Is my carb ok?

Fisher said

Yes go with the 650 Dbl. Ball park jetting primary 66 with a 4.5 power valve. With 74-76 jets in the rear and a plug no power valve on the secondary side. try there go out pound it hard, stop pull out #1 spark plug see how it looks, jet up or down from there.

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I agree with this except the power valve as a 4.5 is opening too late and may give him tip in issues. Use a vacuum gauge and measure vacuum at a CRUISE and take 2-3 numbers off of that and that's your PV.

If you have 18 or more inches of vacuum at cruise you will have a hard time getting a PV that opens when you want it. So you do the best you can.

I have 15 inches at a cruise and I'm using a 10.5 and probably should be a 12.5.