am I running to rich or lean?

[Honda400exadic]

I got my LRD pipe for x-mas..and Ive rode it twice..While I was riding it will sometimes back fire....also the pipe had changed colors (head pipe)...on my friends 400 EX it has stayed chrome. So i'm obviously running hot. I have a 150 jet w/ stock filter and lid is on...If I were to get a K & N...would this help?..plus I faleing plugs....(however you spell "faleing"...lol)...do I need to get a smaller jet or just a K&N?

[NeonImpact]

have you checked to see how dirty your filter is?
of course, a new filter will help, but its not all the time necessary..

from the previous posts i've read on here, it seems you may be running lean, then again prolly running too rich..

try a couple threads down from this one and see what they say about it and jetting, etc..

ill see if i can find out more for ya to help out!

[hondaracer31]

Backfiring indicates a lean condition. If it were too rich it would not be running hot, a new air cleaner will make it worse. Try removing the airbox lid, if that makes it worse you are too lean. If it's better you are too rich. I have fouled plugs from running too lean (it burns them up). Keep us posted, and good luck!

[seven]

Go up 1 or 2 sizes in the main.

[skemp]

Go to a 155 main jet, 40 pilot, get a Uni air filter, and pull your airbox lid off or drill some 1" holes in it.

[cals400ex]

i assume your running a keihin main?
whats the temp?
whats the elevation your at?
you could not only be lean on the main, but on the pilot jet/fuel skrew and/or the needle too.
adding a high flow filter or removing the lid is just going to make you leaner if you don't rejet.

[2004TRX450R]

Sounds like you are running lean. Try a 152 main and turn the fuel screw out about 1/2 to 1 turn out. You might also try putting the clip on the needle one position lower. The best way to adjust the fuel screw is to get the bike up to operateing temp and turn it in and out until you get the highest idle. Then readjust your idle. Most any chrome pipe will discolor so I wouldn't worry to much about that.

[Evan400ex]

I also have the LRD system and I had a hard time jetting my 400. I use a DJ 170 main with K&N and lid off. You might want to at least try a 160, or 165 with your set up.