hard starting?

ok back to pop off, the most pressure i could get out of my carb is 21 psi, i have the gold spring and my needle valve doesnt have any writing on it.... but my book says for the 2.3 mm needle size and gold spring its supposed to be 22. and yeah i'm squirting some wd on it before each try...
 

Ericfox

Do it twice?That's DooDoo
is it a clean pop? you should soak the needle/seat with some wd40 and work it a few times before testing the popoff each time... and it should be a pretty clean POP
 

Ericfox

Do it twice?That's DooDoo
well if i read that right then you had less than 5 lbs popoff prior to switching to the gold 115gram spring.... that would be way to low which would allow a crap load of fuel into your carbs at idle which would then make it so you would have to hold it wide open to start it.... if you made 21 lb popoff then that should be close enough... you can always downsize your needle seat to a 2.0 if you want it higher.... hope that fixes it for you!
 
OK so FINALLY started up my ski. yay all good it starts up just fine, now it just hesitates A LOT mid throttle to high trottle. maybe my pop off is too high now? i dunno but i'm just glad it is rideable for rock and ride this weekend!

my pilot jet is 115 now and pop off is 21 lbs and still reading lean,the bottom screw is 2.75 turns out..
 

Ericfox

Do it twice?That's DooDoo
forgot to add, i pulled my return line off and no fuel comes out of it. think maybe i have a fuel pump problem or does it just not pump enough at low rpm to return?.

your bottom screw only contributes a little bit to the mix... if you open the carb butterfly about 1/4 and hold it there (about 20-30 secs) while riding (all this stuff has to be done in the water by the way...) and then punch it and it hickups... then your low speed jet is too small.... if you hold with butterfly open 1/2 way for same amount of time and then punch it and it hickups then your high jet is too small... you can make the low contribute more but then you will prob be rich for the rest of the range if you crank out that screw like you have it... maybe you're confusing lean and rich feeling? I doubt 21 psi is too high for popoff... what are your plans for this weekend? You dont want to ride much and hard like you will up on erie with a ski that isnt tuned right... you will be pissed if you have to do a top end because of it...
 

Ericfox

Do it twice?That's DooDoo
Im also confused... just read back through your posts here... you started with a 120 pilot and main jet... then you say you have a 125 pilot... now you say 115???? so what are you running for pilot and main jets REALLY??? I would prob say you should be more like 120-125 and 140-150 or something.... do you have a bunch of jet sizes we could mess around with at the ride??? or better yet do it before the ride!!! You have to test different jet sizes... you cant just go with a recommendation though.... so get to it!
 
ok for jetts. i have a 115 in there now, pop off is at 21 and the bottom screw is 2.75 turns out. main jett is a 125.

there WAS a 125 in the low end jet but i swapped it for the 115.
and now the plugs read lean. not really going by feeling
 

oldskoo

local jackass
Location
Cleveland Ohio
woooo 2 3/4 turns out>? That low speed adjustment is very sensitive! is it gurgling or turding out then hitting hard>? Yea get that figured out man it is a solid 5 min ride to the beach at edgewater w/ no where to stop in between, just big rock walls, bad place to break down
 
i think your low jet is to small but I am no expert. I have a bunch of jets I can bring to R&R if you need them. I think your going to loose your top end that lean. I had a ski with great top end tuned and i thought I had the mid good but i settled down to cruise, siezed piston.

there are differances in the Mikuni parts to a/m, I have found the a/m parts to be unreliable.

I was under the impression that, (in this case) a larger low jet would reduce the # turns out the low screw would require
 

oldskoo

local jackass
Location
Cleveland Ohio
i beleave you are correct because the screw controls the bypass circut, i think they say no more then 14- 1/4 turns out witch would be 3.5 turns out
 
def need to up jet to 120 low, i think your pop off might be low, I go by Group K's web sight saying no less than 24 pop of is needed for good linear carburation. But he doesn't seem to get into extream mods with a/m pipes and all that.

I have found to low pop off will cause over fueling @ idle due to drips down the bomb sight at idle, low pop off and engine vibration causing the neddle to vibrate, alowing unmetered fuel through. this will offset your set-up & cause further irritation due to bogs and hesitations that should not be there.

you can run the ski strapped to the trailer & verify the carb is not driping out the bomb sight with the air cleaner off looking down the carb. If it is driping you will never get it tuned right.
 
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