ive got a blaster that is totaly stock at the minute i would like to add v3 reeds fmf sytem and a k&n filter or uni foam what upgrades would i need to make to my carb to get the good of my upgrades currently got a stock mikuni 26ml
what size main pilot and jet needle setting?
- Thread starter simon786simon
- Start date
I'll start off simple and nice since you're new here and not jump straight in with the scolding.
First off, there are NO absolute set in stone jetting settings that work for every engine. They all vary from engine to engine, carburetor to carburetor. Luckily, there's a LOT of information out there about what other people have used in similar situations.
From experience, with those mods, you will probably need the stock pilot jet, air screw 1.5 turns out, stock needle in the 3rd position (middle), and a 290-300 main jet.
Now it's time for a little scolding. READ READ READ READ. You should go through the stickies at the top of this section and red through the jetting guides. They cover every aspect of determining not just your currently needed jetting but whether your current jetting is correct for your engine and where your jetting may need to go if you change something else
First off, there are NO absolute set in stone jetting settings that work for every engine. They all vary from engine to engine, carburetor to carburetor. Luckily, there's a LOT of information out there about what other people have used in similar situations.
From experience, with those mods, you will probably need the stock pilot jet, air screw 1.5 turns out, stock needle in the 3rd position (middle), and a 290-300 main jet.
Now it's time for a little scolding. READ READ READ READ. You should go through the stickies at the top of this section and red through the jetting guides. They cover every aspect of determining not just your currently needed jetting but whether your current jetting is correct for your engine and where your jetting may need to go if you change something else
thanks for the reply i have been reading and got abit confused because as you say everyones running different mods and stuff i was just wondering if there was anything set in stone lol all them settings you suggest im running except for the main is a 220 so for power upgrades just requires a bigger main?
Jetting sounds really confusing but it's actually REALLLLLLLYYYYYYYYYY simple (at least the theory of it is!)
Gasoline engines operate the best when the incoming fuel and air is inside of a certain mixture ratio. This is known as AFR (or air to fuel ratio) and the magic number for standard pump gasoline happens to be 14.7:1. Now in practice, 14.7:1 is too lean because a slightly richer mixture won't hurt anything but a slightly leaner mixture can burn up pistons....
The goal of jetting is to match the incoming air with the proper amount of fuel. ANYTIME you change the ability of your engine to take in more or less air, you need to match that change with a change to the fuel system (jets and needle clip position inside the carburetor).
Adding a pipe, changing air filters, removing the airbox lid, porting, head rechambering, reeds..... all change the ability of the engine to intake air which must be met with equal amounts of fuel!
Maybe you should consider changing the main jet to a #230, as #220 is a little lean for a stock setup.
