From the many questions and quotes we see online its clear some people may not understand the difference is between a 2-stroke and a 4-stroke engine.
Its not a matter of life or death to know or not, but it does help to be able to distinguish between the two engine types and know a little more about whats idling under your seat. So here is the simple explanation of the differences.
2-stroke engines have a power cycle every time the piston moves up and down inside the cylinder. The first stroke includes intake and compression of fuel and air which forces the fuel and air mixture up the transfer tube to the intake port and into the combustion chamber. The second stroke includes the combustion of that fuel and air and its exhaust.
The 4-stroke engine essentially follows this same process except it is taking two rotations of the crank to complete all four cycles instead of just one. The four cycles include: Intake of the fuel and air mixture on the down stroke, which opens the intake valve to let the air and fuel mixture into the combustion chamber, compression of the air and fuel mixture as the piston moves up inside the cylinder, then combustion of the mixture which forces the piston down inside the cylinder and then finally the exhaust valves are opening and the fumes are forced out of the combustion chamber on the up-stroke.
Many ATV enthusiasts remember the distinct sound of the late eighties Honda 250r ATV as it was quite possibly the hottest race ride from the nineties and on into the mid 2000 cross-country and ATV motocross scene.
The ding, ding, ding of the motor and the smell of mixed race gas coupled with awesomely explosive power was something that attracted many to the sport. Eventually though the ringing of the two banger would be replaced by the BRAAAP of the four stroke motor.
There are benefits to each of these mills and it is a hot topic in the powersports industry. At least now instead of replaying last nights episode of Duck Dynasty in your head youll be able to stay involved in the conversation next time your resident gear head starts spouting off.