Failed Emissions, Now What?

[stevec5000]

My 1100 failed the yearly emissions test, twice this time, so I can't get the license renewed this year. They require it pass HC and CO at idle and the HC (unburned hydrocarbons) was slightly too high. It has to pass with the same test results as a new bike, 5.50% CO and 1800 PPM HC but since it's not getting any younger that gets harder to do every year and mine read 2249 PPM, just a bit over. It's always hard to pass at idle since the idle mixture screws have to be adjusted just right so it's as lean as possible without missing, which is just a matter of 1/4 turn either way. If it's slightly too rich the CO will be too high but if it's slightly too lean and misses the HC will be way too high but I have always been able to get it set correct with a Color Tune and double check with an exhaust gas analyzer. There's not even a test station in my county so even though I setup the mixture just right at home the carbs don't have temperature compensation so it's usually a bit off after I drive all the way over to the test station and I might still fail the first time but after I see the test results and tweak it a bit I can usually go back the next day and pass. This time when the HC was too high I figured it must be missing slightly so I changed the plugs and reset the idle mixture screws using the Color Tune. There was no evidence of missing and it was running fine but when I went back for a second test it still failed the same as before!
My Exhaust Gas analyzer doesn't measure HC, only CO, so I'm not sure what to do at this point. The engine has 70K miles and runs fine but doesn't idle very smoothly at slow speeds but it doesn't seem to be missing either. I'm pretty sure the cam chain needs to be replaced and the valves adjusted. Also it burns a little oil, not enough to smoke or foul the plugs but the level does fall after high speed driving so it may need rings. I wonder if burning oil would make the HC level read too high? It's always burned a little oil but not at idle. Interesting the precondition run they made me do at 2500 RPMs produced an HC reading of only 500 PPM so the problem seems to be occurring only at idle. Does anyone have any experience with fixing high HC levels who could offer some advice?
If I tell them it normally idles at 2500 I don't think they would buy it.

[xschop]

High HC

a special gas mix with some ethanol and run it a little lean on the carbs before inspection....Member Hobbyman played around with this IIRC.

[stevec5000]

It's not a matter of running leaner since CO was OK, it just has to burn more completely. I was wondering if some kind of additive like ethanol or acetone might make it burn cleaner but since I can't measure HC I have no way to tell for sure.

[xschop]

oil?

How old is your oil? You could also try Changing to Full synthetic 20-50 and will help with the oil getting past the rings if they aren't to fried. Running a little on the lean side will decrease HC emissions since the petroleum you are Leaning is the source of HC....Maybe someone in the carb department can assist here....maybe Spark advance wrong?

[Crazcnuk]

Stupid part is at 1.4hp/cuin it's far more efficient than anything else on the road around you!

Are you anywhere near a place that has 'voluntary emmission testing?

I know, with hotrods, if you have a voluntary station, or state nearby, you can take it there and try different settings.

[GrandPrix46]

So 28+ years old isn't enough to be emissions exempt? That's crazy, glad TX doesn't have emissions.

[Tdog]

E-test is BS

Is there perhaps special consideration you can apply for due to the age of your bike?
Is there a big fan (not you! lol) blowing air over your engine while the test is being done?
Have your valve seals ever been replaced?
If you are running the stock airbox and breather you could try removing the breather hose from the air box and fitting an aftermarket breather filter at the engine like some custom V twins do and that would eliminate the blowby HC from re entering, however, that trick may have to be hidden well from the inspector if he knows what he's looking at.
T

[stevec5000]

Does anyone know what the vacuum advance should be for an LG? I noticed that the speed it passed at of 2500 RPMs is where the ignition advance cuts in so I checked it more closely and found the vacuum was sticking so it wasn't advancing far enough.
The manual goes to great lengths to specify 36 deg. for the centrifugal advance at 5200 RPM and even has a drawing of what it looks like but they never mention the vacuum advance at idle, which seems odd. I get 36 deg. when I rev up the engine like it specifies but the vacuum was sticking at about 16 deg. at idle. When I got it freed up it goes to about 23 deg now. I wonder if that's right?

No, 28 years isn't old enough to be exempt. I met a guy buying oil for his 1918 Harley at Walmart once and it don't have to be inspected every year but it smoked like crazy! He said he never has to drain the oil, just keeps pouring more in! LOL

[bikerphil]

vac. adv.

The vac adv shouldn't do anything at idle. Marker should read "F". Should be 36 or close to at 5200 RPM.

[Crazcnuk]

In the hotrod community many of the 500+hp cars were passing all the tests, except one, I think it was NO, but it could have been HC.

They found if they retarded the timing a few degrees, before the tests, they could pass. Somthing to do with Combustion chamber temps.

THhs is why it is handy if there is a voluntary test station nearby where you can try different things, different fuels etc.

[mro]

might try lowering the float height .5 mm or so
Problem is engine will run hotter, could burn a valve? , color pipes etc.. but might lower your readings.


mro

[HobbyMan]

Well the only thing I can think of would be to clean your carbs, valves, and exhaust. For a while I was running Toluene and xylene through my tank every once in a while. Don't put acetone in your tank, not the same stuff. If I were you, I would pull the carbs and clean them. While they are off, clean the intake valves with a toothbrush and some carb cleaner. While the bike is sitting, put some MMO into the cylinders. And clean or replace the plugs. Make sure your carbs are synced. The reason I was using toluene is that it will certainly clean your fuel system out and it Toluene and Xylene have a higher BTU rating / unit volume than regular ethonal gasoline. Do not put these chemicals in if your tank is kremed. Also, the exhaust is more dangerous than regular gasoline. One more thing, make sure your air filter is clean. If nothing works, pack your bags and move to TX. Yee haa

[Crazcnuk]

Also, look for a gas station with methanol added in.

Don't know if you have those in the U.S. but Husky and Mohawk sell it in Canada

[TopCatGr58]

Hey Steve,

A review of the manual shows that YES, the "F" mark is where it should show at idle, but that already is 10 BTDC, since the "T" mark is TDC!

Was just thinking that a stronger spark at idle might help to burn things better!? After you ride it there, perhaps a block before you get there you could take the Ballast resistor out of the loop, jumping the plug to it together so that the ignition coils would be getting their FULL 12 volts of power which would/should yield a stronger spark! The TCI does this during starting to provide a stronger spark, so for a short period 5-10 minutes, I'm pretty sure it wouldn't hurt the coils, don't think it would burn them up, and also don't think for that short period that it would damage the TCI either, and might provide that extra oomph needed to burn up those pesky HC's!?!? Remember, running at idle also barely gets the ALT kicking/charging above the 12 volts level, which can also reduce overall power to the coils, especially WITH the resistor in line!

But along with the other suggestions of cleaning the engine's internals, that a good carb cleaning, synch, and fine tuning like you do with the colortune should get it down also! I also like the use of the thicker weight oil to prevent it from slipping past the oil rings and possibly getting into the combustion chamber. Also might run some seafoam in the tank to help clean up the carbon from the inside as well cause it has similar stuff like Hobbyman suggested, the toluene/xylene. Good Luck!
T.C.

[fredintoon]

Failed Emissions, Now What?

Hi Steve,
you could move? To a place where the eco-Nazis ain't so rabid?