backfire

[99_300ex]

Ook so I've got a 2005 r with a slip on hmf air box lid off k&n filter 13 to 1 piston and a cam. It backfires pretty bad on decel but it seems to run fine all the way up the rpm range. What should my main and pilot be or close anyways o and the fuel screw and whatever else can be adjusted. Thanks guys and gals

[bigbillg]

make sure your head pipe is tight

[99_300ex]

It's tight. It has a 195 main in it right now. Is the pilot jet what the main jet screws into?

[99_300ex]

Nvm I found the pilot its a 48. Do those two jets sound good. What should the needle be on and how is it adjusted? Anything else?

[99_300ex]

The needle is in the very middle clip also does that sound good as well as the other settings for my mods. O also the leak jet is 72. Thanks guys and gals

[99_300ex]

Someone's gotta have some input.

[chronicsmoke]

Originally posted by 99_300ex
Someone's gotta have some input.

Does it really backfire, or is it like a constant popping sound on decel?

The stock 48 pilot is a tad lean. I am switching to a 50 pilot soon because of that issue.. sometimes its worse than others, it only makes the sound during engine breaking

[400exrider707]

This needs to be fixed with the air/fuel mixture screw. It is running lean on idle, thus the pop on decel. As said, ensure the headpipe is tight, it will do the same thing if it gets loose, and they do loosen up.

Turn the idle up on the bike, adjust screw in 1/4 turn increments and wait a second for it to "catch up". Keep adjusting it until it sounds the smoothest. If you have to go more than 3 full turns out from fully seated, you need to bump pilot up one size and try again.

:cool:

[99_300ex]

Ok so just to get a better understanding of the carb I'm going to ask this. Which are each of the jets jobs and also the needle. The a/f screw is pretty obvious haha but this is the first time I have netted my self so I'm just trying to inderdtand. Thanks

[400exrider707]

http://www.howstuffworks.com/question377.htm

[99_300ex]

I know the basics but I mean like when is the main jet doing its job and when does the pilot and the leak jet. O one more thing I've read a little about the accelerator pump what does it do and how do you adjust it and why would you need to. Thanks