How environmentally friendly are two-stroke engines?

Question

I bought a 50cc moped to save on gas. i know nothing about motorized vehicles, but i was told that they give off more emmisions than cars. is this true? is there anything i can do to lower emmisions if it is? id hate to think im ruining the ozone.

Answer 1

I know its true that 2 cycle is dirtier than 4 cycle.  But I doubt very much you can compare a 50cc single cylinder dirty compared next to even a small 4cylinder like in a ford focus, to say nothing of everyone who drives a F150 "becuase I like trucks" (nothing against F150s guys, we know they have their place in the world, but we don't ALL need one).

  Just a thought though, if your you find you can make it on a moped, next vehicle maybe try an electric scooter?  Some cases they have more speed, range than a moped and electricity is cheaper than gas.  Myself I'm purchasing a 150cc scooter for commute as I'm about 10 miles to far from work for the electrics they sell now.

CS

Answer 2

It's like the difference between a mouse and an elephant.  Your 50cc mouse isn't in the same league as the elephant SUV .

Answer 3

2-stroke engines use a gasoline/oil mixture or you will ruin the engine.  They do not burn the gasoline/oil as completely as 4-stroke engines therefore unburned hydrocarbons and carbon monoxide will be more prevalent in the exhaust.

However, due to the very small size of the engine, you need something to compare it to for a true answer to this question.

Answer 4

Two strokes are dirtier than four strokes but they are alot cleaner than they were forty or even twenty years ago. They are cheaper to manufacture and have alot less moving parts. They tend to be lighter than their four stroke counterparts. I know which one I would rather have on my weed wacker or chainsaw.

Kiphyn b suggests they should be phased out by 2010 . I , for one , hope that never happens. Can you imagine the engineering needed to get a chainsaw to run on it's side, not to mention the weight of the thing. Personally , if I pass you in my two litre four stroke sedan in the pouring rain , I salute you.

Answer 5

two stroke engine is the best engine made ever and that's why racing motorcycles always used two stroke engines..about the pollution there are many things that pollute more than the two strokes but these are only the easy target..the best motorcycles in production were two stroke like RD350 RGV250Γ NSR250 TZR250 etc..never forget two stroke will be back!

Answer 6

seeing as the motor is burning a gas/oil mix..they do run dirtier than a 4 stroke engine, mixing your fuel right and making sure everything works properly on the engine is the only way to lower your emmisions, all in all if running right it's probobly still less than a car....

Answer 7

I caught my 2 stroker Hugging a tree the other day !!! Now it's out back smelling the rose's !!!

Seriously most older 2 stroke motors burn pretty dirty... However mfg's are starting to make them more efficient.

Example's CURRENT U.S. EPA RULES ON VEHICLES AND EQUIPMENT USING 2-STROKE ENGINES

SNOWMOBILES:

EPA rule reduces hydrocarbons (HC) and carbon monoxide (CO) 30% starting in 2006, and 50% in 2012. The rule allows corporate averaging, and has no cap on individual engines.

JET-SKIS AND OUTBOARD MOTORS:

EPA rule required 9-year phase-in (beginning in 1998 through 2006) of 75% reductions in nitrogen oxides and hydrocarbons from new engines. The rule allows corporate averaging, and has no cap on individual engines.

** California has adopted standards that would reduce these emissions above 90% in 2009.

LAWNMOWERS:

EPA rules has two phases: Phase 1 required a 30-35% reduction in nitrogen oxides and hydrocarbons starting in 1997. Phase 2 is a 70% reduction phased in between 2003 and 2007. Phase 2 allows corporate averaging.

** California is in the process of adopting a stricter Phase 3 set of standards.

SNOWBLOWERS:

Snowblowers are exempt from meeting the small engine nitrogen oxides and hydrocarbons under a wintertime use exemption. There is a carbon monoxide standard that is not difficult to meet for either 2-stroke or 4-stroke engines.

Could'nt find any specs on mo-peds in the short time I had, but this should help answer your question. (I caught my 2 stroker peeing on a tree and had to go out back and tell him no oil for you for three days young motor)!....Me thinks Iv'e been on here far to long today.:)

Answer 8

Yes, two stroke engines do give off more pollutants than a four stroke engine.

However, it is very likely that you already live a rather frugal lifestyle. The fact that you are using a 50cc moped indicates this to me.

Even though your two stroke engine may pollute a little more than a four stroke engine, because of your frugal lifestyle you are already polluting much less than most other people.

With your frugal lifestyle, you more than make up for the small additional pollution from your two stroke moped.

Personally I would not lose any sleep over it.

Answer 9

It really depends on what pollutant you are measuring.  A small 2 stroke produces very little CO2 emissions, because that is directly related to the amount of fuel burned.  So if it's global warming you are concerned with, the scooter is good.  A two-stroke does  burn oil along with the gasoline, so there is more smoke and particulate emissions, so in that respect, it is very much dirtier than any car, including the relatively clean Honda Civic.  Two stroke scooters are already being phased out in China, because of the excessive smoke and fumes from them.  They are being replaced with 4-stroke scooters and electric scooters.  Two stroke lawnmowers are beginning to be phased out in the United States and two stroke motorcycles haven't been made since the 1970's.  Before long, the only two stroke engines still available will be on chainsaws and weed whackers.

Answer 10

the 2 stroke engine is worst engine in the world when you compare it to anything else. It is on the short list for continued production. they are currently being produced at reduced rates and should be phased out by 2010.