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Does the US exhaust really have a cat?

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Does anybody know for sure? I haven't seen a drawing of the interior of the muffler, and you can't tell from looking in either end. And I don't see it in the service manual or in Yamaha US advertising. The US site says only this:

"Tucked-in, three-chamber muffler keeps the mass concentration up and the bike quiet."

Maybe the cat converter goes where the o2 sensor goes?

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Maybe some one who has replaced the muffler with a slip on can cut one open for us and take pictures?

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Pretty sure it does......

I took my wrx to the car wash once. The bike was stone cold, the car wash is less than 2 miles away. The water violently boiled off the lower half of the muffler, and just kind of dried up off the upper half. So the bottom half would seem to have some heat generating device........ like a cat con.

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Plus it has that "tick, tick, tick" heat thing going after you ride too...which at least to me sounds like a cat on a car....

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The emissions label says it does. Mine reads OC(oxidizing catalyst),SFI(sequential fuel injection) and PAIR(pulse air injection).

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To quote page 3-12 of the owner's manual: "This model is equipped with a catalytic converter in the exhaust system."

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The emissions label says it does. Mine reads OC(oxidizing catalyst),SFI(sequential fuel injection) and PAIR(pulse air injection).
To quote page 3-12 of the owner's manual: "This model is equipped with a catalytic converter in the exhaust system."

DugsGM, you're in CA, which is a special state:D. Where is the emissions label? I can't remember one, :D for my poor memory.

mwakey, that seems definitive. I should read the OM again, lately I have only looked at the SM.

Why would Yamaha make an exhaust with a cat but no lambda sensor? I thought that maybe they went together by market: o2 sensor=cat. no o2 sensor, no cat. I seem to recall that for a cat to work well, it needs to be around 14.7, right?

Are people messing with their cat when they put in a fuel controller and add fuel? I guess, if nothing else, it will get a lot hotter, or?🙂

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My emission label reads the same as DugsGM. My emission label is on the right hand side of the swing arm, near the front.

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i took off all the labels, and only saved one. I stuck it on the inside cover of the owner's maual. It only give the mfg date, the GVWR. GWARs, tire specs, "This vehicle complies with all safety standards..." blurb, and the serial number. I think it came from the frame just behind the steering axis.

Shame on me, I should have kept all the stickers.

My OM page 3-12 also says it has a cat. So I have to assume there is one in there.

Changes my exhaust plans. The Buell Blast exhaust doesn't have one. Nor does anything else I have been considering. And I'm kinda surprised to find that i won't go from a cat to no cat. Interesting.

So I keep the stock exhaust for now, and explore alternatives later, since this just got more complicated, and i want to ride.🙂

Thanks for the info / support, guys:applause:

/dh

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Hermit

I once went to get a motorcycle inspected by the Washington State Patrol and he had a fit because the goose neck sticker had paint on it. I scrubbed for about 20 minutes and he was able to see three of the digits, then barely let it pass at that. The number was stamped right there in the metal, but he had to see the sticker. One fun afternoon.

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One of the reasons I bought this bike was because it was "green" with FI and the catalytic converter. There has been a lot of bad PR(in our local paper "the cleanest motorcyle puts out more HC+NOx than a Hummer") on motorcycle emissions and I have tried to find the actual emission data to no avail. I called Yamaha and they said they do not publish that data. According to the somebody's sticker this thread it meets a 1.1 mg/km standard but that still doesn't tell me what it actually is. Does anybody have any data? Also is there an oxygen sensor on the US models?

thanks

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No o2 sensor on 2008 US model.

Probably the simplest way, in some locations, to get emissions data is to take it to a vehicle inspection place where emissions testing is required.

I'm slow to believe some of the printed claims of dirty motorcycles, at least for the small engines. I haven't seen it stated in quantitative terms, like you are seeking. As in the quote you give, it could be per-cc, or any other way they chose to compare. It just doesn't say.

If you know some sources for actual historical data on emissions from motorcycles, I'd love to see links.👍

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One of the reasons I bought this bike was because it was "green" with FI and the catalytic converter. There has been a lot of bad PR(in our local paper "the cleanest motorcyle puts out more HC+NOx than a Hummer")

.

.

.

I can almost gaurantee you that any 250cc single cylinder engine has GOT to be TONS cleaner than most cars exhaust right from the get-go.

I mean.... let's look at a 1.6L 4cyl vehicle. Each cylinder would be 400cc. Think about it... the spark plug is igniting far less volume (250cc vs 400cc or only 63%) than is typically found in a car cylinder.

So in effect... right-off-the-bat... you've got 37% more spark going on through-out the displacment. This would lend itself to more thorough combustion... no? AND your air intake is GOBS more efficient.. a much shorter, straighter shot, with a nicer foam filter vs. paper.

Whomever wrote that blurb was most likely referring to a multi-cylindered streetbike no doubt. 👍

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I can almost gaurantee you that any 250cc single cylinder engine has GOT to be TONS cleaner than most cars exhaust right from the get-go.

I wouldnt be so sure. Think about a 250f, that thing has wild cams and a relatively high compression ratio thats going to allow alot of unburned air/fuel mixture(hydrocarbons/HCs) to escape out of the tailpipe during low rpm conditions simply because of the rpm range that it was made to operate best in. It also has no catalytic convertor to deal with those HCs. Most cars put out close to zero HCs(measured in parts per million) during idle and cruise because the precision of the fuel metering and and the catalytic convertors.

Ive never seen any motorcycle with any device to deal with NOx(oxides of nitrogen). Cars have EGR valves and multiple bed catalytic convertors to take care of NOx emissions. Even the 250r/x that has a catalytic convertor still only has a oxidizing bed in the catalytic convertor and has no way to deal with NOx.

Now CO2(carbon dioxide, a green house gas) emissions would be a different story. Keep in mind that CO2 isnt measured in a emissions test and since it is a indication of efficeint combustion, the higher the percentage of CO2 coming out of tailpipe the better. Truthfully, all of the anti-smog regulations of the last 40 years have actually caused the percentage of CO2 out of car tailpipes to nearly double. So even if the percentage of CO2 out of a motorcycle tailpipe is less than of a car(which Im pretty sure it is) simply because of the much smaller amount of air passing through the motorcycle engine due to its much smaller displacement, the motorcycle is putting out less CO2.

So even though your statement about bikes being cleaner just due to thier size holds true in some ways, until bikes are equipped with all the emissions equipment that cars have its still very possible for a much smaller engine to be dirtier than a much larger one. Lawn mower engines have filthy emissions due to thier lack of precision fuel and spark control and you dont even want to know how dirty a 2 stroke is.

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The EPA does annual model testing and the results are available at:http://www.epa.gov/OTAQ/roadbike.htm

The following is an excerpt from the "detailed" FAQ on road bikes. They also have a dirt bike / ATV section. But on the face of it, on the basis of grams/mile, motorcycles do pollute more than cars.

Are motorcycles a less-polluting alternative to cars

and SUVs?

In fact, motorcycles produce more harmful emissions per mile than a car,

or even a large SUV. The current federal motorcycle standard for hydrocarbon

emissions is about 90 times the hydrocarbon standard for today’s

passenger cars. Although many of today’s motorcycles will actually meet

the current California standards, the California hydrocarbon standard is

still 18 to 24 times the current federal passenger car limit, depending on

the displacement of the motorcycle engine.

Beginning in 2004, all passenger cars, light trucks, and SUVs will be

required to meet even more stringent standards. When these standards

become effective, new SUVs will be meeting hydrocarbon standards

about 95 percent cleaner than today’s typical motorcycle.

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