Quick jetting Question

If I have a motor jetted rich with 147.5 mains in it at 1/2 a turn, and I downsize to 145 jets what would be the reccomended starting position for the screws.
Thanks
 
It is a big bore Yamaha tripple, I know I am close on the jetting I just need to know approx where to start with the screws when you downsize one jet size with the mains with the screws almost all the way in. Do I start at about 2 1/2 turns out and then 1/4 turn in at a time from there?
 

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Race Gas Rules
Location
Clearwater Fl.
Set the high speed screw at 1 1/2 turns out and run ski.
If too rich go 1/2 turn in, if still too rich, change jet by 5 go back out to 1 1/2, then repeat if needed...
 
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Thanks Chuck,
I don't know if any of you guys have worked on the GPR or not but with a single pipe on it, its next to impossible to get at the high speed screws. My arms look like I have been fighting a tiger from trying to get in there to reach them. The closer I can get them before I install the pipe the better.
Thanks Again
 
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