Stock Needles

[FIRELS1]

How much can you shim stock needles before they stop making the engine richer? Thanks, Joey

 

[one2dmax]

The more you shim the more they will richen it. You can only shim 2 washers before you run out of room for the needle to sit correctly in the housing.

Sean

 

[FIRELS1]

Two washers, how thick?

 

[SpecOps13]

I've had 2 washers that total 0.032. I believe others have had up to 0.038 or 0.040 total.. This answer will help keep the thread active so others can give a more precise answer...

Good Luck,

 

[KJShover]

I've seen two Yamaha shims. one was .015 and the other was .020, I haven't seen any factory shims that were thicker than .020. So I would guestimate the max thickness would be .040"

I have 4 of the Yamaha .020"
Lemme know if you need them and I'll mail them off to you.

 

[dannymax]

I have mine shimmed to .038" with Mark's 4 - 2 pipes....no performance issues at all.

 

[06VMAXIMUS]

I put two washers in for a total of appx. .040/.042. You have to be careful that the needle doesn't bind when you put the plastic retention screw back in. If it binds, you will have to shim it as well. Needle should be free to "float" in the slide. There is a thread here somewhere with detailed instructions and drawings.....you can do a search for it.

 

[FIRELS1]

Thanks guys that helps a bunch!!!!