Backfiring!@!@#

[JasonJ]

Hello everyone, a couple weeks ago I bought a '05 NE5 with 87 miles on it and in mint condition. the owner has two other whizzers and his wife urged him to get rid of one. after checking it out, i got it home and rode around a bit. the next day i was adjusting the idle and air intake screws and that's when the problems began. sometime during a short ride, it began backfiring and then ran very loudly. i later found out that i lost the baffle from the muffler and that made it lose back pressure. i installed a new baffle and it runs better, but still backfires. i've replaced the spark plug, but to no avail. it runs, but quite rough. Any help?

[del]

Howdy, Jason, Welcome!

I can make a guess at the first question others here will ask, so I'll ask first...

Do you know if the previous owner had done any changes to the carb or intake restrictor??

--del

[JasonJ]

not sure, i can give him a call

[bill green]

Hi jason the fact that it had low miles, it mite be it has factory jets and needle setting.Or the valves may need adjusted .006 intake , .008 exaust. Please check main jet size and needle clip setting and you altitude and repost.Is there A one inch long manifold betweem cylinder and carb.. Bill Green Vancouver Whizzer

[fsprandy]

My '05 came with a very restrictive baffle. The current baffles offer much less back pressure. If you had a restrictive baffle to start with and replaced it with a less restrictive one the change could be contributing to the backfiring.