asking the gurus, big khuna-fp-etc etc i know i forgotten a few ledgends

[550surf]

I would like your help as im a first timer mechanic, and i started on a modified js550 race ski.
so its been hard obtaining info as everythings mod'd so i cant turn to factory settings.

What id like is for someone whose either had experience with a similar setup as mine or just a 2 stroke ski god to help me through the challenging part of both tunning my carbs and getting the "pop off pressure" right.

please reframe from just replying, please take some time in understanding this engine setup so you can really provide information that will help. sorry but i really do need deffinate advice here as im a newbie with no experience.

the engine:

87 Pistion port engine changed to a reed induction ( the crank case has been CUT into! NOT i repeat NOT a goki adapator).

it has an ocean pro head

running dual cooling now with dual intake through the jetsport manifold

westcoast pipe

No water box, single baffle with just 40mm exhaust hose running straight out to exhasut

lighten fly wheel

total loss ignition

has a switch that operates the plugs firing

okay, so it has a dual carb setup 38mm with a single pump on the left carb
they are the older style carbs no SBN.




is there anyone out there that can give me low speed and high speed numbers aswell, as what pop off pressure do i set it at. when i first took the high and low speed pins out. i noticed the right carb, the one without the pump, has a different high and low speed adjustment, i think less turns from base.


anybody have any ideas

 

[Dartman]

always run identical carbs
use 2 carbs with pumps on them
round body carbs are very sensitive to pop off settings
must be set the same
if the carbs wont run rich at 1 1/2 turns out on the high screw you need to drill the high speed jet plug bigger

 

[kswiatk]

Considering no one else has answered, i can tell you that no one will know an exact carb setup since yours is so experimental with crankcase cutting . No one else has your setup so no one else knows any specs for it. Considering it is piped and has different flame arrestors, the pop off will need to be lowered.
You will need to tune this yourself for the most part, the BNS dont have much variability so if the setup is tuneable it will not be to hard to do.
Read some tuning articles, such as Wmazz's blog on pwctoday. Buy an rpm gauge.
Start by setting idle and low speed by doing the idle drop test listed in his article, set the high speed screw 2 full turns out? If it hesistates your popoff may be to high, if its slow to accelerate maybe the pop off or pilot is too high? It's possible the carbs may not even be tunable.
Reading Wmazz's blog will help you the most.
It's all trial and error.

 

[eastcoastjumper]

Tuning is the last step after everything else is assembled correctly, in perfect working order, and all other bugs worked out.

Its hard to know what condition any of these parts are in, or if its leaking air, or maybe damaged in some way/has electrical problems. There are too many variables to work with when every piece relies on another to make it run.

Is you ocean pro head high compression? Maybe its a (race gas high octane) ocean pro swirl dome head. THis thing could be a time bomb and blow up on you going off someone elses online advice.

Take a few detailed pictures so people can see what you're working with. Maybe someone can identify your ski.


Its a long shot trying to get a correct tuning specs online. Even harder when you don't know how to make or feel the correct changes.

 

[550surf]

thanks so much guys,

i totally understand that no can really give me deffinate awnsers, although im very thankful for the carb settings dartman ( lol you were the "forgoten ledgend ")
kswitak, thanks for the direction ill look into it.
eastcoasterjumper, i just totally rebuilt the top end new pistons, bore and hone, crankcase is gone ( words from the machinist) its been my first mechanical experience-running now 6 months long but ive learn alot. but yeah dude, everything other is in top working condition. im sure its got a high comp head, PUMPS out the psi, ill take a reading when i can but its easily over 160 maybe even 180.......

While I have you all here,

id like to ask how I go about flushing my engine( i ride salt water so u must flush it out with fresh water)
I am running this cooling set up and i need to be able to flush both cylinder with one flusher kit

 

[550surf]

i think i have to install it on the front cylinder.
will doing so pump/suck water ACROSS BOTH cylinders?

 

[eastcoastjumper]

Make a splitter and jam it into your pissers and back feed the motor and pipe out the pump. I run my motor separate and my pipe separate so I can do one at a time with a hose handle

 

[Dartman]

with the diagram you posted
put the flush fitting 'T'd in between the rear head outlet and the bottom of the headpipe line

 

[550surf]

okay thanks guys

 

[550surf]

dartman, are you sure your methods provides adequate cooling to the engine? like i dont want water going to say the pipe more than the engine....also will this flush both cylinders?

 

[550surf]

could you have say, 2 T pieces, one on each hose , and it joins to a single "hose fitting". havng a tap below the connection piece.
would this work? spliting the water from the hose into the two "water intake hoses"

 

[Dartman]

dartman, are you sure your methods provides adequate cooling to the engine? like i dont want water going to say the pipe more than the engine....also will this flush both cylinders?

as long as you have good hose water pressure
you'll be fine
yes it will flush both cylinders
550/440 engines have a very open cylinder water jacket
their all connected as one

 

[550surf]

thanks dartman tho ive opt'd to install a T piece on each water hose ( bulkhead > exhaust mani hoses) and connect them with a Y piece to the garden hose.

cheers