In today’s age of science, now customers do a lot of checking before buying anything. And it happens more with bikes.
Even if you fall in love just by looking at the model and the glitter, you are very inquisitive about buying. Knowing everything at once, he is reluctant to buy until it matches his needs.
The interest of bikers is deeper in the case of bikes. They want to match each part of the engine at once.
Read more: 2 valve engine or 4 valve, which is better?
SOHC vs DOHC engine
A motorcycle or car engine is called a SOHC or DOHC engine based on the number of camshafts. Engines that have a camshaft are called SOHC, ie Single Overhead Camshaft. And the engines that have two camshafts are called DOHC, i.e. Dual Overhead Camshafts.
DOHC engines usually have two intake valves and two exhaust valves, i.e. four valves per cylinder, while SOHC engines have one intake valve and one exhaust valve.
But R15 SOHC engine, but 4 valves
Today I will mainly discuss about 4 valve DOHC and 2 valve SOHC engines.
Let’s start with SOHC, i.e. Single Overhead Camshaft. And DOHC, i.e. Dual Overhead Camshafts, do not know some of its features
Features and working of SOHC, Single Overhead Camshaft
It sits above the combustion chamber. The camshaft controls the opening and closing of your valves and when to open, when to close, which to open, the angle to close as well as valve timing. If the camshaft controls more than one chamber, the valve arrangement is called a valve train.
The combination of valves with the help of rocker arms, which are mounted on a separate shaft, while the consumer and exhaust valves are arranged in a V-shape. A similar system was widely used in American cars, the domestic Uzam-412 engine was popular due to its excellent cylinder bore.
Actuation of the valve using rockers, which are used by the cam on the rotating shaft, and the valves are arranged in a row;
The presence of pushers (hydraulic lifters or thrust bearings), which are located between the valve and the camshaft cam.
Features and working of DOHC, Dual Overhead Camshafts
DOHC is usually used when controlling 4 valves, it has two inlet valves, two exhaust valves, so more air will enter the fuel chamber and the engine will have more power. But if 4 valves are controlled with SOHC then the same set up will generate more power than DOHC. Since the weight of the valvetrain will be less.
Two valves per cylinder – arrangement of valves parallel to each other, one shaft on each side
Four or more valves per cylinder – valves are installed in parallel, from 4 to 2 valves in 3-cylinder engines (VAG 1.8 20V ADR engine).
Let us know some differences between 4 valve DOHC and 2 valve SOHC engines.
performance
The main difference between SOHC and DOHC engines is performance. Because two camshafts definitely produce more horsepower than a single camshaft.
Fuel efficiency
Due to the higher number of valves, DOHC engines get slightly higher mileage. Due to high performance, fuel efficiency is supposed to be low, but due to double air intake valve, the engine can take sufficient amount of air and burn fuel well. That is why mileage is also available along with performance.
Repair cost
Repair cost of DOHC engine is higher than SOHC. Because, with double camshafts and more valves, there are many small parts inside the engine to run them. Where there are more parts, the chances of parts breaking are also higher. SOHC engines have relatively fewer parts and therefore lower repair costs.
Smoothness
Of course DOHC engine gives better performance and is smoother than SOHC engine and misfires are almost non-existent. Because, DOHC can easily control the valve timing.
Both have it’s own pros and cons.
Sohc:
Uses a single shaft to drive all valves
Fewer components makes less in weight
Better torque at low to mid range RPM
Cost effective at manufacturing
Fuel efficient due to fewer parts consuming energy
Camshaft being at the center denies the ideal location for spark plugs
Dohc:
Uses two independent shafts to operate the valves
Complex design and increased production cost
Improved volumetric efficiency with better airflow
Makes the engine capable of revving up to higher RPM
Better top end torque and increased horsepower
Capable of implementing efficiency enhancing technologies like VVT
Conclusion
Hopefully today your SOHC, ie Single Overhead Camshaft. And I have made you clear about DOHC, i.e. Dual Overhead Camshafts.
If there is any mistake in the writing, or to know any new information, you can write in the comment box.