ok i have a 84atc200x.i rebuilt the top end with a 1mm bore(stock was 65mm and now it is 66mm)and it has a uni filter and a open air box.i want a little more power but dont have the money to buy a exhaust pluss the stock one is allready to load.i was thinking off jetting the carb but dont know how much bigger i could go with out outdoing it.right now it has a 108 main jet the next 3 are 110,112,115.but the 83 200x has the 110 main jet so though that i could go a little bigger. can any body give me some ideas about how much bigger i could go.thanks

 

i just re jetted my 200x and it the same year as yours right now i have a 112 main jet and it works perfect, but i do know if you go up another jet size or two you will start running into problems and your main problem will be that for one its going to be really hard to start and then when you do get it started it will flood itself out because its getting too much fuel, but if i was you i would go from the 110 jet to the 112.

 

i was thinking about going with a 112 jet like you said but before i do it does it make a difference in performance such as more hp.

 

changing the jetting up one doesnt give you more hp at all really. the only way that you will really get more hp out of the 200x is going with a different exhaust system like the cobra,fmf,or dg exhaust and then put a k&n air filter on. but when you do these up grades you might have to change your air/fuel mixture a little bit but i dont think you will have to though.
well i hope this works for you and if you have any more questions dont hesitate to reply back with whatever you need to know.