OKO pilot circuit holes

[whitexr]

Ive been trying to tune my oko 26mm flatslide carby to my bike and after stripping it down i found the pilot circuit holes dont look like they had been drilled properly


this just does not seem right to me!
should i drill them or leave them?
has anyone else found this?

 

[my67xr]

they are small holes,
try poking a strand of wire from a wire brush through it.


what bike, engine and jet sizes do you have ?

 

[whitexr]

yeah i tried that. but it just didnt seam right to me lol
ive got a motovert with a jialing 124 hc piston tb cam port matched head and tb manifold.
i tried 36 pilot and 94 main but it splutters until its really revving so im going to order a 34 pilot and 92 and 88 main from dhz today.
i understand that the carb maybe slightly to big but i had it sitting there as i put a genuine 606 mikuni vm26 on my 150 in my postie.

 

[my67xr]

so it hesitates a bit when you blip rev it?

if so i would be trying a #38 Pilot jet in it, the main sounds pretty close to what it needs though.
you need to sort out the Pilot first,
then you can adjust the needle clip to fine tune the main jet.

once you can get it to blip rev freely/crisp,
you will need to do a couple of WOT runs in 3rd or top, on a slight incline, and switch it off, pull the spark plug out where you stop, and check the colour on the porcelain near the electrode inside the plug.
it should be a coffee brown colour.

 

[whitexr]

i did try a 38 and evan a 40 but ill give it another go since then i did adjust the valve clearances again

 

[whitexr]

it hesitates a lot when i blip the throttle lol

 

[my67xr]

the main may be a touch too small ?
did it come with a #100 Main jet when it was new ?

 

[whitexr]

yeah it did ive also got a 96 and 98
nothing really made much differance

 

[my67xr]

with the main jets, you will only really notice it at higher rpms

 

[GooseMan]

sounds like it is rich in the pilot jet, I would try a smaller pilot, leave the main as 94 and see what that does. You agree craig?

 

[NSALT]

I had the same issue and thought the same thing about the pilot circuit holes I have mine on a z160 though. I did drill the holes out with a 0.5mm jet drill but made no difference it was like i had a leak somewhere making it lean in the bottom off idle I ended pulling the head off and found I've got a slightly bent intake valve.

 

[pitsterproAUS]

the pilot curcuit of the 26 NEVER have a any dramas the 28 does

keep the 100 main
the jailing has a old school heavy flywheel u never going to get it to blip nice and snappy,
the 28s bog down cause they are to lean , once u fix the with fat pilot it dont idle ,,

 

[zwebx]

yeah +1 to that your carby has to be atleast a couple mm smaller than your intake valve or by cc to correctly atomise the fuel and give a proper burn therefor spluttering like spraying a spray bottle with the tip off compared to with it tight it does not swirl around the head and burn right..
eg pour a little fuel on the ground then light it it will go up slowly.. pour it on somthing that absorbs it let it sit for a little and then when you light it it will go up really agressivly and fast because your lighting the vapour.. (also found that out while drinking and trying to start a bombfire not nice but now i know)