Back firing

[kilkercal615]

I have a 2003 Yamaha SXR 600 triple that is back firing a lot when it is at like 3000-4000 rpm's. I have about 150 miles on it so far this year and it ran great. I did not pull the carbs off and clean them in the begining of the season. Do you think the carbs could be dirty or is there is a chance it is running rich. any in put is much appreciated. Thanks

[Macgyver55]

More times than not backfiring is from a lean condition. (ie: obstructed jets)

I'd recommend cleaning the carbs before riding it anymore to prevent possible damage to the motor.

[broken_line]

yes dont ride it anymore untill you figure out whats wrong with it or you will be tosssing out some serious$$$ to fix a tripple. could have to deal with the timing. but more likely the carbs. or even the throttle safety switch not making good contact.

[jonesen]

Backfiring could be caused by water in the gas but more often than not it's an electrical issue.

[leech~~]

I have a 2003 Yamaha SXR 600 triple that is back firing a lot when it is at like 3000-4000 rpm's. I have about 150 miles on it so far this year and it ran great. I did not pull the carbs off and clean them in the begining of the season. Do you think the carbs could be dirty or is there is a chance it is running rich. any in put is much appreciated. Thanks

Is your choke coming off all the way?

[kilkercal615]

thanks for the in put guys...I am going to pull the carbs tonight and clean them up. I don't think there should be water in the gas because i ran a bottle of heet through my last tank. I will check out the choke to.

[Surface Tension]

If your using oxygenated gas you increased the amount of alcohol from 10% to ? by adding Heet.

It is not needed and not recommend to be used with oxygenated gas.

Your jetting is fine for 10% alcohol but when you increase that it will run lean.

Still you wouldn't hear the lean sneeze because of that unless there was a lack of fuel issue or water.

[311Hemi]

If your using oxygenated gas you increased the amount of alcohol from 10% to ? by adding Heet.

It is not needed and not recommend to be used with oxygenated gas.

Your jetting is fine for 10% alcohol but when you increase that it will run lean.

Still you wouldn't hear the lean sneeze because of that unless there was a lack of fuel issue or water.

I agree, I would not be putting heet into my snowmobile fuel.....especially the stuff in the yellow bottle.