oko 26mm pilot circuit issues

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Perthrider

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After installing a oko 26mm flatslide from dhz, my bike (dhz 140 outlaw ( the one with the zongshen)) is sluggish and usually bogs down and dies when accelerating to WOT off idle (top end is fantastic though, way to go oko :action-smiley-033: ). I have fiddled with the air mixture screw to the ends of the earth and it seems to be running best when its screwed ALL the way in (or sometimes quarter of a turn out) however its still unresponsive and stalls which is driving me insane, especially when in a berm and nearly been collected by 250. It has a 98 (soon to be 96) main and 36 pilot with needle clip one up from centre (and im at sea level if that anything). I'm guessing ill be needing a larger pilot but everyone seems to be running 36's with no problems.. well according to thumps 'post you carby settings' anyway. Has anyone else had this problem? is it even something that can be fixed and just a common quirk with the oko's?

Hope the post wasnt too long and i didnt forget something, any help greatly appreciated!
cheers.
 
Most stock bikes will bog when you wrap the throttle from idle to wide open. You have to roll the throttle as the engine speed builds up.
What slot do you have the clip in on the needle??
 
I had a 36 in my pilot and a 98 main and it ran OK. Had an irratic idle and bogged if I rolled the throttle on too quick. Changed to a 38 pilot and a 102 main and its heaps better. I read in another thread when tuning it, get it to idle, wind the mixture screw in until u hear a change in revs or engine noise, then wind it out till you hear the same but count the turns. Now screw the mixture in half the amount of turns as you screwed out and adjust the idle screw to a sensible idle. Keep doing this until you have no more bogging issues. Doing this tunes the car by to the 'sweet spot'. This was coming from the member cactus.
 
Looks like i might as well just grab a 38 and see how that goes, and a 102 main on a 140?? thats huge! DHZ the clip i one up from the centre, its in the post :)
 
I had the same problem as your having at the moment, ive got the same bike and carb setup cant remember exactly what settings i have, i think 98 main 38 pilot and clip one down and found that mine runs good with the mix screw only a quarter turn out, mine was also bogging bad all i did was idle it then wot and turn in the screw till theres no bog and it runs hard with no hesitation. Just remember that what ever setting you find works best with no bogs is actually running a good spark plug reading, so plug chop before you decide to leave it, mines a tad rich but better that then lean. So i hope this helps you in someway, also what works for some wont work for others, so go with what works for you mate.
 
Looks like i might as well just grab a 38 and see how that goes, and a 102 main on a 140?? thats huge! DHZ the clip i one up from the centre, its in the post :)

Sorry mate missed that bit. Put the clip all the way up and see what it does.
102 is huuuuge for a 140.
I would be running 36/96 or there abouts.

Running an engine rich can be as harmful as running then lean.
 
thanks brendo thats the sort of answer im looking for! one clip down though? is that from the top or centre? cant wait for some free tinkering time now. where abouts do you live? altitude wise haha. no pedo.
 
sorry dhz didnt see you post, ill try moving the clip some more and see how i go thanks, and yeah 102.. sh#*.
 
My mixture screw seems to only be 1/2 turn out from seat as well.
E Clip on position 1 below middle.
If i turn the mixture out more it becomes duller in note and tends to hiccup through the carby a lil at idle.
Would i be right in thinking the E clip needs to be in the middle and then the richening up that will do will allow more adjustment on the mixture screw??
 
My 140 has had the head ported, a2 cam, HD valve springs, manifold match ported. Runs like a dream. Better with the 102 than the 98
 
Ive found after constant tinkering that the 36 pilot with the screw a quarter turn out seems to be best, well as good as i think im going to get it. The strange quirk ive had is that to elimate the bog and get the best throttle response possible, the pilot circuit must be extremely rich, which means eating sparkplugs like cereal (fouling). Either im completely missing something here or its just trying to get to me. At the moment im fiddling with the clip position, as theres a large flatspot at about mid throttle with the clip in the centre, running rich? Then maybe next year ill get to the main.
Curse this tuning quackf$&kery
 

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