For Those about to Rock... buying OKO Flatslides..

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DvDRip said:
see this is classic motorbike city bullshit, dodgyest bastards, don't believe a word they say

youd be better off with a 30mm Mikuni
which is really a 26mm mikuni! they just tell yu it's a 30mm becuz bigger sounds better....
this is th carby you already have and as I'm sure you know by now it's a peice of shit

the reason they tell you it's good is because they get them for around $10 each from china and resell to you for $100.....
they don't want you to buy an oko because they cost alot more from china and resell for the same price
so they don't make as much profit and n00bs end up paying top dollar for a shit carby

well thats unusual, most people are usually pulling those carbies off as they are shit

another line of pure bullshit... how can people be puling these off because they're shit when the only bike that comes with one stock is the revMX... and the revMX has only been available for a few weeks now
the truth is the other way around.. people are pulling off the molkts and mikuni's because they're shit.... and I don't think I need to say what carby they're replacing it with


and yes your bike with oko will KILL his bike with molkt
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what dvd said is 100% correct oko carbs are pretty much the minimum to use for a carb

all i can say is just go to a couple of races and check out the bikes and talk to some people

they are either running 26mm oko flatslides

or

kehin 28mm flatslides for those who are running BBK and a performance head etc

i still havent seen anyone running a mikuni flatslide but would be keen to try one
 
DvDRip said:
check out this thread I made yesterday
http://www.miniriders.com.au/tech-talk/28069-where-buy-keihin-jets.html

what engine is it for? and I'm guessing 26mm oko?
It's very unusual to need anything lower than 96 for an oko
Click to expand...


lol... always the way, searched for similar keywords, no hits as obvious as your thread title, cheers for the link!

Here is my original post on about pg 13 of this thread... i have the 96 already, but i live in the city and cant really test the bike without shitting my neighbours off, so i take it out to a mates place with some land, and i wanted to get the next size down as well just in case...

EDIT: I have put the 96 main in, and it seems to have made the bike easier to start as described below...

Bike and setup...

Lifan 125cc
OKO 26mm flat slide
Main: 100
Pilot: 36
Needle: E-clip on middle setting
Mixture screw: 1 1/2 turns out from seated

I have fitted up the OKO no drama's, had alot of difficulty starting the engine, pulled out the plug to check for spark, yep, plenty of spark, however i did note the plug was really wet!

Got the bike running, warmed it up, took it for a blast and did a plug chop, perfect tan colour and the bike feels stronger then ever in the top end.

So my problems, not sure if they're linked, or being caused by seperate issues, hoping someone can tell me;

1. When cold, bike is near impossible to start, engine getting waaayyy too much fuel. Once its warm, starts first kick easy as pie. (when i'm am trying to start on a cold engine i am not using any choke... figured it was a waste of time, already too much fuel...)

2. On a warm engine, from idle if i just crack open the throttle the revs pick up a tiny, tiny bit then just bogs, i back the throttle off abit, revs pick up, once they do, i can go WOT and its all good..., however if from idle i roll on the throttle smoothly/slowly/gently the revs pick up seamlessly...
Click to expand...
 
ok, just remember the mainjet only works from 3/4 throttle to wide open. so your problem isnt your mainjet its more than likely the needle setting..

never came across and OKO or keihin PWK that wont start with the choke once setup properly..
 
well akunar only have 90 / 96 / 98.... so you best looking somewhere else... but I really don't think you'll need any smaller... and 90 would be ridiculous small....

bogging down with a quick crack of the throttle off idle is common with oko's... but will be worse with the 125 because the carby is way too big... you just need to keep the revs above the level where it boggs or make sure you clutch it off idle
 
Just like to put a BIG thanks out there to all who helped me with my questions!

Finally recieved the correct manifold adapter today from DHZ and got the OKO flatslide working! You guys wernt wrong! These things rock!!!! I think its added about 35% more power!

I would say that people who say hard to keep the front down in 3rd gear may be slightly over the top, but BY FAR the best mod ive done so far! Although i now need to do a brake upgrade and blew my rear shock tonight also, not sure how (maybe all the extra power! HAHAH)

Thanks again Fellas!
 
Cheers again for the replies guys, my last dirt bike was an 07 YZ250, so clutch work isnt foreign and was sucessfully doing so last time i was riding the bike around with the K100 main in. Yes, i agree the carb is too big for the bike, but i didnt have acess to a smaller one and even with the 26mm carb, the bike is worlds better then before...

Sean: When you say adjust the needle clip, which way are you thinking, down the needle thus raising the needle up, or the other way?

Cheers, Lucas.
 
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I'm going to have to disagree with everyone here... you are running a lifan 125.. a 100 main is massively too big, and will be loading your carb up EVERYWHERE in the rev range...
I need to tattoo this somewhere i reckon...
OKO's have a peculiar symptom, of running weird EVERYWHERE in the throttle settings, if the main jet is too big... ie: if you are running a main jet that is too big, your pilot and needle settings will be off as well... It will feel like it's tuned perfectly down low and through the needle, but suck up top.. so you change the main jet, and all of a sudden that epic grunt you USED to have down low, has disappeared, so you start chasing different pilot and needle jetting....
Dylusion... Trust me... you need a 90 or 92 main jet for a 125 running a 26 mm oko, with no other mods... a 100 main is like using a bucket with a hole in it, for a carby... just draining fuel through the engine...
Try a 90 or 92 main jet, and see how you go...
Anyone else care to disagree, TRY IT!!!! :)
 
thats it thump, no matter how many facts you know, kids & there china bikes will always think they know better, hence why my advice is burn it.....
 
lol Thump... love the analogy, bucket with a hole in it...

