My thought of the day...What is the purpose of emissions testing?
"Vehicle emissions testing is part of the State of Colorado's overall strategy to improve air quality in and around the Denver-Boulder region."
Why do they have the dyno?
"The I/M 240 test is much more effective than older technologies for identifying polluting vehicles. It tests for carbon monoxide (CO), hydrocarbons (HC) and oxides of nitrogen (NOx) during a simulated driving cycle. The vehicle is placed on a treadmill-like device, or dynamometer, and typical driving activities such as idling, cruising, acceleration and deceleration are performed while pollution is collected from the tailpipe."
We are talking PPM - Parts Per Million here. Demanding I 'rent' 33" tires to accuratly simulate real driving conditions is a disservice to the testing process. Using their own logic, I can assume it is also legal to remove all emissions equipment from my vehicle as long as I "returned to stock condition for testing".
Tires that are smaller than 17 inches or larger than 34 inches cannot be safely tested on the dynamometer.
"Only vehicles with manufacturer-equipped undersized or oversized tires that do not fit safely on the dynamometer will be authorized by the state to undergo an idle test instead of a dynamometer test. Vehicles with tires larger or smaller than original equipment that do not fit safely on the dynamometer must be returned to stock condition for testing. Vehicles with non-original undersized or oversized tires will not receive authorization from the state for an idle test."
Quotes taken directly from - http://www.aircarecolorado.com/im240tst.htm