Super Jet 760 Jetting does this sound right????

[lvnspeed]

70 piolts
137.5 mains
Not sure on the needle and spring
HI's 2 turns out
Lows's 1/2 turn out

or a suggestion
Type 4 pipe, 160 comperssion,stock carbs,riva FA's with outer wear,stock reeds,

 

[GIL]

In a perfect world the end goal is to have your carbs jetted to where your screws are somewhere between 3/4 to 1+1/4 out. That seems to be the sweet spot where the screws are actuall effective and therefore make the carbs easier to tune.

IE-if it runs great at 2 turns out on highs with the 137.5 main jets, I would install 145.0 main jets and see if that don't get your high speed screws in the 3/4 to 1 turn out range.

Does this make any sense? The screws are tapered needles and if they are too far one way or the other they reall y are not metering anything and therefore not really tuning anything, the hole is either closed or open.

 

[OCD Solutions]

It's close to what I run in my 760 but that really doesn't matter much. Every engine is a little bit different even if built identical.

Is it running good or does it have an issue?

 

[lvnspeed]

It's close to what I run in my 760 but that really doesn't matter much. Every engine is a little bit different even if built identical.

Is it running good or does it have an issue?

No its not running I have the entire ski apart and the crabs are apart I tossed the carb inturnals in a cup I have all my Jets and springs in not sure what it was this is what I ran in the 701 62t set up.

What spring should I run? I wana get this thing back together for next weekends ride at smith lake it doesnt have to be perfect just close so I ride this whoopty

 

[Waternut]

760....as in big bore 61x 760, 760 64x/62t, or what? What size carbs?

I'm currently running a 61x 760 with dual 44's and I've got 115 low jets and 130,135 high jets. I've ordered some 117.5 low jets though because I think the 115 aren't enough but it runs pretty good right now. Granted I'm running a b pipe and light porting though.

 

[lvnspeed]

In a perfect world the end goal is to have your carbs jetted to where your screws are somewhere between 3/4 to 1+1/4 out. That seems to be the sweet spot where the screws are actuall effective and therefore make the carbs easier to tune.

IE-if it runs great at 2 turns out on highs with the 137.5 main jets, I would install 145.0 main jets and see if that don't get your high speed screws in the 3/4 to 1 turn out range.

Does this make any sense? The screws are tapered needles and if they are too far one way or the other they reall y are not metering anything and therefore not really tuning anything, the hole is either closed or open.

Yes it does Gil. Thanks

 

[lvnspeed]

760....as in big bore 61x 760, 760 64x/62t, or what? What size carbs?

I'm currently running a 61x 760 with dual 44's and I've got 115 low jets and 130,135 high jets. I've ordered some 117.5 low jets though because I think the 115 aren't enough but it runs pretty good right now. Granted I'm running a b pipe and light porting though.

Stock 760 motor from a couch just with a head (160 compression)and Type 4 pipe. Stock carbs

 

[OCD Solutions]

My cylinder is ported and I'm running taper bored 38mm carbs so my setup is likely a bit different but I'm running a 95 gram spring with a 2.0 NS with 75 pilots and 142.5 mains.

There was a thread floating around with tons of jetting specs to sift thru and find something close to your setup. That's what I did and I haven't touched it yet.

 

[Sospikey]

FP recommends 140 high, 75 low for the type 4 and 38s. I ran 137.5 and 72.5 on a 61x overbored to 760, with porting and 38s. Used 95 gr springs and 1.5 N/S. Ran ok, I blame the pipe for my "light-switch" throttle response.