OPTIMASI PENYETELAN CELAH ELEKTRODA BUSI TERHADAP EMISI GAS BUANG PADA SEPEDA MOTOR MATIC

The development of the number of motorized vehicles in Indonesia is increasing rapidly each year, most motorized vehicles produce bad exhaust emissions, either due to inadequate maintenance or bad driver behavior. Air
pollution that has occurred so far is largely due to the presence of motorized vehicles as a means of transportation. Most of the air pollution is caused by motor
vehicle emissions. Motor vehicles emit harmful gases which can have a negative impact on both human health and the environment. As for the problems that occur that we often encounter, one of them is the process of replacing spark plugs where these spark plugs are part of the engine component, which if the maintenance process is ignored will have an impact on exhaust emissions, one of the causes is
the process of adjusting the spark plug electrode gap. The process of this research is to design data collection through Experiments with Optimization of Adjustment
of the spark plug electrode gap on the matic vario 125 motorcycle vehicle in 2014. Then the results of the adjustment are known to be different from the adjustment of
the spark plug gap with lower exhaust emissions of CO and HC levels. This study uses Perthalite type fuel, then adjusts the spark plug gap 0.20 mm, until the adjustment process is 1.40 mm at 900 rpm, 2000 rpm and 2100 rpm rotation, the
engine with the aim of knowing the characteristics of the exhaust gas that comes out of the vehicle into the environment . The spark plug adjustment is limited from
0.20 mm to 1.40 mm adjustment because if the spark plug setting is below 0.20 then the ignition conditions are not ideal because the spark plugs are too tight and the
vehicle is difficult to start because the CO and HC values are too large, if the setting is too tenuous then the vehicle dies quickly and the CO and CO values The HC is
too low because the fuel mixture is not ideal and the structure of the negative spark plug electrode is too backward, so the result of the sparks is not normal and not
constant. 380 ppm at 0.60 mm setting and at 2000 rpm rotation the CO value is 0.11% and the HC value is 74 ppm then at 2100 rpm the CO value is 0.15% at 0.60
mm tuning and the HC value is 78 ppm at 1.10 mm tuning. From the setting of 0.20 mm to 1.40 mm the results for CO and HC where all results are still below the threshold because for CO 5.5% and HC 4500 ppm for type 4 stroke wheeled
vehicles according to SNI regulations. So the results from the 0.20 mm setting to the 1.40 mm setting are the best at the 0.60 mm setting, the CO value is 1.77% and HC 360 ppm at 900 rpm rotation and CO 0.11% and HC 74 ppm at 2000 rpm
rotation and 2100 rpm rotation, because at 0.60 mm adjustment the ideal fuel for sparks is still constant and the flames are blue, then the gap between the positive
and negative electrodes is still a distance for normal spark plugs.

Keywords: Spark plug electrode gap adjustment, exhaust emis