passing smog test

Not sure if is the right place but........

I have an 84XR500. I live in AZ, Phoenix area. So if I want to ride in the dirt legal like, since they are cracking down on everyone, I need to get tags and this thing pass the smog test. I ride in elevations from 1000 feet to about 6000 feet. The way the bike is set up, it performs well with in those altitudes.

It will not pass the smog test. The CO is 10.00 and must be no more than 5.10. I do not want to spend too much $$$. Will adjusting the fuel mixture do the trick. When I change the plug, it is always black, not real sooty and it does not burn oil. I really do not want to fool with the jets, I do not know what the old owner put it.


Smog test motorcycles :D:D:D

I believe motorcycles are exempted from smog testing in California and Nevada as I have bikes registered in both states at different properties. I would have thought bikes would have been smog exempt in Arizona, but I wasn't sure. Wow, what an unpleasant surprise!

I know CA is developing technology to inspect motorcycles and the projected date for this is 4/1/07, but I don't know many other details.

High CO indicates running rich, as does the plug. Jetting it better may give you a little more oomph!

What elevation is the test facility, and how do they do the test? Just holding the revs high, idle, on a dynometer?

It should run leaner the lower the altitude.

Can you cheat by taking off the air filter for the test? That should lean it out a little.

Gasohol (10% ethanol) will lean it out by 14%- can you find some gasohol nearby, or maybe enough pure ethanol to mix your own gasohol?


Inspection is at 1000 ft in Phoenix. The test is idle and just above idle then back to idle. No dyno. My airfilter is almost new and I just cleaned it. Is there an air / idle adjustment on the carbs to lean it out, or just re-jet it.

My last bike was 78 Kaw ZIR. I am just back into riding about a year ago. Feels great!!!!

There should be a low-speed fuel-mixture screw somewhere on the carb (primary carb if you have 2).

Turning it in should lean it out.

There's always giving it a deliberate vacuum leak....

Do you have a choke, or an enrichment circuit?

Whichever, make sure its disengaging all the way.

If its an enrichment circuit, remove the plunger and make sure its clean and the rubber is in good shape.


I have a choke. Turning the screw in will lean it out? I could be wrong, but would the screw allow more or less fuel in. I thought the screw was for air. Shouldn't I turn the screw out to add more air....just asking, I do appreciate the help.

I am a new again rider.

4 strokes typically have a fuel screw (located between slide and head), 2 strokes typ. have an air screw (located between slide and connection to airbox).

Not that honda couldn't have done something nutty on a model here-n-there...


I had to lean the idle to get my old XR600R thru in AZ, normally you turn the pilot screew in to lean the idle mixture, if it won't lean enough to pass you will have to go to a smaller pilot jet, good luck.

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