750 big pin with 46 sbn carb? Does it work?

WFO Speedracer

A lifetime ban is like a lifetime warranty !
Location
Alabama
,my guy told me the 46 leans out on the high end and has seen issues because of it. The big pin (imo) needs duals. The 40i are what came on there originally and are some of the best carbs mikuni ever made. They are just hard to come by these days. Dual 44s are a pretty standard addition and can be had for about 600 bucks or so. If it were me I would be looking for 40i's.
I have modded a few sets of dual 38sbn Seadoo carbs to run on the SXR intakes, I believe they were found on Seadoo GTX and XP models with 57 engines 94-95 year models, carb spacing is slightly larger on the Kawi so the carb tie plates have to come off, you can buy the ones for the SXR or make new ones or just leave them off, I believe I slightly bent the arm on one carb and added a washer behind it to move it out some.

 

beerdart

4-Tec Jetmate
Location
CT
Im running a single 46 on 1 of my chickens 750 ported BP Coffmans pipe 180 compression I think its 135L 155H 2.0NS 22pop ill check tonight.
 
You could have some issues with your sbn 46 not related to jetting or popoff that can make it impossible to tune. My sbn 46 had a worn throttle shaft which can cause intermittent lean conditions or if the tips your adjustment screws have a low spot in the taper where they were over tightened while trying to adjust can also cause tuning issues. If there are wear marks on the screw tips, chances are the taper on the carb body itself has the same mark which isn't repairable. If you can wiggle the throttle shaft on the end where the cable goes, chances are the throttle shaft could use replacement
 
Location
dfw
I did locate this from a 750sx manual. They are calling for 75/140 jets on a cdk 40 mm, but it doesn't specifiy cdk or cdk II. Were the 750sx single carbs all small pin engines? Or did they put a single carb big pin in any skis ever?

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I never saw a stock single carb big pin engine. Every Keihin watercraft carb from 91-up is a cdk2. A stock single 40 from a 92-95 750sx work very well. The 75 pilot jet is too lean and will make the ski less reliable when cold. An 80-82 is about right depending on your pop-off spring. You can use the 140 main but that will require the top adjuster screw opened more. A 150 main gives the top screw more adjustment range.
 
I never saw a stock single carb big pin engine. Every Keihin watercraft carb from 91-up is a cdk2. A stock single 40 from a 92-95 750sx work very well. The 75 pilot jet is too lean and will make the ski less reliable when cold. An 80-82 is about right depending on your pop-off spring. You can use the 140 main but that will require the top adjuster screw opened more. A 150 main gives the top screw more adjustment range.
This is pure gold. thank you. What should I aim for regarding pop off?
 
Location
dfw
Installing a shorter spring will make idle through about 1/2 throttle richer. Re-adjusting the lower idle mixture screw may be necessary and is easy. Dont change the pilot and spring at the same time or else you will overshoot the desired setting.. Also choose a flame arrestor before you start setting the carb. I like the stock one but any will work.
 
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