Monthly mikuni carby thread

[Oznewbie]

Hey guys,

I know it gets asked alot, but I have searched and have read alot of different answers.

My carb is being a p.o.s and I just don't seem to be getting anywhere with it!! Necer really ran right since I got it

I found the spacer to be smaller than the carb intake, so bored it out and sealed using silicone

I've tried needle in middle, 2 1/2 turns on mixture screw. Needle on middle and 2 up also.

I read alot of re-jet answers.

Can someone please tell me ... For standard setup for minuki 26mm intake (makes it a 22mm right?) on a 125 (ducar engine)
A. What size jets
B. How many turns on mixture
C. How many turns on idle
D. Middle position on needle?

Thanks guys, I'm really strugglin, not suprising since I've never setup/worked on carbs :S

 

[my67xr]

i would be trying out a #20 pilot jet,
fuel screw 2 turns out.
idle speed screw, as required to idle
middle position for the needle clip, until you have the pilot jetting sorted

 

[Oznewbie]

Ok, ive dropped the needle clip to the lowest setting and it's not spluttering as much

The mixture screw works what way ?
In ...
Out ... ??

Think I should try and adjust the mix screw ? Or throw a pilot jet in and start from there?

 

[Oznewbie]

Just went and stripped Carby, it's got a 95main, 15 pilot.

Getting better as I drop the needle.

Running lean ? All tie in/sound right?

Unfortunaly Plug chops haven't been successful :S lol
I can't cut the kill switch from flat out and always cutting at a rolling stop - I would say reading black, dry, slightly sooty ... Hence thinking they unsuccessful

 

[my67xr]

try a 20 pilot jet for sure, it will make the carby totally useable.
lowering the needle will help a touch, but it is covering up the main problem, the pilot is too small.
the mixture screw richens it as you undo it , leans it as it is done up.

post up any findings

cheers, craig

 

[Oznewbie]

Ok. Thanks

What you think about the plug chops? Unsuccessful readings?

Does it all sound right ?

Should I go 100main. 20 pilot. 2screws out on the mixture. Middle on needle ?

Thanks man, really appreciate it. Just about starting to get my head round it.

 

[Oznewbie]

Dhz are doing kits (2 of each) for $18 delivered nice

Now, which kit :S
Group Slow Jet Main Jet
1. 15 ,17.5 + 92.5, 95
2. 15, 17.5 + 95 ,97.5
3. 17.5, 20 + 92.5 ,95
4. 17.5, 20 + 95 ,97.5
5. 17.5, 20 + 97.5 ,100
6. 20, 22.5 + 100 ,102.5
7. 20, 22.5 + 102.5 ,105
8. 22.5, 25 + 105 ,110
9. 22.5, 25 + 110 ,115

 

[my67xr]

i'm running the #20 pilot and a #95 main in my Mikuni china 26mm,
this is on my Lifan 125, it runs very well for me.

i guess at that price i'd go for option 5- 17.5, 20, 97.5, 100

yeah that is a good price, my #20 pilot was $6 iirc.


fit the #20 pilot first and see how it goes, make the required adjustments after a ride
then if it runs best with the needle clip on the bottom position, go for the next bigger main jet the 97.5

 

[Oznewbie]

Now I'm confused again ..... Thanks to this ..... http://www.ozebook.com/compendium/t500_files/mikuni.pdf

The long style main came out of mine ?

Is that what all mikuni 22s have ? And dhz are just using a generic picture (of the short ones) that's confusing me ?! Lol

 

[my67xr]

make sure you are using a brand new spark plug when you do your chop.
and use a CR7EIX, here is the cheapest i've found, OS - http://www.ebay.com.au/itm/NGK-QUAL...L_Wholesale_GL&var&hash=item27cb5bb8a0&_uhb=1

and it is best doing it at WOT, this way the plug is running in the self clean temperature range.
slower speeds it'll probably show up slightly rich

 

[my67xr]

is the main jet round, with a flat screwdriver slot in the head of the jet?
then theres a hex head below it?
if so hold the hex head with a spanner and undo the main jet out of the jet tube

 

[my67xr]

main jet top left, pilot bottom right

edit- there were 2 sorts of pilot jets used in these china copy carbys, make sure you get the right type.

 

[Oznewbie]

Using brand new plug, denso tho. Smallwheeldeals say that's all they use and it's all they had.

Must be where I'm showing slightly rich.

Il get the 20 pilot in there and check it out from there.

I'm getting sick of taking this carb off tho lol

Any cheap thumb screws for these mixture screws ? Or tips/tricks for adjusting when on

 

[Oznewbie]

My main looks like this one

 

[Oznewbie]

Just seen your explaination of how to split !!

Thanks man! U kno your carbies

Il update in couple days when I get my jets

Thanks again

 

[my67xr]

My main looks like this one

do you realise thats your pilot jet?
looks like there are 2 different types of pilot jets, the vm22 type, and the vm28 type (the type you posted above)


you might want to post some pictures of your carby to make sure

yeah, let us know how you go

 

[Oznewbie]

Na with the tube on the main, it looks sorta like that.

Know I've split it from the tube, it looks just like the ones you posted!

Thanks again

 

[my67xr]

aah, ok then

 

[Oznewbie]

I'm just going to get them now,

Should I get a 100. Or 97.5 ?

If I get a 97.5 and put clip in the middle ... It would b similar to my 95 with clip at bottom ?

So should I try 100 main ?

Rhanks

 

[my67xr]

sorry mate, been working outside
id go for the 97.5 maybe?
possibly you'll need a smaller main once the pilot is sorted?