check and change the engine oil regularly. Also, check the air filter and spark plug to ensure they are in good condition. The final maintenance tip is to keep the fuel system clean.