Hay all im new to the boards as well as motorcycles.  I purchased a some what rusty 2000 Suzuki Savage with 2500mi on it for 1000.00, i could not pass up the deal as the rust i can eventually work off.  When i bought the bike it had a whistle sound in the exhaust which eventually got to me so this past weekend i installed a baffled HD Sporty muffler welded on, at 1st it was back firing quite badly and today i noticed that the header pipe was loose so i tightend it up and it seems alot better but still as a bit of a pop when i let off the gas to shift for example.  The guy i got the muffler from on ebay basically said its a slip on and no need to adjust the carbs.  Is it somthing that i can deal with cause the popping doesnt really bother me i just dont want to kill the engine.  Any input would be apreciated.  And i have been following these boards alot since i got my Savage about 3 months ago.  Its a great online community.  I'm also sorry about my spelling, im a computer guy so im used to MS Word doing it for me