two skis two fuel problems

[feartheride]

Ski #1
After a couple of major setbacks with my Lamey cyl and only 2 hrs. riding time since last aug. it is rebuilt and trying to tune again
Lamey cylinder,b pipe, ada head 180 psi .039 squish,msd enhancer,ported,delta 2 reeds
46 buck shots 125 main,125 pilot, 2.0 n/s, 18 pop off
It seems to run fine accept when I land upside down or on it,s it sputters and within minutes fouls the front plug.Twice I rode for an hour and then when I landed upside down fouled the plug
I,m thinking pop off
I have 44 mikunis that I will probablly end up putting on mainly to get rid of the prok filters that have to be used on the buckshots but I would like to know that the buckshots work
Also it surges when trying to keep it at midrange.Is this in the tuning
Ski # 2
also been chasing this problem since last years Jersey Rager
701 fresh rebuild ,pro tec mach 1, stock carbs 2.0 n/s 35 pop off 135 h 75 low,r&d head 160 psi
It seemed that it was cutting out sporadically and I thought it was electrical changed cdi,coil,stator. No luck!! must be fuel.Now i have notice it seems more noticable when you are hard on the throttle and then let off and get back on.It bogs so bad that it stalls.It fires back up and takes a moment to clear out.As long as you stay on the gas it is fine.
I had a needle sticking so I bent the lever till it was flush and did not stick ,thought that was it ,wrong still there!!!
I tried another set of carbs and it is the same but not as bad

HELP!!!!!!!!!!!!!!!!!!!!!!!!!!

 

[Matt_E]

Ski#1: Could be low popoff, true. However, if you don't see fuel dribbling into the carb at idle, you're probably okay there. Does it have a primer?
Other than that, I have no clue on that setup.

Ski#1: Look at the Mikuni tuning manual. Your one-way check valves (plastic "fingernails" underneath the jet plate) needs to be doubled up, i.e., put two there instead of one.

 

[SUPERTUNE]

#1 Get rid of the Buckshots, way to fussy everyday. Just use std 46's...
#2 Try re-gapping the plugs to .022...

 

[waxhead]

ok here is what i would do with the landing flaming out ski
pull the carbs off
check the pivot arm for the n/s
make sure it doesnt have a big divot worn in it from the n/s
if it does then replace it
also make sure it hasnt opened up where it swings on the shaft
What happens when they wear is you get in consistant popoff readings and big bangs make them jump about and drop a load of fuel down your carb
also check the sides of the n/s
make sure that the 4 runners on the needle arent worn as they will tend to shake around and also dump fuel on landing
hope this helps

 

[waxhead]

ski 2
you say it bogs as in like goes way rich or lean ???
i always set my race skis up like this
a big run and then off the fuel
stab it back on if it doesnt carburate cleanly then i put a larger low speed jet in it assuming it was lean if it was rich of course i go the other way
in other words you may find your low speed is to big in this instance

Another thing to think of if its going lean is your pumps
as you back off you lose alot of pumping pressure in the cases and the fuel pumps cant supply the fuel for the sudden full load again
this is more of an issue with an off its head ski that sat the max of the pumps delievery capcity and i dont think that this is this boat

hope this helps as well

 

[feartheride]

Thanks for the input I let yoyu know how I make out
I did not think that the 701(#2 ski) was jetting because it ran for years with that jetting and then suddenly acted up at jersey rager but I will check it out.

 

[waxhead]

ahh you never said that
ok i will have a rethink

 

[Matt_E]

Your needle & seat valve may be starting to get worn then. Pull them and inspect for grooves in the needle.

 

[feartheride]

One other thing that is not relevant is that the 701 ran great until it was running wide open and would die .Last summer when I was at jersey and this problem started we pulled the carbs off at Paul's shop and I found I only had one main jet,must of left one out 3 months earlier when i had the carbs apart.

 

[feartheride]

Okay yesterday I took the buckshots off the lamey motor (ski#1) and put on new 44,s. I don,t know why it ran great with the buckshots but would die and instantly upon restarting foul a plug and have to limp it in on one cylinder. Happened 4 times in ar ow .It is not doing that with the 44,s
I have112.5h,120 lows, 2.5 n/s with 115. I used the 2.5 because thats what the came with and I did not want to try the used 2.0,s out of the buckshots yet.bottom end is sluggish mid is still very strong.
I have found with this motor that it comes on very stong at mid but I don,t like the way it surges ,it is hard to keeg it at a constant mid speed.Any one else have this problem,how can I smooth this out or can't I

 

[feartheride]

As for the 701 ,b pipe and stock porting with 38,s I am at a loss I borowed some other stock carbs and it does the same thing every time you back off the throttle and get back on it it does not want to go ,sometimes it dies completely.I don,t believe it is jeeting because I ran it for years like this.
NEED HELP WITH THIS ONE PLEASE

 

[Matt_E]

Check your fuel tank and filter for debris. How abou the plug wires?

 

[feartheride]

installed new filter,drained tank twice no sign of water, checked pick up, reconditioned stater and coil installed last week from jetski soloutions and a used proven stater