Viper Backfires...

[yamahammer viper]

My viper ran fine about a month ago but now when i start it, it backfires really loud and kills when it does.. never did anything to it... but i need help on it.

 

[Devilin AblueDress!]

My viper ran fine about a month ago but now when i start it, it backfires really loud and kills when it does.. never did anything to it... but i need help on it.

Key words "never did anything to it" I would suspect your carbs need to be cleaned. Search "backfire" many threads will pop up about dirty carbs. Either way they should be cleaned and go from there.

 

[Yaaamaaahaaa3]

While your at it you might as well clean the power valves. If the carbs are dirty, I would bet the valves are too.

 

[yamahammer viper]

While your at it you might as well clean the power valves. If the carbs are dirty, I would bet the valves are too.

i just cleaned the valves maybe a month ago, but its justt weird how a few weeks ago it ran great now i cant even give it any gas and when and if iit gets some RPMs going only two pistons are fireing i took the plugs out and cleaned them, that didnt do anything. still think its the carbs???

 

[SXlover]

Yup, definitely sounds like the carbs. My guess is the pilots are plugs. If you cleaned the valves a month ago, don't worry about them. Just clean the carbs.