Hey! I need some help in the right direction. I have an 87 250R stock engine stock carb (155 main) K&N , FMF Fatty and an FMF Turbine Core 2. What main jet size should I be running due to the pipe and air filter? maybe a different one once the temperature gets above 15 degrees up here. I was told to bump it up to a 165 or 170.. any feedback?

 

mods are not the only thing that depends on your jets...temp and altitude play a big roll when your getting a bike. Really to find out if your jet is right you will need to ride you bike you can't just put in a jet and say oh its good because thats what a book told me. Taking off your air box lid can make things in jetting change and thats something simple. There are a few sights on the net that can tell you how to red a plut i think trinity has a pretty good one.

Rob