Super Jet Where to start out with tuning 61x

[codybrown]

I have a 61x motor with a sbn 44 on it. OEM exhaust and a Tau Ceti F/A on it. The jets are 145m, 120p, 95 gram spring, and 2.3 N/S. Where do I start with high and low speed adjustment screws. I just rejetted it, and started with both screws out ahout a half turn. There's so much fuel pouring into the carbs that I have to remove the pulse line or it will flood out and not start. Where do I go from here?

 

[sharkcus]

Why did you rejet and why did you go with those jets? I would think with a stock exhaust on a stock motor you would want to run.....stock.

You said "There's so much fuel pouring into the carbs"
Do you have dual 44s? Or a single?

 

[codybrown]

It is a single 44 sbn with a F/A on it. It had a factory b-pipe on it that I pulled off and put the oem exhaust on it. Am I off on my jetting numbers with the F/A?

 

[Dustin Mustangs]

Do you still have the stock flame arrestor? No point in running an aftermarket one on a stock engine. Then you can set the carb to stock and be done with it. If you have no choice but to run aftermarket, start with the stock jetting and go from there. Might have to lower the pop off a bit from there or fatten up the pilot.

 

[swapmeet]

Sounds like a big N&S to me for stock. Have you read the Mikuni Carb Tuning guide?

 

[WaveDemon]

I have a 61x motor with a sbn 44 on it. OEM exhaust and a Tau Ceti F/A on it. The jets are 145m, 120p, 95 gram spring, and 2.3 N/S. Where do I start with high and low speed adjustment screws. I just rejetted it, and started with both screws out ahout a half turn. There's so much fuel pouring into the carbs that I have to remove the pulse line or it will flood out and not start. Where do I go from here?

fuel should never pour out of the carb. sounds like you have a bad n/s.


have you done a pop-off check?

 

[codybrown]

I haven't done any testing with it yet, I just tried starting it late last night after I got the carb rebuilt. I only have the F/A, it came with the ski. Would I be better off with the 1.5 N/S that was in it?

 

[WaveDemon]

I haven't done any testing with it yet, I just tried starting it late last night after I got the carb rebuilt. I only have the F/A, it came with the ski. Would I be better off with the 1.5 N/S that was in it?

you need a pop off tester and test your pop off. also look over the carb tuning database thread to look for a good starting point.

from memory, where you're starting is pretty close but I think your N/S is leaking (test pop off to find out).

you'll see most 61x jetings are usually around 115-120 low and 140-150 high with a pop off in the 12-18 range.

 

[Dustin Mustangs]

Sometimes a perfectly good needle and seat can hang open so don't just get a new one if it doesn't hold pressure.

 

[codybrown]

Well, I put the 1.5 N/S back into it, and it starts right up and free revs fine. I'm going to try and get to the water tomorrow after work.

 

[codybrown]

Got it out on the water, and with the help of Watcon's article, I got it tuned in and running great.

 

[kevbo]

The arm should be flat when installed. If it is sticking up it can hold the N/S open all the time. A 2.3 will a be a little rich with a 115g spring.