New Problem

[UKUnicorn]

Hey everyone,
So I've been tuning my ski recently

(Heres the spec list to hopefully help you get an idea of my set up:
- 2014 Polar composites Trixstar freestyle jetski
- 61x 701 150/150 comp
- Msd enhancer
- Coffman sizzler
- TRD waterbox
- Carbon reeds
- 46mm true cad design red top annular discharge carb
- 130 pilot 151.3 main 2.0 n/s 95 gram spring
- ProK air Filter
- Rhaas engine mounts
- Hooker 9/15
- New kart tank
- X metal trim
- Flow control valve
- JRE Pump Cone)
(482m above sea level)

My initial problem can be found in the thread titled "falling flst on its face" but i now have a new problem.

So Ive managed to dial it in alot closer than i was with my original setup, however i still cannot get it to go from Zero throttle to wide open, originally this would cause it to lean bog now the ski completely dies.

But if i go from Zero throttle to 3/4 open the ski performs exactly as you would expect, and seems mint

So is this because the high jet is too rich? Or do i need to go down to an 80gram popoff? As reading the mikuni manual what i think its saying is its the high screw but I just want to make sure as ive been fiddling with this for way too long.

Also if anyone knows the difference between a carb and an annular discharge carb please let me know as i have had no luck finding a difference.

Many Thanks

 

[john zigler]

By your description, it sounds to me as if you are still lean....

I do think you need to lower your pop off. What is your high speed screw set at? (IE How many turns out?) Have you tried changing it? Does it get better / worse with changes, and if so lean or rich changes?

 

[UKUnicorn]

Well ive only been playing with the low screw so far top screw it just chillen at 2 turns so i could fiddle with the low, im gonna pull the carb today change the pop off spring to an 80 and see how it does.

 

[UKUnicorn]

By your description, it sounds to me as if you are still lean....

I do think you need to lower your pop off. What is your high speed screw set at? (IE How many turns out?) Have you tried changing it? Does it get better / worse with changes, and if so lean or rich changes?

I havent tried bringing the high screw in though so maybe that's out to far as when i go from zero throttle to full it doesn't do what it did before when it was lean instead it just dies. So maybe the high screw is out to far?

 

[kevbo]

Your carb is too big for that application. Install a stock flame arrestor and open the top screw 2 turns. See how that works. I have a feeling that you will need very large main jet even with a stock flame arrestor.

 

[UKUnicorn]

Your carb is too big for that application. Install a stock flame arrestor and open the top screw 2 turns. See how that works. I have a feeling that you will need very large main jet even with a stock flame arrestor.

I'll have to find one thanks, ran a stock waterbox and a 701 industries airbox last year by previous owner and main was only a 130 and pilot 135 worked aces for him.

 

[john zigler]

Well ive only been playing with the low screw so far top screw it just chillen at 2 turns so i could fiddle with the low, im gonna pull the carb today change the pop off spring to an 80 and see how it does.

In your 1st post, you say it would run fine up to 3/4 throttle, then die at wide open throttle. 3/4 throttle to wide open is the high speed screw. "IF you are out 2+ turns on the high speed screw, you need to go up on your main jet.

 

[UKUnicorn]

Your carb is too big for that application. Install a stock flame arrestor and open the top screw 2 turns. See how that works. I have a feeling that you will need very large main jet even with a stock flame arrestor.

I'll have to find one thanks, ran a stock waterbox and a 701 industries airbox last year by previous owner and main was only a 130 and pilot 135 worked aces for him.

In your 1st post, you say it would run fine up to 3/4 throttle, then die at wide open throttle. 3/4 throttle to wide open is the high speed screw. "IF you are out 2+ turns on the high speed screw, you need to go up on your main jet.

Gotcha Ill go up one and see what it does thank you.