The Effect Of The Addition of Copper DB Killer On Yamaha Vixion 150cc Motorcycle on Exhaust Emissions: Pengaruh Penambahan DB Killer Tembaga Pada Knalpot Racing Motor Yamaha Vixion 150cc Terhadap Emisi Gas Buang. PELS [Internet]. 2023 July 28 [cited 2026 Oct. 23];4. Available from: https://pels.umsida.ac.id/index.php/PELS/article/view/1423