Motorcycle emissions limits and fuel economy estimates

Discussion in 'Articles' started by xcel, Aug 3, 2008.

  1. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Insight into a bikes emissions and fuel economy estimates.

    [xfloat=left][/xfloat]Wayne Gerdes - CleanMPG - August 3, 2008

    Yamaha’s XT250 provided to CleanMPG as an introduction to the motorcycle.

    Thanks to details provided by Mike Schmitt, EPA Emission compliance officer for the Yamaha motor cycle corporation, there are some interesting aspects to bike emissions and fuel economy measurement. Bike emissions are less stringent than automobiles but are still controlled and are becoming cleaner as years go by.

    Bike Emissions

    From 2004 through 2007, all larger bike manufacturers’ average HC + NOx emissions levels across their entire model lineup could not exceed 1.4 g/km HC+NOx with any single model emitting above 2.5g/km. For 2008, bikes of all sizes will have to achieve HC+NOx levels of .8 g/km over a useful life of 5 years or 30,000 km. The bikes are driven for between 1,550 and 2,170 miles before initial testing with lab results showing even lower emissions as the bikes wear and age up to and including the 30,000 km final distance criteria.

    The current EPA Tier II/Bin 5 automobile emissions program allows just .1 g/km of HC+NOx so there is a ways to go before bikes will meet the requirements of the std. automobile. We are also speaking of only a few hundreds of thousand bikes vs. millions of automobiles with the overall impact of the lower standards haveing an effect to the local environment. With this, bikes like the XT250 will be fuel injected within 2 years to reduce their emissions even further with the larger displacement bikes receiving Catalytic converters.

    Fuel Economy Measurement

    Motorcycle fuel economy is measured on just one test. That being the EPA’s Urban Dynamometer Driving Schedule (UDDS) city test. While your car is driven on the same test cycle, it is only one of 5-tests to determine a 2008 or newer automobiles fuel economy.

    LA-4 or UDDS EPA City test cycle.​

    Just like the automobile, fuel economy is not measured by the amount of fuel consumed during the fuel economy test cycle but by the CO2 concentration in the emissions through the entire test cycle. From the CO2 concentration, a given fuel consumption can be estimated and a fuel economy rating determined.

    Another item with regards to the results of the motorcycle EPA city test… Our automobiles were given a 10% offset to better match the real fuel economy achieved by drivers from 1985 through 2007. Bikes are not. An example. On the FTP75 city test cycle, a 2004 – 2008 Toyota Prius achieves 66.6 mpg on the city test but its city FE rating as posted on the pre-08 Monroney sticker (new car Fuel Economy data sticker) was 60 mpg. A motorcycle that achieves 73 mpg like the XT250 on the same test cycle has no offset applied so unlike an automobile whose actual was reduce by 10%, a bike’s Fuel Economy rating is what it achieved on the test. No offsets are applied although if they were, the Fuel Economy rating of the XT250 would be rated at 65.7 mpg.

    What good would a Bike fuel economy and emissions article be without fuel economy ratings :)

    Fuel Economy Ratings of the entire 2008 Yamaha US model lineup

    ModelEstimated MPG (mpgUS)ModelEstimated MPG (mpgUS)ModelEstimated MPG (mpgUS)
    YJ12596 XVS110044XV1700PC39
    Last edited: May 8, 2009
  2. fireflyfarm

    fireflyfarm Well-Known Member

    A friend of mine recently bought a 2007 Suzuki GSXR1000. This is a great speed machine, one of the fastest on the market. He immediately took the exhaust off, and put a custom one on. It made the bike somewhat louder, but not obnoxious, and took 20+ pounds off. The issue, however, is this bike had a catalytic converter, which was removed with the mufflers. My dad and I were discussing this, and dad said he hopes the guy keeps the stock parts, because he may be in for a nasty shock in a few years, when emissions inspection becomes a requirement on bikes. It's coming. Bikes have been getting bigger and bigger (I rode a Triumph Rocket 3 with a 2300cc engine producing 140 BHP. By comparison, my CAR's engine is 2000cc!), and the complaints about unfairness in manufacture and testing are rolling in. There are also record numbers of motorcycles on the roads, and the impact is starting to build.
    My 2001 Triumph Sprint still has its stock exhaust- it's Stainless, looks good, and is VERY quiet, which I love!
  3. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Hi FireFlyFarm:

