I'm wanting to find out why it's backfiring when I let off the throttle. When I rev it up. I don't know if it's the carborator or it hasn't been re-jetted right or what. It has a D&D slip on exaust on it. I've checked the timing.

It's a '97 CBR 600 F3. Any ideas?

 

A common sign that it's running lean. Any other symptoms that we can cue in on?

 

I'll try that and see if it works. so i guess im adjusting the carbs today
I'll let you know how it goes. thanks for the help.

 

One of the most common causes of backfires is air getting into the exhaust system. This usually happens on the roll off (throttle off), cold air then gets sucked in from somewhere's.

 

You should check out the service manual for proper adjustment of the pilot screws and will need the correct wrench to get to, and adjust them. The manual has the part #