(Chinese) 2-Stroke Ban, and Do We Care?

Do you care about the 2-stroke ban?


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I think Don Grube turning people in is sour grapes.Something to think about. Don Grumpy lives in CHINA.
 
I said dislike not hate...get it right boys. ;)

2 smokers are like someone farted. :D
 
I am not the sharpest tool in the shed but when you look at the very basic, I see it like this;

To go 1000 miles at 8 Mpg takes 125 galons of gas.
To go 1000 miles at 150 Mpg takes 6.6 galons of gas.

So if you are saying that the emissions are higher out of 6.6 galons verses 125 galons, I say, it's impossible.
Doc
I didn't believe it at first either. I bought a Mitsubishi TLE-43 for my bike, in part because it's "Clean Burning." It emits just a little more than half the pollution that CARB II allows.

EPA requirements for vehicles under 8500 lbs are 3.5 g/mile, total emissions.

But, keep this in mind: CARB II small engine standards are actually VERY lax, when compared to auto emissions.

With CARB II emissions for small engines (< 65cc) the ratings are in grams per KWH. Currently, the total emissions must be less than 560 g/KWH. (Recent proposals would drop this to 536 g/HWH.)

For a 2 HP engine, pushing a bike at 20 MPH (We'll stay with the Federal motorized bike recommendations for this calc) at the CARB II emissions limit, we're looking at:

560 gr/KwH * 2 Hp * .746 KW/Hp = 836 gr/H.
836 gr per Hr / 20 M per Hr = 41.8 g/mile :cry:
That's nearly 12 times the emissions per mile of a car. If a 150 HP auto engine pumped out emissions at CARB II rates, we're talking nearly 63 Kilograms (138 pounds) per hour!

Why are CARB II emissions so high? Small engines are MUCH more difficult to apply pollution controls to (economically) than large engines. For instance, the Mitsubishi standard 2 stroke, without stratified scavenging or emissions controls, puts about 17% of the fuel straight out the exhaust pipe, without even burning it! (A two stroke with scavenging puts about 5% of the fuel out the pipe without burning it.) A standard, old-technology 2-stroke pumps out about 25% of the fuel, unburnt! This means that old technology 2 strokers at 150 mpg push out about 1.6 gallons of fuel over 1000 miles (which works out to about 4.4 grams per mile of unburnt fuel.) This doesn't even count the emissions from the fuel that was actually burned...

The unmodified two stroke engine pushes out nearly the same emissions of a car, per mile, just in unburnt fuel alone.

The reason that the 2 stroke pushes out so much unburned fuel is that, for a short time, when the exhaust and intake ports are both open, the fuel-air mix is entering the cylinder at the same time that the exhaust gasses are leaving the cylinder. A part (about 17%) of the fuel-air mix goes straight through cylinder. This is known as 'short circuiting' the cylinder. In a stratified scavenging system, a secondary air port is initially opened instead of the fuel/air port. Pure air goes into the cylinder first, and IT is what goes straight through... (Ref the Mitsubishi design white paper link, below) This reduces the short circuited fuel to about 5% of the total. (And, it makes the engine more fuel efficient.)

Now, if you refer to the Mitsubishi TLE-43 2 stroke design documentation, it runs at about 312 gr/KwH, total emissions. (It's a 'clean-burning' 2 stroke that uses a stratified scavenging design.) If you apply the same calc as above, this works out to 23.2 gr per mile. But, that is still about 6 times the pollution per mile as a car.

When you include the emissions required to produce the vehicle, things shift around a bit. The auto industry is fairly good, in efficiency, in holding down energy costs (and therefore emissions) to build a car. The last figures I remember seeing were about 15 percent. That is, the total cost of energy (and therefore emissions) was about 15 percent of the total lifetime fuel costs of the vehicle. Add in the 'hidden' fuel costs of about 10% to produce & ship fuel to the pump, this means that there's about a 25% extra cost per mile, in terms of emissions, for the auto. This means that total auto emissions are close to 5 gr/mile, or about 1/4 the emissions of my "clean burning" bike engine.

I would guess that if I added a cat-converter muffler to the mitsubishi, I could get close to automotive emission standards. And, if considering city start-stop driving patterns, I could probably exceed emissions for an auto, since a bike spend a proportionally greater percentage of its time 'at speed'. But, a motor that just meets CARBII standards can't even come close. Let alone ones that didn't even meet CARB II.

Ref Energy Costs for Auto Lifetime
 
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I posted this once before, might be in the early part of this thread.

http://www.greenermiami.com/greenermiami/2006/08/back_in_may_the.html

Even with figuring in fantastic MPG, the 2 smokers still pollute more. Plus these Chinese 2 smokers vent their gas tanks / carbs to the atmospher and run 28 or 32 to 1 mix. Just the facts w/o hate.

Clean burning Nipponese smokers run 50 to 1, are not vented to the atmospher and run CATs in their mufflers.
 
Thats like saying..

Look.. You guys.. You can take a barbecue grill fully loaded with Burgers and Steaks and the pollution it emits would be more than 10 Mt Saint Helens during full eruption. !!! That is.. If you equate the pollution to its size and such. That is how the math works. And no.. I am not wanting a ban on Grills unless they have Cats , back cats, and sealed lids for when you add lighter fluid. Give us a Break Already !!! Thanks...
 
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