125 SX ----------- Do I need jetting?

I just bought V Force3 reeds and an FMF Fatty and Shorty. Will I need to jet it? Its currently completely stock. Its an 02 KTM 125SX. How will I know if I need to jet it? Just plug color? What jets are usually needed to be changed when parts like these are added?

ANY useful information you give will be paid back, as I will add to your reputation(gas tank).



depends on what is in the carb already..previous owner may have messed with the jetting? if it is running well now,you shoukdn't have to do anything radical....maybe up one on the main and possibly clip position,keep it around 3.main 195...

Its on 3 now but i havent had any reason to check the main. When I put the pipe, silencer, and reeds on I already know its going to run completely different, so I'm wondering if the only way to tell if it needs jetting is plug color?

My sons 05 125SX came from the previous owner (in excellent condition) with a 188 / 45 combination with a works pipe and 304 silencer. He still has a little stutter in mid-range, and I'm wondering if we need to go up to 195 or there abouts too. I switched it from Motul to Motorex 2T and that helped some, mixing at 40:1.

I mix 40:1 too. The gas shouldnt have anything to do with the sputter. KTMs are ridiculous with the mid and top power, it definitely needs jetting or PV adjustment.

ED,try a 192 or a 195 ~ Phil,all that bolt on stuff is nice,but not all that radical,won't be off much jetting wise from stock,if at all.Put it on and ride,the main jet may be all you need to change.A 192 or 195 should do the trick.

Perfect. Thanks!!

i recon just chuck em on and if it coughts and splutters adjust your settings..with my bike i just slapped my fatty on and she works fine so its your call on it..

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