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yeah, are the holes all open in the emulsion tubes ?

have you checked the float levels by lifting the drain hose up near the top of the carby and opening the drain screw?
a few of the Oko's need to have the bottom of the float sitting 21mm from the base of the carby


you might need to pull one carby apart and check that the emulsion tube feed is open too

DSC01820.jpg


this page shows how to refit the jet block centrally
Instal
 
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will check the feed holes with some carb cleaner tomorrow, what am supposed to do with the fuel drain line? not to sure what you mean there tbh... reading the oko tuning guide now, thanks again for the link.
 
i just went out to take some pics, how to check float level with the drain screw
but Oko's don't have a fuel bowl drain screw/tube like the mikuni copys :11doh: , they have a big drain bolt so that idea won't work
 
haha all good mate, i will measure it from the base of the carb, that tuning guide is a really good one that you linked me up with, going to have another crack at sorting it out today
 
The PWK is a brand new carb. Pretty sure it's never been used.

I would be surprised if something is blocked. I think your jetting is just off the mark or you have another issue. If both carbs are giving the same symptoms then there has to be something else you would think?

You have checked your valve clearances and timing etc yeah?
 
valve clearances where done when i got the engine, i did take the head off, but kept the timing chain etc in the same position for when it went back on, so timing should be fine yeah? i checked wiring and earth to frame etc all looks fine. pwk had been used at some stage there was a little evaporated fuel in around the jets. Tried to play around with it again after reading that oko tuning guide properly and i THINK that the pilot jet is to rich, but there is only one smaller size available. In saying all of this, i did get the 24mm oko very close before i snapped the idle screw, needle on top clip and a 96 main with 36 pilot but the idle screws are not interchangeable between the two so i cant really test the oko atm. Will just keep plodding away get it in the end lol
 
The pilot jet shouldn't be the problem if it's bogging down after half throttle. In saying that I have a 38 pilot for both my 160's so 36 for a 125 does sounds a bit large. It would be revving pretty high when started if that was the case unless it did and you just toned it down with the idle screw? What clip is the needle on?

I would definitely check the timing again. I had a similar problem with my yx160 and found it needed to be slightly in front of the timing mark rather than behind as it didn't line up spot on (slightly advanced not retarded). That 1 tooth made all the difference and it ran like a dream afterwards. Thinking about it now it was exactly like the problem you are describing. Might be worth a shot?

It's really the process of elimination. Just seems weird you have tried 2 carbs with the same result you know? Even jetting that's close shouldn't cause those type of issues unless your main jet is way off and I think by the ones you are trying you have to be damn close.
 
will check the timing again now, i just had another play, and took the airfilter off to see what was happening, im getting misted fuel spat out of the carb as it gets onto the needle, as soon you give it anything above 1/4 throttle.
 
timing seems to be spot on, marks all line up... as i said before i did get the 24mm oko quite close before, needed the choke to cold start with the 36 pilot and with the clip on the very top it revved a lot cleaner than when i first put it on. Im getting the symptoms from the 21mm that i got at the start with the 24mm oko, i just cant get the 21mm even close, same jets and clip position as 24mm and its far worse. Waiting on a fresh can of carby cleaner when the missus gets home to give it a really good flush.
 
after further reaserch (lol) i have discovered a few interesting things. The needle out of the 21mm is much thinner than the oko needle, which is marked jjh (the 21mm needle is simply marked pw21). The cutaway on the slides are also different, the 21mm slide has a rich cutaway (smaller) and the oko a leaner cutaway (significantly larger) which i think has combined to make the 21mm far harder to jet and tune than the oko. I have scavenged the idle screw from the 26mm oko, put the 24mm together with a smaller main jet than last time (96 down to a 94) and am about to see how i go.
 
yeah the Pilot should be pretty close.
if it was too small it would have rev hang, the idle would take a while to come back down

the OKO 24mm is a powerjet carby isn't it?
if it is, try taking the hose off where it goes onto the jet at the top of the air filter side, and block it with a ball bearing or screw, and try it again.

edit: do you have a boot sealing the cable to the carby top ?
 
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no i dont actually, neither throttle cable i bought came with one. I do have some electrical tape around it though. I managed to get running quite well with the 88 mains and 36 pilot, a/f screw only 3/4 of a turn out from fully closed. Wouldnt run right with the 35, rev hung quite a lot and needed the a/f screw to be done up tight to get it to run at all. Thinking i will block the power jet off like you suggested craig, as it still runs best with clip in the top position. Im also wondering if the intake manifold could be causing me some tuning problems, as it is the daytona manifold and is quite large in its i/d..
 
with the mixture screw at 3/4 turn out, it is still too lean, that needs a #38
then the mixture screw can be turned out another full turn, to 1 3/4 turns out
it might help the transition from running off the pilot to the main jetting


have you tried slowly opening the throttle past half way ?

the big id manifold, is it any bigger than the port on the head ?
 
will try a 38 tomorrow see if its any better, i think the manifold is bigger than the inlet port actually. Might have to forgo the bling for a more practical one (thanks motor man for including one that will be perfect with the carby) with the oko set at the above settings i can get to wot which i couldnt before, and it is quite ride-able how it sits.
Cant believe your idle screw snapped to blender, that sucks!!!!!!
 
So sorted the jetting out after discovering the exhaust gasket ad disappeared at some stsge in the build. Its now running 36 pilot and 85 mains with air screw 1 and 3/4 turn out. Boys are loving it
3ce63d1268c43ab3f0f169db5c557e99.jpg
087f891b25afee0c32db79863da1626e.jpg

Dont mind the scrap either, we dont have rubbish collection
 
having a ride with jayden, damn slippery actually

[video=vimeo;109308411]http://vimeo.com/109308411[/video]
 
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Oh its a student free day, and its raining?! Time to the tear the back yard up!!! [video=vimeo;109896683]http://vimeo.com/109896683[/video]
 
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looks like a lot of fun!

next project you'll be building a drift car for them with those riding skills !!
 
Jayden has been loving his bike, we went a trail ride yesterday afternoon which was so cool. 110 running strong, finished up on 35 pilot 80 mains and tge power jet blocked off. May be throwing a remote res dnm shock under it to help with his landings. I should of bought him a kx 60 tbh, but its all a learning curve.
 
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