Super Jet Superjet tuning

[Squirrely 111]

So I just bought a 96 RN it has 48mm carbs, triton engineering head and a coffman lightning series pipe. I want to lean out the carbs so they wont suck so much gas (I am going through a half a tank in like 45 min!!) and I would like to tune the pipe so that I can get some more bottom end. Can anyone help me out?

Thank you!

 

[tor*p*do]

if you lean out the carbs, you may get detonation and ruin your motor
dual 48 will suck that kind of fuel
more info on your setup like prop, fcv, ignition, etc
would help

 

[Matt_E]

"leaning out" the carbs will not reduce your fuel consumption.

 

[eeerieski]

to reduce fuel consumption run a single 44 and lower your compression (that is if you have a high compression head on now)

 

[sj701]

that doesn't sound too far out of line. It all depends on how much throttle you are using during the ride.

 

[Squirrely 111]

if you lean out the carbs, you may get detonation and ruin your motor
dual 48 will suck that kind of fuel
more info on your setup like prop, fcv, ignition, etc
would help

Um okay well im not really sure about the prop is that what the impeller is i think its a solas impeller 14/17 (does that sound right those numbers are just popping in my head for some reason) stock ignition the compression with the head is 185 psi it has aftermarket carbon fiber reeds there's some more stuff but i'm not exactly sure what they are. I bought it used with all the parts already on it I haven't touched it since I bought it.

"leaning out" the carbs will not reduce your fuel consumption.

Oh okay I was just told that you could do that.

to reduce fuel consumption run a single 44 and lower your compression (that is if you have a high compression head on now)

um okay I don't think I want to go to a single carb but thanks for the input.

Do any of you guys have a set up that you guys like to run? As in maybe some smaller carbs and all of my buddies that I ride with have factory b's and from what they have told me is that the coffman lightning series is more for racing and has more top end from what it sounds like the factory b's have more low end and this coffman is huge!!! I would like to keep it if I can tune for a little more low end but if not I may just have to kick down some cash for a factory b.

Thanks for the help

 

[Penken]

i wouldnt lean out the carbs for it to suck less fuel.
if your ski was running fat i would lean it out. but if it´s running good i would not lean it out just to save gas. a rebuild cost more than some gas.

maybe go back to stock 38s. dual 48s should be quite big for a stock motor with just a pipe and head.

 

[piratelife]

The coffman dry pipe makes really good power for top end. you are going to need to run water injection to get any bottom end out of it. The other thing about that pipe is that it dont want to stay on it kept breaking mounts. I would start saving for a b pipe: and put this up for sale

 

[Mark44]

"leaning out" the carbs will not reduce your fuel consumption.

Umm yes it could because the motor won't be running for long. 100% fuel savings

 

[Matt_E]

Umm yes it could because the motor won't be running for long. 100% fuel savings

Lol well damn. I guess you're right. :lmao:

 

[Matt_E]

Oh okay I was just told that you could do that.

Look - the motor runs on a certain air fuel ratio. If you're off in either direction, the motor will run like crap. If your motor is running good now, then "leaning it out" will only make it run really bad and probably seize the motor.
You could put smaller dual carbs on it.

 

[augustaf]

Your ski would be a real fuel miser if you put 38 carbs on it. Regrettably, larger carbs will use a lot more gas and you cannot lean them out to control that. 1/2 tank of gas in 45 minutes is not bad at all !!!!!!! . My 46's don't do that good.

 

[bondra131]

yea prop, impeller same thing... get an Impros 10/16 hooker impeller. And if you want good bottom end power but also lots of top end, then get a Factory type 4 dry pipe and sell the lightning. The type 4 pipe hits hard at any RPM and doesnt need water injection. i am quite impressed with mine and if you want to use less gas, switch to dual 44mm carbs. thats what im running and it takes me at least an hour to burn a half tank. probably longer. and i can give you exact jetting for dual 44mm carbs with 185 psi compression and a type 4 pipe since that is my build

 

[Squirrely 111]

Alright thanks for all of the information guys I really appreciate it. I think I am going to wait to change anything on my ski until summer is over and use winter to really make my ski into how I want it to be. I will definitely be looking back to refresh my memory. Oh what are your guys opinions on hoods and footholds? I would like something that is good quality at a reasonable price thanks!