oko 26 carby on lifan 150

[darren89]

gday
Í'll start with my engine, engine is a lifan 150, ork, hbomb exhaust, custom made high compression head (alloy added to face), 28, 24 valves, upgraded seals and springs, and a matched cam for the head, porting and polishing job on head when was made and thats all i can think of atm.

Ok now i have just put an oko 26 flatty on it, and i can get it to run nicely low to mid and idle nicely, however as soon as i get mid to high it dies, i have tried a 96, 98, 100 main and was small differnces between them either die straight up or splutter and die but they would all die no matter how much tuning was done by me or my mate, carby has been cleaned(valves have been done), any help would be greatly appreciatted because im lost because i would of though with a 96, 98 and 100 mains i would of been able to elminate it

cheers Darren

 

[DHZ_XR8cing]

A 96 main is running ok on my 125 so id say a 100 0r 102 would be the best for you to try.

 

[aus_yzman]

Check out this thread
http://www.miniriders.com.au/carby-tuning/23986-those-about-rock-buying-oko-flatslides.html

 

[pbk]

hmm strange....

how many turns out is your mixture screw?

i would be sticking with a main jet of 96, 97 or 98

have you tried different e- clip postions?

 

[DHZ_XR8cing]

I have spent alot of time the last few weeks trying to tune my OKO and id call myself a battler more than an expert but i have managed to get it running pretty close to spot on.
Going by the problems I was having it sounds to me like your bike is leaning out up high so thats why i thought the 100 or 102 might be a good option especially with the mods you have done to your engine.
One thing I do know.When you get it sorted the top end will be enjoyable.

 

[sean01]

one thing to try is put an over the top main jet in it and see how it acts..
it will effect the lower range a bit but at least youll be able to see if it is a too fat or too lean condition..

throw anything above 102 and lower than 110...
if the problem is still the same then it isnt main jet related..

also might pay to check the choke mech out and do a plug chop in the problem area of the throttle range..

 

[thump*140]

hmm, this is a weird one... have rejetted quite a few lifan 150's recently running OKO 26's, they've all been perfect with a 36 pilot, and a 96 mainjet.... seems odd your's is coughing up top....
Have you done the valve clearances, or checked them lately?
I had similar problems last weekend, with jetting specs i knew to be spot on.... fixed the valve clearances, top end issues sorted...

 

[pbk]

I had similar problems last weekend, with jetting specs i knew to be spot on.... fixed the valve clearances, top end issues sorted...

i think you forgot to add that you orignally set your valves at 3.0mm lol

 

[darren89]

cheers for your help, yeh its got me stumped ay, because i have checked the valve clearances twice (didnt set to 3mm tho ), i set my valves to the usual .003 and .004, then i went to akunars clearances that he said to set with the head and he said .002 - .003 for both but after both different clearance setups it didn't make a difference, ive even thrown a new exhaust gasket in, checked for leaks, im really confused lol, would the high compression head (alloy melted onto head face etc and no base gasket), be a result for it may needing a stupidly big mainjet? (the head was a one off head built by akunar as an experiment for me, so i cant really ask anyone else with this head setup)

 

[darren89]

and cheers sean, i dont have a main that big, so i may keep playing around with valve clearances and tuning this weekend and if that fails, i will order some bigger jets

 

[darren89]

problem solved, yx 150 coming 7am tomorrow morning hahaha. i have had to many problems with this lifan 150 from the first day and its getting to slow now and cheaper to choose a new project engine and build it up bigger and better (so ill just chuck lifan in the 8 or 10 incha quad with standard carb for shits and giggles), so i thought i would give a yx build up a go, and in few months eitha go a yx160 or 160z

yx150, yx 150, crf50, engine, motor, pitbike, 125, 140 - eBay, Bike Parts, Motorcycle Parts, Accessories, Cars, Bikes, Boats. (end time 17-Jul-10 19:22:14 AEST)
new engine and exhaust , dunno weatha i should of bought it now haha i was just in the mood for something different at the time and a shitted off mood at my lifan haha, what you reckon? (i will be getting rid of irk and installing my lifan ork onto it, what work will need doing to fit it?) probs paid to much 430 but at the time i didnt get care lol was in the mood for a change for riding tomorrow

and are these kits any good Classic Honda 50's Australia - TB 170cc Bore Kit - GPX-YX150 [TBW9033] or better off going through akunar?
just till i decide what engine i want to build up
any help greatly appreciatted

cheers Darren

 

[DHZ_XR8cing]

Double check or even tripple check that you have no air leaks on your intake. The o ring may not be seating properly

 

[sean01]

yeah for the carb problem, i guess you could strip the carb to bits and make sure the emulsion tube isnt blocked(the brass bit the main jet screws into)

as for big bore kits, personally id go an akunar kit but case boring is needed.. so it sorta makes the pricing similar..

wat you could also buy which is pretty cheap considering the permanence gain is a yx 160 crank

 

[darren89]

yeh turns out the carb is sweet cuz tried it on another engine and i was able to clean the emulsion tube from the bottom when i changed jets over (cant tear it down because one of the screws on the bowl ate itself so ill get that saughted this week). it was the head on the lifan that stuffed up.

anyways with the yx, i havent worked on yx's at all yet, ive always worked on lifans, so im not sure wetha im confident enough to do a crank change in the yx yet (if it was a lifan i would).

but i bought this engine to learn about yx's so i guess i may give it a go, but im new to the yx world so still researching and learning all the mods and gains and performance etc

cheers again,
Darren

 

[wogtaz ryder]

Nice that engine should go alright , was looking at it for $350 but went abit high.

That header that he had made is nice lookin , i was interested in just that lol

 

[sean01]

all the bottom end is the same pretty much except there is no timing chain tensioner crap in the cases.
and the klx timing setup is a walk in the park

 

[darren89]

lol was that you with the 350 bid wogtaz? i waited till 2 mins before it ended and just went yeh i want it so went straight to 430 2 mins before it ended. and rocked up at 7am this morning, the pipe is nice ay , hes done alot of work to the head and the piping for the fmf pipe to run perfect in the head.

cheers sean, yeh ill see how i go with funds and see how nuts i wanna go, after i read a bit more threads etc. Would a 160 crank and 64mm piston and bore go alright? or should i go all out and get custom kit from akunar and modify cases etc? and custom head or v2 head.

lol should probably change title now