so i know this has been beat to death but i also realize that each bike is an individual so if anyone feels like answering me with some knowledge power it would be mucho appreciado...
   i replaced stock with a straight tip dyna muffler it has baffles and a smaller exhaust port than the tapered dynas i see on here. i pulled out the plug on the idle mix screw to try and alleviate some excessive backfiring on decel.
   i followed direction on here and turned the thing out to 6.5 turns without noticing a difference in the sound of the engine! i stopped there for fear of popping the screw out. i ended up putting it at about 3 turns out. the backfiring is not horrible but it's there.
   what am i doing wrong? do i need to rejet? would 152.5 main be the only jet i need to replace? thanks guys in my two months of owning and modding this bike(my first( you guys have been a tremendous help and inspiration!


oh yeah..and if i threw a k&n drop in filter into the mix, would 152.5 still be all i need?


i saw a cool spreadsheet here about mods and rejetting, some 4 step method, but i cant seem to find it again.

Adjust the main, based on wide open throttle performance...
...In 4th, or 5th gear at a slow cruise, open throttle to wide open for several seconds,... then back off about an 1/8 of a turn... it you notice a slight gain in momentum before decel,...... go up one step on the main, then try again...
Adjust the pilot,...one step higher, if you feel the need to open the idle mix more than 3 turns out...
Adjust the idle mix for smoothest idle and least erratic  throttle transitions...

each adjustment effects the other,... so go slowly...

Pops, blats, and wubbles,... are okay, and normal for a big thumper on decel...   gunshot "kerpow!'s" are not...
Work with idle mix, and idle speed... back and forth, to get the smoothest, on/off transitions...


PS,.. before anything,.... make sure you don't have any exhaust leaks...  leaky pipes are a wild card... they'll throw everything off...

It's weird, but some do and some don't... I've played with 5 Savages and many other bikes,.... and some react to the point of dying,.. others very subtlety... and this is the same model with the same jetting and all adjusted (for better or worse) by me...
all in all,.. I'd say... 30% react strongly to idle adjustments... 60% very barely...
Don't know why... perhaps, variations in carb castings?...

That actually sounds impossible, if you think about it...

Turn it in,... 'till you hear it react... then back it out, 'till it "unreacts"...
...then put it in the middle of those two places... ...

If that place is more than three turns out,... go one larger on the pilot jet and try again...