2T vs 4T

Do you know why the MotoGP changed 500cc 2-stroke to 1000cc 4-stroke in world class event superbikes race in 1999? Have you ever wondered why there is no 2-stroke commercial car ? I mean there is .. but rare.. as I show you at the end of this post. When we talk about power, at the same displacement there is no way 4-stroke could win 2-stroke . Other word, you`re gonna get smoked. y? let`s see theortically.

2-Stroke engine:

Advantages:

• - Two-stroke engines do not have valves, simplifying their construction.
• - Two-stroke engines fire once every revolution. This gives two-stroke engines a significant power boost.
• - Two-stroke engines are lighter, and cost less to manufacture.
• - Two-stroke engines have the potential for about twice the power in the same size because there are twice as many power strokes per revolution.

Disadvantages:

• - Two-stroke engines don't live as long as four-stroke engines. The lack of a dedicated lubrication system means that the parts of a two-stroke engine wear-out faster. Two-stroke engines require a mix of oil in with the gas to lubricate the crankshaft, connecting rod and cylinder walls.
• - Two-stroke engines do not use fuel efficiently,
  
• - Two-stroke engines produce more pollution.
• -- The combustion of the oil in the gas. The oil makes all two-stroke engines smoky to some extent, and a badly worn two-stroke engine can emit more oily smoke.
• -- Each time a new mix of air/fuel is loaded into the combustion chamber, part of it leaks out through the exhaust port.

let`s see the advantages 2-stroke over 4-stroke

• When the engine is revving at 10000rpm the 2-stroke engine ignites gasses 10000 times per minute while 4-stroke engines ignite only half. So it should have twice as much power, right?
• The 2-stroke engine does have channels for air transport but the piston opens and closes the channels, in a 4-stroke engine there are separate valves and a camshaft that do this. This means extra moving parts and a far more difficult cylinder head design. Because of this maintenance is more difficult.
• 2-stroke engines give more power. At 50cc races 2-stroke bikes can reach speeds of over 130km/h while 4-stroke bikes can hardly reach those speeds with 70cc!! The same applies to everyday use. When you remove some restrictors from a scooter it will go 80km/h. You won't reach these speeds with you're 4-stroke bike by just removing some restrictors.

So, what about advantages 4-stroke over 2-stroke?

• what does a stock 2-stroke bike use? About 1 liter fuel per 35km. What does a stock 4-stroke bike use? About 1 liter fuel per 50km!

• 2-stroke bikes burn oil. All it does is clogg up the exhaust and smell bad! They have to lubricate the cylinder and cylinder channels big time or the engine will be wrecked...
• 2-stroke bikes waste much more energy on heat than a 4-stroke bike does so the 4-stroke engine is much more energy efficient.
• Did you read the part on how the 2-stroke engine works?? Did you notice fresh fumes are used to push out the exhaust fumes?? Of course these two gasses will mix in that process, so or fresh fumes are pushed out too or exhaust fumes stay in, either way, it's bad and it sucks.
• Ever tried to speed up a 2-stroke bike?? So fast that it could do speeds of over 100km/h. If you have you know you have to add lots of extra oil to the fuel and even than it's a big problem to keep the engine running for let's say a couple of months without mayor engine damage, wasted cilinders and screwed up pistons. Take a 4-stroke engine on the other hand and it will keep running fine for months and months and months... without extra oil ;) The reason is that because of those channels in the cilinder it's much harder to keep it lubricated enough all the time. The 4-stroke engine doesn't have this problem because it has no channel in the cilinder.
• Because of technical aspects the 2-stroke engine can only have it's intake channel open only half as long as the 4-stroke engine...
• Listen to the sound of both engines...Doesn't need further explanation I suppose.

It`s all about power, emission, environment and efficiency. People don`t make 2-stroke car because of emission, environment and efficiency as well as MotoGP, but still 2-stroke is the best for power per displacement.
by the way, as i told you earlier, enjoy the singing 1950 2-stroke car ..