TS250 carb sputtering

[Succubus]

I just replaced the stock 28mm carb from my '74 Suzuki TS250 with a 30mm carb. Bike runs fine at lower RPM and grabs well from the line. At higher rpm the engine sputters and loses power. I'm figuring its the main jet, but I'm unsure whether I should start trying larger or smaller jets. Since jets cost $5 to $6 each, I want to buy as few as possible. Can anyone tell me an approximate size to start with? Stock carbs ran #170-180. I don't know what size the replacement has. It was old and difficult to read the markings. Thanks in advance,

 

[Succubus]

One update... I checked again. The stock carb ran #25 pilot, #180 main. The replacement carb has #35 pilot, #190 main. I have real inconsistent power and sputtering in the upper ranges. If I run through the gears at relatively low rph I have good acceleration and torque. As soon as it starts revving higher it sputters and loses power. Suggestions anyone? It also will not rev to the highest rpm ranges.