Need help!!! I don't know whats wrong

I've been trying to get my squarenose back on the water, but I just can't get it to run right. I swapped motors a couple of weeks ago because my old 61x was worn out. The new motor 61x/62t came out of a running blaster.

The top end is brand new with some porting and it has a 5mm stroker. The only things that have change are the electronics, flywheel and pipe. It had a stock flywheel and computer, but I swapped it out with my 61x rad flywheel, 61x stator and msd enhancer. The pipe it had before was a blaster b-pipe, now it has a limited b pipe on it.

It idles fine a starts up easy, but when you hit the gas it completely bogs and wont rev up. I dont think the jetting would need to be that different because of the rad flywheel would it?

Any other ideas on what might be wrong?

The specs of the ski are
61x/62t some porting
5mm stroker
girdled head - 35cc domes
dual 46mm carbs
b-pipe
61x rad lightweight flywheel
msd enhancer
factory pipe water box
dual cooling

the jetting
130 main
115 pilot
2.5 needle and seat
95 gram spring
 
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SUPERTUNE

Race Gas Rules
Location
Clearwater Fl.
Go up 10 on the low jet and go down 10 on the main jet.
Check ignition timing with a timing light.
If you need a chart to do this email the shop, ask for a 5mm stroker chart and Chad can email you one back.
Rad and Jetinetics flywheels have been known to NOT have correct timing.
 
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you rock!!! thanks chuck

I tried those jets out and it runs so much better!

I'm not getting a lot of bottom end, but mid and top it screams. I just have the bottom screw open half a turn, should I change my water screws at all?
 

SUPERTUNE

Race Gas Rules
Location
Clearwater Fl.
Like I said before, just because the stator is set to stock timing doesn't mean that you have stock timing @ 21 degrees.
Open up the screw to at least 3/4 turn if you have a limited chamber and try 1 out turn if you have the mod chamber and see how it goes...
Depending on what pitch prop you have, you might try a bigger bored nozzle.
 

SUPERTUNE

Race Gas Rules
Location
Clearwater Fl.
When Yamaha came out with the 701 SN they have the aluminum pump nozzle, if that's what you have... you can try the 650 plastic nozzles as they are a little bigger (3mm I think, can't remember exactly)
 
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