    ___Even if there are never any emissions inspections in PA, by removing the CAT, he increased his smog forming NOx emissions by over 900%! To lose 20 pounds from a vehicle that can already do the 0 – 60 dance in under 3 seconds, what is the point :(

    ___Good Luck

  4. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Motorcycle smog check proposed for California

    [​IMG] A 2008 study of after-market activity by the ARB found that 85% of motorcycles 280_cc and larger had modified exhausts. “Most” of those systems were illegal.

    [xfloat=left][/xfloat]Susan Carpenter – LA Times – May 3, 2009

    2009 Honda XR650L – 0 – 60 in 4 seconds and OEM emissions are well within in spec.

    Anything to reduce emissions to OEM certification is a win-win for all of us. -- Ed.

    Motorcycles account for 3.6% of registered vehicles in the state, and they make up just eight-tenths of a percent of vehicle-miles traveled, yet they account for 10% of passenger vehicles’ smog-forming emissions, according to the California Air Resources Board, which backs the measure. Although fuel-efficient bikes emit significantly less carbon dioxide per mile than cars, the ARB says they are, on average, 14 times more polluting per mile when it comes to emissions of oxides of nitrogen and hydrocarbons – smog-forming pollutants that have been shown to trigger asthma attacks and worsen respiratory and cardiac illnesses. (See above article for details).

    Introduced in late February, Senate Bill 435 targets bikes with illegally modified exhaust systems and would go into effect in 2012 if passed and signed by the governor. The measure has won support from health and environmental groups that say the move is critical to reducing the state's smog pollution. It has angered motorcycle-rights groups, dealers and manufacturers, which say it’s bad for business and an infringement of riders’ freedoms...

    “Five tons of smog out of 5,691 tons emitted daily from all statewide sources is so minuscule," said John Paliwoda, executive director of the California Motorcycle Dealers Assn. in Lake Elsinore. "Our feeling is that fewer people will want to buy motorcycles if they’d have to go through a smog check where no smog check is required right now." Already, the industry is aching from the freezing of consumer credit and plummeting personal wealth, which have led to a 30.5% decline in new motorcycle sales for the first quarter of 2009 versus the same period last year, according to the Motorcycle Industry Council...

    In pursuing bikes of 280 cc and above made in the 2000 model year and beyond, SB 435 attempts to home in on the size of motorcycle that is more likely to have a modified exhaust system, and an era of bikes equipped with catalytic converters. Motorcycles that employ catalytic converters are more reliant on them to reduce emissions and are at greater risk of becoming gross polluters when those systems are removed...

    Not all modified exhausts are illegal; some comply with the state emissions requirements that allow particular makes and models to be sold in the state. But many modified exhausts remove the bikes’ catalytic converters, causing them to emit twice the legal limit of hydrocarbons and oxides of nitrogen... [rm][/rm]
  5. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Hi All:

    ___And of course even more details regarding the SMOG forming emissions testing for bikes from the CA Senate Bill 435.
    ___Good Luck

  6. Taliesin

    Taliesin Well-Known Member

    That's been going on for ages.

