FMF Fatty Pipe and a Power Core Silencer along with a K&N Air Filter, am also lost in the jetting area. I am at sea level, what is standard jetting for this situation? There must be a thousand blasters with this setup... Thanks

 

The stock main jet is the standard.After making any air flow changes there really isn't any "standard" any more as it depends on the changes you've made of course, but also on your riding style plus the individual characteristics of your ride. As a starting point I'd try what the other rider suggested earlier on this forum; that is install a 250 main, see that your jet needle is in the 3rd position, and test ride & read your plug for proper jetting. You go from there, depending on the plug reading. A dark or black electrode is on the rich side, a white or grey color denotes lean, & a tan or light brown electrode & insulator indicates the proper jetting. If you need additional as to the ideal plug coloration in a correctly jetted engine, you can e-mail me for a pic .

 

Stock jetting on the 90 Blaster on was 230 and 88-89 was 220. I have a Blaster with a FMF exaust system. I was running a 200 main jet in mine and it ran great. I am also at sea level.

 

Hey Motordude,
Your Blaster is going to blow up. When you put an aftermarket pipe on a machine you richen the jetting due to increase fuel flow,you leaned it out. Your Blaster is soon to blow up. Im just trying to help you.