i held off for a while from posting for help hoping that I could figure this out.

so gonna try to keep this simple.

bought the bike and it ran like a champ. no back fire what so ever.
silicon got into my fuel and i didn't know. bike started to run weird. then i found out i had silicon in my fuel when i drained my tank.

I have an aftermarket exhaust, forcewinder intake on my 99 R*

when i took the carb apart it had a 195 dynojet main and stock needle.
I cleaned the carb and put everything back together. still no good.

i have changed the plugs to iridium.
i just got a baron's jet kit installed today.
172.5 main
needle 4th clip.

It pulls so hard now. performing awesome. It has never ran so well but... I still have the back fire.

backfire is on decel. it freaking annoys me.

I followed the baron's instructions. 3.5 on pms and played with pms both in and out and still can't seem to get rid of the backfire. when it idles it will occasionally shoot blue flames.

i'm out of ideas. can anyone help.
i have ran out of ideas.

i was thinking about dropping my main jet down.

ais was already removed when i got it.

You might want to check for air leaks around the manifold, the cap on the intake manifold intake port, around the pipes, etc. Just some ideas to think about.

What do you mean by silicon got in the fuel? Could be a clogged pilot jet? since the AIS is removed did the cap for the manifold vacuum port fall off? Is it a backfire or decel popping? Since it ran fine before, did you do some work to bike before this started? check for air leaks at manifold to heads and carb to manifold joint.

gonna check for air leaks tomorrow with smoke test. i put a carlini gas saver chrome trimming around my fuel cap but to install it say to put silicon around the gasket. well the fuel fumes didn't let the silicon cure and when i put on the cap it pressed down on the trip and oozed the silicon into my tank. i get both popping and backfire on decel.

How did you become aware of the silicon in the tank? Did you see it depostied somewhere (i.e. fuel filter).

What jet kit are you running I'll reserve further till you answer.

surveywaters: when I took the gas cap off I would find some of the silicon all jelled up on the threads of gas cap. I would always assume but was never sure. The reason I didn't know right away was because the silicon would sit at the bottom of my tank and one day I had to switch to reserve that's when everything went wrong. When I drained my fuel into a glass jar is when I saw the silicon sitting at the bottom. It seperated from the fuel like oil and water would.

Makcap: I am currently running a Baron's jet now. I followed instructions and installed the 172.5 mainjet and 4th clip on the needle. 3.5 turns out on the pms.

My first thought is a good carb cleaning...and I'm guessing it will not be easy to get the silicone out..

Very well could be a piece of silicon got into the pilot ckt, maybe in pilot jet, or any of the internal piping for that ckt. Probably will need to pull carb and give it a good cleaning, compressed air to to blow out, might want to consider those wire pokers they use for carb cleaning to push out any blockages.

a lot of good suggestions, check them first then try this. most of the fresh air kits give you a huge main and don't bother with the pilot. the basic rule is if it pops on the way up, it's rich. if it pops on the way down its lean. simple as that. the pilot circuit is lean you have a closed throttle on decel which means the needle is cutting off main jet flow and draws mostly off the pilot. you can turn the fuel screw to about 5 turns out but you have to watch cause you start loosing spring tension at about 4. or go get a larger pilot jet. and reset your fuel screw. try it in steps. jump 3 points on the pilot jet to a 38 (a stock pilot should be a 35) you can probably start with your fuel screw around 2 turns out and adjust it in or out in quarter turn increments. also pay close attention to the amount of oil on your air cleaner has on it. the one thing that you have to remember is that you will get a pops occasionally just because its a v-twin. but if you can' find a jet locally hit me up i stock them.