24mm carb tuning :(

[Bekass]

Hi!!

I own a sym orbit 50 wich is almost the same as the kymco 50cc. some time ago i had installed the 82cc airsal kit with stock head and 24mm runtong carb with 118 main jet.
now i needed a bigger kit so i went for a 85cc with big bore head and valves, camshaft, naraku ignition coil, twin air pit bike filter, and my runtong 24mm carb.
now whats strange is that with the 118 main jet its way to lean and im runing currently on a 150 main jet  .
im really confused
is there anything wrong with the carb? and i can get past 75km\h is suddenly bogs dow. with stock carb and 100 main jet, i can pass 85km\h and a straight road 
the 24mm delivers a strong punch but bogs at high speed

can anyone help me 

cheers!

[LoveMyKymco]

Sounds like its still lean, are you running an open element air filter, IE cone filter uni etc or something else? I would try to run it with part of the filter covered up and see how it does, if it runs better covered up partially its lean still, if it gets worse its rich.

[blue]

I would say stop befor you blow it up . just get a bigger scoot.

[Bekass]

yes im runing a twin air cone filter. but seems strange runing lean on a 150 main jet???
can the intake manifold have something to do with it? it shows some cracks on the rubber

cheers

[Bekass]

Whats in your opinion the best carb for the 85cc bbk ? the 19mm? or the 20mm?
there is something very wrong with my 24mm

[LoveMyKymco]

19 is good, 24 is my choice. Its possible theres an airleak somewhere. You need to do a leak down tester and make sure.

[Bekass]

the intake  boot is a bit cracked on the rubber outside, but since its all aluminum inside i thought it was ok... how do i run that test to see if it has a air leak?

what size of main jet are you runing on the 24mm carb?

thanks for the help...

[streido]

If by Intake boot you mean inlet manifold, hose from carb to case, then just replace it. I picked one up last year for about £10 brand new. Dont overtighten the clamps on the end when refitting it, that tends to be how they split.

[Bekass]

yes the intake manifold. ive taken my 24 carb apart, sprayed it with carb cleaner and used compressed air to clean it, tommorow ill see how it goes. im gonna buy a new intake, mine looks ugly, the rubber is full of cracks that reach the aluminium inside...

if i raise the needle i can go down on the jets can i??? my needle c-clip is working on the middle.

im thinking of ordering a ngk iridium plug, is it worth the money??

all the best!

[Bekass]

got new high temperature o-rings and sealed completely the manifold. i had some small poppin when desacelarating, now its gone, but above 60kp\h is still a bit weak and struggles to reach 75kp\h on a flat road. im still on the 150 main jet.

im thinking of raising the needle a bit, is it worth it?

can anyone help me out?

cheers

[The Rookie]

You need to figure if it's rich or lean first, as above, block off some of the air intake (which will richen it up).

Larger carbs need a bigger jet as they develop a smaller vacuum.

[Bekass]

i raised the needle today, it ran a lot better. im runing a quite large jet for a 85cc, the problem was the damn needle lol
no more boggin at high speed. it runing very smooth now. ill do some plug chops tommorow to check if its ok

its givin the 50cc 2 stroke some trouble uphill  hehehehe