125cc bogging down

[sam93]

I have put on a new carb, and its bogging down a fair bit and my old carbie didnt. trying to find the reason...jets?


Engine:
Ducar 54mm x 54mm 124cc

Carbie:
Old: 22mm Jk
New: Pz26mm Mikuni

Filter: Standard duel layer...

Mikuni Jets:
Main: 95
Pilot: Not sure...


Any advice would help a lot.

Thanks people


also i know people are going to just tell me to through the carbie in the bin and get an oko 26mm haha but i want to get this carb running right i got it for free...

 

[china boy788]

that 26mm carby is rly a 22mm, and are ur jets blocked??? are you running too rich or lean??

 

[sam93]

Yeah i knew it was a 22, and nope jets arent blocked, and im not sure, like i would think that i should be running it leaner but it wont run. I have tried every setting on it...the only 2 settings that will actually be able to ride on is bottom and second bottom settings...the very bottom boggs at start off like it wont pull a mono but the 2nd setting will but then it still boggs down...

 

[china boy788]

so it only run when the clip is on the low setting on the needle??

try turning ur fuel/air screw out to make it richer,

or ur pilot jets way to big or too small,, should be about 15 or 17.5,

clean ur carby and check it

 

[qwerty123]

its a bigger carb thats y u cant slam fullthrottle from idle

 

[sam93]

Yeah it will only run on the bottom to settings (the 4 above that wont even rev in nutral)

Where is this air/fuel screw?

I'll clean it out again but i did just last week and i have only ridden it for an hour but just to be sure.
and ill check my pilot...

What jets do most people run with a 125? a 105?

 

[sam93]

I never said that it is just bogging from idle its the whole rpm range, if im crusing any gear i cant just give it half throttle and go it boggs down and then decides to go after 10 seconds or so...

 

[bulldog93]

It sounds like it's running rich. It should sit in the middle grove. Take a look at this:
- http://www.miniriders.com.au/carby-tuning/24570-carby-settings-your-bike.html
- http://www.miniriders.com.au/carby-tuning/25351-different-carby-types-chokes-idle-screws.html

The air/fule screw is on the bottom of the carbi. Jetting??? I don't know about that stuff.

EDIT: Woops running lean. If its on the bottom grove it'll lift the needle higher to get more fule in it. SO if it's running rich you won't less fule in so it should bo on the top grove. Is that how it works?

Thump*
DvDRip

We need your help.

 

[sam93]

yeah thats what i thought running to rich so lean it out right?
nup it wont do it. the only setting it will run on is literally the bottom 2. my old carbie the jk 22mm ran on the middle setting. It didnt bogg down at all...i know the mikuni is bigger but it still shouldnt be bogging this much...its seriously slower than the sh!tty jk.

 

[qwerty123]

its not the jetting or needle setting!!

clean ur jets i bet u they are clogged because when i rode it it was fine and ran beter than your jk or have u tryed stuffing around with the fuel air screw??

 

[china boy788]

EDIT:[/B] Woops running lean. If its on the bottom grove it'll lift the needle higher to get more fule in it. SO if it's running rich you won't less fule in so it should bo on the top grove. Is that how it works?

Thump*
DvDRip

We need your help.

anit it the other way???
down is richer and up is lean for simple

on my ducar i rn 95-15 and the neelde in the middl, but had to play with the fuel/air screw a bit,

 

[sam93]

I just played with the air/fuel a bit, its running a little better now. I did about 5 adjustments it ran better when i screwed it anti-clockwise (im not sure if thats leaner or richer) but its still not feeling right...

 

[bulldog93]

I've confused myself . Found this:
Bike idles very high – too lean on pilot circuit, throttle piston the wrong way around, air leak at manifold.
Bike hiccups at idle – If the hiccup slightly slows the engine but doesn’t cut it out is a sign of rich pilot circuit (eight stroking). A louder hiccup that can stall the engine may be lean conditions spitting burning fuel back through the carb.
Black smoke out of exhaust – rich conditions at the throttle opening it occurs at.
Stuttering – If the bike stutters at full throttle but is alright at part throttle the problems lies in the main jet, if the bike is fine at full throttle but bogs down at part throttle the needle needs to be adjusted. By understanding which jet area of the carb is functioning at which throttle opening jetting problems are more easily fixed.

- http://www.miniriders.com.au/carby-tuning/20778-carburettor-tuning-guide.html

I'm so confused right now. Here are some threads:
- http://www.miniriders.com.au/ask-tech-masters/25238-fake-mikuni-air-fuel-screw.html
- http://www.miniriders.com.au/tech-talk/25817-carburetor-problems.html

 

[sam93]

I guess it is needle adjustment then, because i just went out for a ride, when i am cruising and give it a little bit of throttle it craps its self then i snap on full throttle and wait a few seconds and it pulls...im confused to.

But as far as the needle asjustment it will only run on the bottom 2 settings. all the other settings wont even rev in just nutral...and then the mixture screw at the bottom of the carby when i twist it in (clockwise) it does the same thing wont rev in nutral so i screw it out (anti-clockwise and it runs better but still boggs)

 

[DvDRip]

anitclockwise is richer, lowering the needle clip and raising the needle richens

to tune the mixture screw you should get a manifold adaptor so you can face the carby out to the left and tune it with the bike running.

definatly sound like pilot jet is too lean or bad mixture screw tune

 

[sam93]

I have one of those 360 degree manifold adapters...but i dont have the special screws for it (that fix the 360 degree...to the engine...where could i get them?

 

[DvDRip]

you need countersuck screws, from a bolt shop. I also had to grind the counter sunk slot on my adaptor so the screws wouldn't stick out the top

 

[thump*140]

Samray if you pull the pilot jet out of the old carby (should be the same style and thread) and put that in the new one, turn your air/fuel mix screw ALL THE WAY IN, then turn it OUT 1.5 turns...
If you have a 95 main jet, that *should* be ok...
By the sounds of it, too rich on the pilot, and possibly a bit big on the main... a 125 should be running between an 87 and a 92 main using a fakuni carby...
Try that, and see how you go...

 

[sam93]

Thanks for the advice thump, gives me something to try tomorrow ill let you know how it goes...

 

[Tai Chi Chameleon]

Very great advices from Thumper#140................................................................................................

It would be interesting to see how de fixes works..................................................................................