News
Single Mass Vs. Dual Mass Flywheels
By AmTech OEM / September 26, 2018
Single Mass vs. Dual Mass Flywheels
Engineered Flywheel Solutions for Modern Powertrains
A flywheel is a heavy, rotating disc bolted to the crankshaft of an engine. Its primary role is to store rotational energy, prevent engine stalling, smooth out power delivery, and provide a f
Types of Flywheels
Single Mass Flywheels
A single mass flywheel is crafted from a single, solid piece of steel or metal. With no moving parts, it offers direct contact between the clutch assembly and the engine. Key features include:
- Greater thermal and warp resistance
- Can be resurfaced for extended life
- Lower cost and faster engine response
- Ideal for racing, off-road, or applications with frequent gear changes
Consideration: Single mass flywheels can produce more noise, vibration, and harshness during operation.
Dual Mass Flywheels
A dual mass flywheel consists of two separate flywheels—one attached to the crankshaft, the other to the clutch—connected by high-strength springs. This design:
- Absorbs engine vibrations and reduces noise
- Protects the gearbox from damaging torsional spikes
- Improves fuel efficiency and driving comfort
- Commonly used in larger vehicles, diesel engines, and some petrol cars
Consideration: Dual mass flywheels are more complex and costly, cannot be resurfaced, and must be replaced entirely if worn or damaged. They are also more prone to heat-related warping if not properly matched to engine requirements1.
Applications & Industries Served
AmTech manufactures both single and dual mass flywheels for a wide range of shaft sizes and configurations. Our solutions are used across:
Our customers include multinational construction equipment companies, leading ATV manufacturers, and global powertrain OEMs.
What is the main function of a flywheel?
A flywheel stores rotational energy, smooths engine power delivery, and provides a friction surface for the clutch.
How do I choose between a single mass and dual mass flywheel?
Single mass flywheels are best for high-performance and frequent gear changes; dual mass flywheels are ideal for reducing vibration and noise in comfort-focused or high-torque vehicles.
Can a single mass flywheel be resurfaced?
Yes, single mass flywheels can be resurfaced, which extends their service life.
Can a dual mass flywheel be resurfaced?
No, dual mass flywheels cannot be resurfaced and must be replaced if worn or damaged.
What are the signs that a flywheel needs replacement?
Signs include clutch slippage, increased vibration, unusual noises, and difficulty shifting gears.
Do you manufacture custom flywheels?
Yes, AmTech offers custom flywheel design and manufacturing for unique requirements.
What materials are used for your flywheels?
We use high-grade steel, cast iron, and other alloys for durability and performance.
Can you supply starter ring gears as part of a flywheel assembly?
Absolutely. We manufacture and integrate starter ring gears for complete flywheel solutions.
Ready to discuss your flywheel or starter ring gear project? Contact AmTech International for expert support and a custom quote.