Well, i will go about sourcing a 92 and let you all know! :)
 
Just bolted on a 26mm flatslide and kicked it in the guts.
1/4 turn throttle as well, the DHZ kit,

And I can't get the thing to pull a decent idle. Its going waaay fast, and I can't get it to come down - the idle screw is basically ineffectual, mix screw isn't really doing anything, so I'm thinking that the throttle cable is too 'tight' - will that mean that I need to slice a bit off the housing to reduce the tension??

I follow the pictures a few pages back, but it seems a bit of a ghetto fix for a reasonably new and flashy bit...!?

Thanks for any help.
 
What sort of 1/4 turn throttle is it? Is it Joker style with the wheel at the top? If this is the case, they should have send you a throttle cable that is about 30 or 40mm longer than the standard one. This could be why shes revving high.

Take off your air filter while the throttle cable is in position and look down the throat of it and see what the slide is doing, wether its closed or not (mind you it should be open about 12mm (roughly)). Easiest way to see would be to look at it now then disconnect the cable and then see how it looks.
 
ash what Beccs has suggested is right, the simplest way of seeing if a carby is "closing" properly, is to pull the air filter off and take a look up it's skirt... ;)
easier still, is to wind the throttle on with the engine off, let it go, and listen for a solid metal to metal "clunk!" from the carby, which will also indicate the slide bottoming out.... no clunk, no bottom... :)
 
hey thumb while your there, thought id ask you a question. I put my oko 26mm on few days ago and yeah wow what a difference, however i dont think ive 'lost' the bottom end, she still wants to mono etc when i take off. When people described the low end torque would be lost how much would be lost? ie should it feel slow until you hit x-rpm? If that is the case would i be correct in assuming my main jet is too big? I think they shipped it with a #100...which i imagine may be a touch too large as from memory you had quoted #95 to a few other people.

Bike details PP 140XR, twin pipes, 26mm oko carb, analogue racing cdi
 
beccsptyltd said:
hey thumb while your there, thought id ask you a question. I put my oko 26mm on few days ago and yeah wow what a difference, however i dont think ive 'lost' the bottom end, she still wants to mono etc when i take off. When people described the low end torque would be lost how much would be lost? ie should it feel slow until you hit x-rpm? If that is the case would i be correct in assuming my main jet is too big? I think they shipped it with a #100...which i imagine may be a touch too large as from memory you had quoted #95 to a few other people.

Bike details PP 140XR, twin pipes, 26mm oko carb, analogue racing cdi
Click to expand...

hey beccs, the difference felt in bottom end loss with the oko's, is usually more noticeable when the main jetting is miles out... eg if you were running a k36-37 pilot, and something like a 110 main... it would feel massively punchy down low, but blubbery up top, then when you get the main jet right, it would feel like it's lost a heap of grunt off idle...
HOWEVER, with a 36-37 pilot, and a 100 main, which is what you have, when you go to a 96 or 97 main, the loss in bottom end grunt and response would be far less noticable...
and yes, your 100 main will be too rich. whilst it will feel like it's running ok to you at the moment, it will feel noticably better once you go to a 96 main... and yeah, it will still want to loft the front... :D

as to the feeling of a ''weak'' bottom end with OKO carbies, you dont actually lose much bottom end grunt or response, if any, when it's tuned properly... due to the OKO's offering epic performance high in the rev range, which comes on quite strong from the mid range up, it makes it feel like it's a bit gutless down low, similar to the power delivery of an 85cc two stroke...

Big thing to keep in mind when jetting an OKO, or any carby on a pit bike come to think of it, no matter the type, is that these are SMALL engines, with limited breathing capabilities... which means that small changes in jetting, will have a large effect... and a main jet being just a few sizes too big, can make the difference between a blubbery pig, and bike that rips when it comes on pipe!!1 :D
 
just popped on a 26mm flattie, and checked the jets. Comes with 100 main.

Going into pretty much stock yx 140

Am I going to be able to get the thing lean enough on the needle as I need it this weekend and getting a 96 or 98 main in time is not really an option. Or do I need to try *really* hard to get one...!?

36 slow, 100main, 140yx stock

Will it work nice enough...?!

** edit - the above post pretty much answered my questions... Carry on, nothing to see here...
 
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I was twisted away from the Minuni carb to try OKO28 on my motard. Doesn't fit on my bike because the frame backbone is too fat :( and no I don't really want to run one of those read angle adjuster thingo-whozits on my bike.. Ooh well my great hopes have been dashed

Why didn't any tell me that it was going to be cold out side in the shed...
 
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no_crf50_here said:
I was twisted away from the Minuni carb to try OKO28 on mine motard. Doesn't fit on my bike because the frame backbone is too fat :( and no I don't really want to run one of those read angle adjuster thingo-whozits on my bike.. Ooh well my great hopes have been dashed
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can you die grind the holes in your manifold to make them into a slot so you can twist the carb/manifold out further?

not sure how much it hits the frame by but you may be able to get away with adding plastic carb spacers between the manifold and carb adapter..

shoot some pics up, theres always a way to make sht fit lol..
 
No-crf there are some pretty sweet 26mm I/D 360 degree stainless manifolds that do work quite well AND seal properly... Had the same problem running the PE-24 on the thumpy.. Easy setup to use and haven't had any leaking issues...
 
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