    The original Geo Metro engine was 1000cc (60 cid), and the standard Harley engine of the time was 80 cid (1333 cc).
  7. Right Lane Cruiser

    Right Lane Cruiser Penguin of Notagascar

    Yeah, some lawnmowers have bigger engines than my Insight (0.9L) !
  8. PaleMelanesian

    PaleMelanesian Beat the System Staff Member

    Mine is nearly there. 781cc 24hp V-twin with 48" cutting width. Even with that machine, it takes me 5 hours to mow my 3 acres, and I have to do it weekly. During the mowing season (now :() it uses more gas than my car.
  9. psyshack

    psyshack He who posts articles

    I know for a fact motorcycles are cleaner than they have ever been. 4 stroke outboard marine power plant's have been leading the way IMHO. Maybe I'm wrong.

    Riding a one lunger does nothing for me unless it's a massive raw thumper. But a big bore stump pulling V-Twin in a alum frame with massive brakes and ditch digging torque,,, that can be fun. Or the screaming quad loafing at 6k rpm just waiting for the trigger to be pulled. That's better than sex.

    My problem concerning bikes is they never stay stock. The more fuel they drink the better.

    I know I'm sick. Deal With It :)
  10. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Hi Jeff:

    ___The 09 XR650L I rode a few weeks back with do the 0 - 60 dance in under 4 seconds. Most 600 cc crotch rocket will do the same in under 3. You have to ramp up to the ridiculous to get that kind of performance from a car.

    ___Unfortunately, bikes do emit a lot more HC and NOx then any car on the road manufactured in the last 15 + years and even with the latest bike manufacturer average at .8 g/km, your HCH-II is more than 100X's cleaner. Of course the HCH-II's emissions are so low as to be in the realm of the ridiculous as well ;)

    ___Good Luck

  11. Nomac

    Nomac New Member

    Good Luck. Admins, thank you for such informative forum
  12. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Hi Nomac:

    Welcome to CleanMPG and you are most certainly welcome!

  13. jcp123

    jcp123 Caliente!

    Can't say I like the idea of emissions standards on bikes. As it is, I would think the fuel savings alone should be reason enough for the Feds to want to promote motorcycles, not choke them with more emissions standards like they did to cars in the '70's. It also takes away one of motorcycling's intrinsic appeals: simplicity. Lastly, the cats (at least in Harleys, which is what I observe working at a Harley dealer) get bloody hot, and a lot of people will swap that stock exhaust to get rid of the heat. Some folks who otherwise wouldn't even bother investing $700 in a new exhaust will do so, just to get rid of the heat emitted by the cat. It therefore becomes something of a moot point to install a cat on a motorcycle when most people will remove them just to make it comfortable to ride. That's probably a good $200 wasted on the built-in price of the catalyst when the motorcycle was new, and another $700 down the drain for an exhaust for someone who wouldn't bother but for the cat's heat. Does forcing the first $200 to be spent, and beckoning the next $700 to be spent sound like cause to get one's feathers ruffled? It does to me - think about that happening to you in any context you wish.

    Having said that, I do think motorcycle fuel economy needs to be more uniformly measured and posted at the dealer much like cars. Getting information on motorcycle fuel economy is like pulling teeth compared to cars.
    Last edited: Sep 5, 2010
  14. alvaro84

    alvaro84 Homura-chan's selfishness

    I don't understand what's complicated in a catalytic converter. It's just there, you don't even have to touch it :confused: It doesn't have to be that bad, there are many bikes where you won't even notice the cat.

    But I totally agree that their FE should be uniformly measured and posted.
  15. jcp123

    jcp123 Caliente!

    The catalytic converter is one thing. Requiring them to meet, for instance, automobile emissions standards is quite another. We'll be seeing the myriad of emissions systems such as EGR that most if not all cars already carry. You'll just have more stuff to maintain and sift through to do other work on the bike along with a higher initial purchase price.

    Obviously, emissions are not a priority for me. But as motorcycles are more of a "lifestyle" purchase here in the United States, it would kill a whole industry (and what desperately-needed jobs it offers), IMHO, to take away motorcycling's simplicity for the sake of emissions controls. Think about all the consequences first before saying you wish to have better emissions on motorcycles.
  16. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Hi Jcp123:

    As of now, there will be no real increases in the emissions standard other than those that have already been placed on the books.

