Post by 07jonway50 on Aug 16, 2010 0:30:14 GMT -6
I bought the 47mm bbk kit from Scrappydog. I had a mechanic Rich refered me to install it for me. My scooter is a 07 Jonway 4 stroke with 20mm carb, 88 main jet, super hot perf coil, racing cdi, iridium sparkplug, uni filter, carbon fiber exhuast, and 5gram perf rollers. Before the upgrade I got up 38 mph easily, most of the time 40. After the bbk install I test rode it right after and it topped out at 20 mph. The mechanic said it had to break in for 100 miles. It was running way rich so I down jetted to an 84. Then, same problem so down to a 75. The accel is better but it starts losing power and almost backfiring after 15 mph. Im so fed up, any help is greatly appreciated