Hey all.  I got an 05 Savage that has been backfiring since the day I drove it home with 0 miles.  It's got 2200 on it now and the pipe is starting to turn a golden brown next to the head.  I'd guesstimate about 8 inches of the pipe is changing.  But the backfiring happens most any time I don't give it gas.  I get some nice shotgun sounding blasts when rolling off, some lil tiny ones when starting cold, some lil tiny (sometimes big) ones while crusing the parking lots looking for a spot, and 1 out of 3 times when killing the engine I'll get a nice whopper.  I went to the place I bought the bike from and was only able to get a 155 main jet.  Didn't have an 152.5 jets.  So I plan on changing the one jet out and shaving the spacer.  Well, I'll probably remove the spacer first and see how that goes since it's easier to go down on the size than back up.  I wouldn't have known to do all of this without this website so I thank you guys for all the help.  It is much appreciated.  

Bruce

If the Savage backfires on lean condition, why does mine backfire when it gets plenty of juice? Why do I think it runs rich? Because if I pull the throttle after some seconds of idling the exhaust pipe spits black smoke and my spark plug is black, too...

Check the exhaust to cylinder head bolts. Don't remove the white spacer - you'll be too rich. Go with 1/2 or 2/3s spacer. They are available from Suzuki in case you need another one.

Well, after much hassle with getting the carburetor back onto the bike, it's running a little better with a 155 main jet.  The 155 was the only jet the dealership had.  It still backfires like it did, but they're not nearly as strong as they were.  I'm going to wait until my buddy gets done with his girlfriend to reattempt to get at the white spacer.  I couldn't get the screws on the throttle slide cover loose on my own.  I don't have a workbench so I need an extra set of hands.  But I did do the main jet, and had no problems with the gas tank (removing or reinstalling).  I did have issues getting the carb to fit between the carb intake and exhause hoses.  But a few scrapes and scratches later it was all in place and running.  Now I just need to solder the connections on my home-made light bar and my bike will back up to par.  I have pictures of that light bar if any of you are interested.  Cost me a whopping $35 to make.  Thanks for all the advice.

You need to adjust the pilot jet adjusting screw.  The factory sets them to a very lean position, usually less than one turn out from bottom.  Back it out (counter clockwise) to about a 1.5 to 2 turns out position.  That should help.  You can go as far a 3 turns out if necessary but at that point the next larger pilot jet is really needed.   The pilot adjusting screw is on the right side and has a little brass cover plug over it from the factory.  There are posts on this site about GENTLY drilling out the plug and then using a small sheet metal screw to pull it out...without damaging the pilot screw of course.
It is the pilot jet circuit that is primarily responsible for the backfiring issue ... assuming that the exhaust system has no air leaks  of course.