    That said, CAT's do not need to be hot as the WR and KLX or the bigger bore 800 and 1200 GS' have them yet their is no undo heat generated thanks to the standoffs and good design. We need bikes to have FI and CAT's so as to keep them off the radar. Nationwide, bikes make up just 0.4% of the VMT's yet used to output as much as 5% of all NOx and PM emissions of the light duty truck, cars and motorcycle population. This is changing quickly thanks to CAT's on the small through big bikes, not just the premium ones.

    Regarding FE standards, they are in place. All bike manufacturers have to report their bikes emissions on the FTP to the EPA and in doing so; have measured the FE via CO2 indirectly just as the auto manufacturers have done. They (Yamaha, Kawasaki and Suzuki) are posting the CAFE' city numbers that all cars are reporting under CAFE. While that makes the FE un-realistic for most, it is a comparison from brand to brand. Now if only Honda would release its numbers for all its bikes like the rest instead of its micro-scooters with the really big numbers.

    Finally, bike FE is not all that great. I have heard the 1.8L Goldwings and 990 KTM Adventures are good for just 35 mpg in the real world which makes them FSP’s in my book. A Prius or HCH-II will bust the average rider’s FE on any bike (other than the scooters) out on the highway. Allowing a bike to forgo emissions testing because they get 50 mpg on the 08 EPA city test (the WR, KLX and CRF would be rated at ~ that level) means Prius' and HI-I's, -II's, HCH-I's and -II's should not have to meet specs either. That is not going to happen.

    Good Luck

  17. jcp123

    jcp123 Caliente!

    FI is no perfect solution either; most folks I talk to with Harley Sportsters reported better FE with a carb than with EFI, and the carbs only need regular unleaded to EFI's required 91-or-better octane. Riders on Big Twin Harleys don't seem to notice a difference in mileage one way or the other; shouldn't an effective EFI get better mileage than the "lowly" carburetor? There's also the increased maintenance cost of EFI's myriad of electronic componentry. Now, that's just Harleys and I'm sure that doesn't apply across the board. But as you know I'm a carb fan, so EFI's a hard pill to swallow :D

    As far as the EPA and the EIA fuel economy numbers go, aren't bikes measured on a different test routine than cars? From the numbers I have found, the only thing more wildly inaccurate than cars' EPA numbers are those for bikes. Mine is rated 42/57, and while I have one time achieved 57mpg, it should probably be closer to 40/53 from what I've experienced. The bikes you cite are big honking bikes; most of the ones I see day to day are good for 40-45mpg, 50-55 on the highway, which is precisely what my 1200cc scooter is getting (when I'm not riding a 1,7 mile commute and dumping fuel into the motor on open loop the whole way!).

    I suppose other manufacturers have better cat designs, again I will stress that my experience comes working at a Harley dealer where I hear complaints about Harley cats at least once a day. YMMV with other makes :)

    Lastly, you say that there is nothing slated to be on the books for motorcycle emissions. While this is strictly speaking true, we are already seeing cats on motorcycles and even evaporative emissions control systems in California. Beware the slippery slope.
    Last edited: Sep 5, 2010
  18. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Hi JCP:

    The only way to meet emissions is through EFI. A carburetor is simply to sloppy a control for today’s specs. Maintenance of a bikes FI system "should" be as bulletproof as your car. Meaning you never touch it. A carburetor is always going to be played with if you do any elevation changes over ~ 4,000'. FE wise, a FI system will trounce a carb as well. The properly metered fuel is not wasting nearly as much as a blow by of raw and imprecisely measured fuel past the throttle plate with a carb.

