Dual 44 Mikuni observations

[waxhead]

yes
fill in that intake crossover
i thought you had it done already

 

[Mark44]

Sorry no I have not. I will do that ASAP.

Thanks for all the help!

 

[Mark44]

d

Just got back from vacation and have a trip this weekend I will fill the cross over next week I have the Devcon from McMaster. Had to get this thread to the top as not to get lost.

I need my Brap!

Mark44

 

[Mark44]

Next week for sure had a ride last weekend and now this weekend. If Katie will let me take some time off on her ski to work on mine that is.:biggrin: j/k

Mark44 Brap!:cheer: :cheer: :cheer:
to the top

 

[felix5oh]

I've been watching you guys' thread waiting for an outcome. . . I got duel 44 problems myself. . . I just bought this ski and it's killer out of the hole but has a terrible mid range stall.

This weekend i will change the arm spring and LS jets. . . Do you mind if i chime in wit the results? . .I know it's not the same problem but i like to see what other pepole do.

here's my set up,62T:

LS-100
HS-135
NS-2.0
Spring-95 gram (around 25lbs pop off)

domed head,160 lbs compression, Cool head
Factory dry with ewci

It jumps out of the water if you feather the throtle, but if your up on a plane just cruising and go to jam on the gas it dies. . .the kid who had it before me is not a tuner and did not build it.

 

[Mark44]

I've been watching you guys' thread waiting for an outcome. . . I got duel 44 problems myself. . . I just bought this ski and it's killer out of the hole but has a terrible mid range stall.

This weekend i will change the arm spring and LS jets. . . Do you mind if i chime in wit the results? . .I know it's not the same problem but i like to see what other pepole do.

here's my set up,62T:

LS-100
HS-135
NS-2.0
Spring-95 gram (around 25lbs pop off)

domed head,160 lbs compression, Cool head
Factory dry with ewci

It jumps out of the water if you feather the throtle, but if your up on a plane just cruising and go to jam on the gas it dies. . .the kid who had it before me is not a tuner and did not build it.

Looks to me like you are too high on the high speed may want to go to 115 and up on the low possibly to 120.
Wax can get you closer than I can wait for him to chime in.

Mark44

 

[waxhead]

what type of dry pipe
can you disconect the water injection and then try it
as it makes it hard to tune with it working

 

[felix5oh]

Very well, i shall disconect the ecwi when i test ride it.

It's a Factory pipe 701 Superjet dry pipe. not the type 8.

I ordered the 102.5 and the 105's. . .Should i just go straight up to the 120's?


good luck with yours Mark.

 

[Mark44]

Very well, i shall disconect the ecwi when i test ride it.

It's a Factory pipe 701 Superjet dry pipe. not the type 8.

I ordered the 102.5 and the 105's. . .Should i just go straight up to the 120's?


good luck with yours Mark.

Thanks, still working on it but Wax has me on the correct path now. I was chasing my tail for a few months.

Wax will fix you up. :biggthumpup: :arms: :arms:

Mark44

 

[waxhead]

Can you test ride it first
I have found with the type 4 and the msd water injection it actually goes better with it turned off

I am thinking your low speed is going to end up abut 115 or 120
to go in half jet sizes is to fine at the moment i think
when you are on the plane and just cruising then you are talking low speed jet

nderstand that going up in the low speed is going to effect your top end

so its more then likely going to get worse up top while we sort out the midrange
dont worry we will get the top when we have finnished the mid

 

[felix5oh]

Wax, you rock.


Your makin alot of sense. I'll just disconect the solinoid plug from the box while testing. I changed the pop off ,too. But i'm thinking it will go back to what it was and keep trying the LS jet.

tomorrow i will test

 

[waxhead]

Great
let me know what you find and i will help to steer you in the right direction regarding your jetting

 

[felix5oh]

Just like i thought, no difference. . . When i took off the ecwi it really sounded like cr@p. . Might have been detonating right there, who knows. The plugs are light tan and the burn mark was way passed the bend telling me it's real lean. . . I parked it.


I'm just going to wait for the 120s to come in . . . . Meanwhile, i'll just ride the slow skis.

This tuning shiet takes forever but i'm sure it will be worth it when i can brapp on demand.

Stay tuned.

 

[waxhead]

Ok so you disconected the wate rinjection and the ski ran real bad
so what its telling you is the water injection is masking a severe jetting issue
Tuning a ski for peak performance takes a while but when you get it its awesome

lets go over what you have in your ski now
Its 100 low
135 high
and about 25 psi pop off

do you have a pop off gauge as you have to know exactally what it is

they have to be with in a 1lb of each other

 

[felix5oh]

it's on backorder


Thanks Wax, i'll put in the time to get it just right.

 

[robertg]

How is everyone coming along with their jetting?

I have a Superjet with a 62T 760 cylinder that I just changed over to dual OEM 44mm carbs. It has mild porting, I just widened the exhaust about 4mm, 35cc domes, MSD enhancer and a B pipe with a shortened Blaster mod chamber.

I tried 115 low, 100 high, and 15-16 psi pop off. It pulled good everywhere however it would really start running rough around 1/3 throttle. When I start off it was be smooth until 1/3 throttle, then it would start popping through the exhaust until it got on the power band. When I opened the throttle up more, it got better.

Now I am running a 105 low and 107.5 high with 17psi pop off. It has a slight lean hesitation just off idle but it is way cleaner at 1/3 throttle. It may be a little lean on top end however I just rarely open it up for more than five seconds.

I think I am going to lower my pop off to 15psi, go to a 100 low and a 115 main and see what it does.

One other problem I have is it loads up when it is tilted right and it gets lean when tilted left.

 

[Matt_E]

I recently worked my jetting over a bit.

I increased the popoff to 32 psi (from 25psi) and increased the lows from 112.5 to 115.
I also made sure to adjust my low speed screws first this time.
Once everything was right, the throttle response throughout was better.
Great now.
I still have a rich condition after landings that I can't seem to get rid of.

 

[waxhead]

worn needle and seat

 

[Mark44]

I have filled my cross over but still have not had a chance to try it out. We have trip planned for the 15th so that will probably be the test. I am on the edge of my seat here.

Mark44

 

[Matt_E]

worn needle and seat

Both of them had less than 60 hours on them. I replaced one that was suspect (very very minutely suspect) and it didn't fix the problem.
It's not the N&S.