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I used an 6m6 case with a ported 61x cyl for a season. I exchanged the 6m6 case with a 61x. The only difference was in the required popoff, the 61x case needed the next lighter spring and thats all. Im sure that milling a manifold will make a change, Im not sure if it would be a meaningfull one.

Make sure the wrist pins are the same size. Your new pistons have bigpin style skirt.

Just install a dry pipe on a stock engine.

They changed the sxi crank part number halfway through 95, from then on part numbers are the same for 750-800.

Are you sure its rich enough at WOT? Using other peoples carb specs is inviting disaster. Make it fourcycle at full throttle and lean in from there. Your flame arrestor will play a big roll in determining the correct main jet with oversize carbs.

The total weight of a flywheel is not a very good indicator of its inertia unless its constant thickness. I would rather have one that has plenty of material around the hub.

Reducing the inlet tract will make your pilot/popoff a little richer. Difficult to measure any real performance gain.

The TDR box is a good example of how NOT to design a muffler. If you make a single chamber box it will be a bit loud. Just make sure the outlet pipe is low enough to bottom to pull water out of the box. The stock box has one divider with two small holes/tubes at the sides. I like to make mine...

What can you expect? Depends on how you use the throttle. If you tend to fan it 20 times a second (like most riders do) then a programable battery ignition will be noticable. If not then its a huge waste of money and a bit of a headache.

Tubbies pull down when they touch the water, the hull can get into an rolling oscillation at certain speeds. The square nose would hunt laterally, the fix is in adding some material to the keel ahead of the pump.

How is nitrous going to break anything in the drivetrain?

Yep, internal fillers and vents are retarded. Good thing the hood wasnt latched on.

More importanty, what are your pump specs?

If it fits a 701 then they are most likely Wetjet domes. They should be 31cc, around 170psi on a stock 61x cyl.

Listen to the exhaust note when you are just planed out, that is the pilot jet. Then slowly open the throttle and listen at the piont where the pipe surges, thats mostly the popoff. The engine should be sputtering some for best throttle response. Its is very easy to clean up the low side by...

A good redline for the Yamaha 144 pump is around 7200rpm. At low speeds the hottest 760, or bigbore for that matter, cannot pull an old 9-17 that fast. These props work very well overall, a repitched concord runs smoother and primes faster.

The 9-17 is very good with a stock cyl and B-pipe, dont waste your time cutting it back. The rev limit will need to be raised if stock ignition is used. You should be able to turn around 6800 rpm static with an 85mm nozzle. Any more load will kill acceleration.

The only bad aspect of a Superjet, to me, is their directional instability on glass smooth water at high speeds. Yamahas pump works good at low speeds where Kawasakis pump does not. If you are not into rolls and flips then it wont matter which brand you ride.

Open the top needles 3 out and start closing them 1/4 at a time until the power comes up.