    Same city test. Car's have the raw CAFE specs that you have to look up for both city and highway. I post them every year in the files section if you want to see the actual. The 10 Prius is rated at 70 mpg as just one example of CAFÉ’ “standards” vs. what appears on the Monroney sticker (51 city/48 highway/50 mpg combined). The FE reported on the Monroey is an amalgamation of the 5-cycle tests from the city and highway tests or the actual from the 5-cycle tests with the offsets applied. The Bikes only use the city test with no offsets applied just as was shown on the Monroney stickers prior to 1984 for cars and light duty trucks.

    Regarding evap controls, they should be on all bikes. For example, do you know a 1974 anything (name any car or truck) sitting on the side of the road not running has more emission then your 2010 anything while moving down the road? The CA emissions on the WR is simply a steel tank with a sealing cap, a charcoal canister for venting the tank and a sealed crankcase. There is nothing slippery about it other than the loss of .1 gallons of fuel tank capacity in the case of the WR.

    This is not a freedom issue but one of the air we breathe. Emissions controls are a matter of fact today and if one manufacturer cannot step up and match the specs that are given to it 5 + years in advance, it will be out of business.

    Good Luck

  19. southerncannuck

    southerncannuck Well-Known Member

    I've had quite a few bikes (12) over the years, and I would prefer to never have another carburated one again. I know how to work on them, but the problem is that you have to work on them. That's how I know how to work on them. I think that most Harley guy modify their bikes, and this is easier with a carb and no catalytic converter. If you leave it alone they will not give you any trouble. While I'm on the subject of old versus new, I don't want anymore chains either. I guess that I'm getting old.

    PS, since putting on a windscreen on the scooter, the MPGs are down.
    Last edited: Sep 5, 2010
  20. jcp123

    jcp123 Caliente!

    I do see more than a few issues in the service shop where I work with EFI-related components. Particularly, fuel pumps, throttle bodies, and that god-awful fly-by-wire throttle seem to be particularly troublesome, something carb'd bikes don't have. Once in a while we see problems with throttle position sensors and crankshaft position sensors as well (though the latter are used in conjunction with carb'd electronic ignition bikes as well). To their cradit, O2 sensors, constantly placed in one of the hottest spots in the exhaust stream seem to hold up exceptionally well, as do the ECM's, and the engine temperature sensors seem to exhibit at least average-to-above-average reliability.

    Carbureted bikes don't have these problems, since these components don't exist. Any book on failure rate analysis will tell you that EFI's more complicated architecture plus is high individual component cost almost has to be a liability. Even extremely low failure rates compound very quickly with the more parts you have in any given system. Think about a $450 gravity-fed carburetor vs. ~$200 fuel pump, $60 injectors, $50 TPS, $500 throttle body, $100 IAC valve, $400 ECM, all with their own individually compounding failure rates.

    Except for (car) Holleys and a few of the more exotic carbs (Solex, etc.), carbs are more set-it-and-forget-it than you might think. Though I don't have a carbureted bike right now, I can say in the Mustang all it takes is about 90 seconds twice a year to swap out my metering rods for summer vs. winter, and I never have to worry about its tune again. That really isn't so much work, is it?

    MPGwise, it is more-or-less taken as a fact, as I stated earlier, that carbureted (pre-2007) Harley Sportsters got marginally better FE than those with standard EFI, and that Big Twin models saw no improvement (though no decline). This is admittedly anecdotal, but comes from a lot of riders so there may be some truth in numbers. I can't know whether this is from inferior EFI design or what, but that fact remains. That aside, a well-tuned carburetor should more or less equal the FE of an EFI'd vehicle of the same specs (make, model, weight, gearing, motor size and specs, etc.). And that fact remains that the average bike will still get better FE than the average car, which I say once again should be something we should be lauding for our own national security and prosperity rather than trying to saddle with yet more regulation that's strangled so much of our economy already. People aren't going to care much about the environment until they can pay their bills.

    As for emissions, I see you feel strongly about it. I simply...don't. I save fuel to save money :)

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