yx 196cc, OKO 28mm..which needle????

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ill see what i can do if i can sort this carb out..
oh and its not my bike...its one i ported the head on and the guy that owns it only used to use a shty china carby on the last engine....
am
and even tho the carb is up to sht the guy cant get over the power difference....
 
187cc with a bigger cam and most likely higher compression i was using (mikuni) think i settled on a 32.5-37.5 depening on weather for the pilot, and around the 125-130 for the main.....

If you are running 50-60 on the pilot, thats not right :/ neither is the 140 for the main....


The main problem with them is the taper on the needle... i had to stick mine in a drill and sand paper it to get a little more into the mid range...... OR just get a real carby :)


EDIT: as u dont give us much info on the motor we cant actually help u a great deal mate :) need specs.

If u are doubtfull on my tune have a look :- YouTube - Yx187 helmet cam

The miss on the bottom end was from my idle jet backing out, and this was running OVERLY rich at the time...
 
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daimojay said:
187cc with a bigger cam and most likely higher compression i was using (mikuni) think i settled on a 32.5-37.5 depening on weather for the pilot, and around the 125-130 for the main.....

If you are running 50-60 on the pilot, thats not right :/ neither is the 140 for the main....


The main problem with them is the taper on the needle... i had to stick mine in a drill and sand paper it to get a little more into the mid range...... OR just get a real carby :)


EDIT: as u dont give us much info on the motor we cant actually help u a great deal mate :) need specs.

If u are doubtfull on my tune have a look :- YouTube - Yx187 helmet cam

The miss on the bottom end was from my idle jet backing out, and this was running OVERLY rich at the time...
Click to expand...

lol, what specs are you expecting to see that i havent already mentioned...well the only thing not mentioned is the cam and thats because its standard(well assuming its standard, it hasnt been measured up)

and please dont take this the wrong way, but your bike doesnt excite me at all, it sounds over carbed and dead...but if you like it then thats all that matters
 
sean01 said:
also something for a look see...
TBolt USA, LLC » TB Parts » CHINESE ENGINES » TB JET KIT 26MM/28MM OKO (smaller)
Click to expand...

those are the jets they use in the roundslide oko's (that's why I asked if yours was round)
I have both a 26mm round/flat, the pilots for both are the same, but roundslide carb uses the round jets, flatslide uses the hex jets
if you look on TB they only sell oko roundslides, I think the previous owner of your carby must have got confused and bought the wrong jets.
 
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oh ok, i was unaware that they used different styles because they look like they run the same bowl so you think they would take the same jet..
 
yep they run the exact same bowl, but everything else about them is surprisingly different
 
To let you just how different they are, here's both side by side
img0397dq.jpg
 
DvDRip said:
To let you just how different they are, here's both side by side
img0397dq.jpg
Click to expand...

^^^^this is pretty much what i was getting at in regards to the "Mikuni" style main jets... ie: short round and flat...
The Keihin style jet (hex jet) is much longer...
Kinda what i was trying to imply in regards to the mikuni jet being entirely the wrong height, and making the needle clear the jet through the taper at entirely the wrong time/throttle position... so basically at half - 2/3rds throttle, the shorter main is thinking it's on WOT, and is dumping too much fuel through a tad too early in the throttle setting department...
 
Yes ... His carb will be suffering from severe fuel slosh with that short main jet ... Note this "new" anti slosh Mikuni TM float bowl !

PaxRacingStore

They also make 'em for Keihin FCR carbs ... I wonder if they'll make 'em for PWK's ... if they do they might fit OKO's ...

Team Show and Go Australia
 
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As for info on needle tuning ... The top of the needle taper affects the bottom end performance since it is sitting in the needle jet at low throttle openings ... and the bottom of the needle affects higher up performance ...

Jet Needle Changes
 
Hey mate,

Is there a review up for this motor? Really keen to see it in action and get some feedback for someone that owns one. Been wanting a new motor for a while but been holding out for these bad boys to see what they are like compared to the 155Z. Any info/advice would be appreciated. Cheers.
 
well just as a quick review,

even with the carb running funny down low the 155z hasnt got a chance.
we went riding yesterday(bush riding) our mate has a 155z and straight line and track style riding the 155z gets smoked, and not just a little bit..

what do you expect 196cc is pretty much going to smoke everything on a open track.
 
sean01 said:
well just as a quick review,

even with the carb running funny down low the 155z hasnt got a chance.
we went riding yesterday(bush riding) our mate has a 155z and straight line and track style riding the 155z gets smoked, and not just a little bit..

what do you expect 196cc is pretty much going to smoke everything on a open track.
Click to expand...

That's what I figured. Now to see how reliable they are. How long have you had yours and how many hours on it? Any other problems?
 
its not my bike but i have been with it every time it has been ridden.
it would have a max of 4 hrs on it.
starts first kick.

the last engine was a 176cc and it had about 15hrs on it and never missed a beat.
 
Sweet as. Sounds like it is a goer. Where did your mate buy it from and for how much?
 
you have to build it yourself obviously, all parts are purchased out of the country. i couldnt say for sure where he got them from.
 
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