Non consistent running engine?

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It was the jet needle in a too rich position .. Couldnt even remember moving it I had to double cheack my bros one to make surei actualy did move it, it's back on the middle clip position and now is now running back to normal
 
Could have sworn that was it, but this high rpm cutt out is back? I changed the plug and the old one was black, ( probably from the richer clip position..) seemed to fix it, but then back again. Going to do the valve clearences tomorow, because I did just put a exhaust valve from a difrent lifan 125 in and it looked a lot newer than the old one andim thinking it could have lost its clearence, It shouldn't be the stator because I oly replaced it half a year ago due t the old one getting belted by my chain
 
Because i dont have a multimeter i could switch the stator coils with others I have and just test them, it shouldn't be the ignition coil because I just baught that like a week ago, is that what wears on the stator though? The coil things ?
 
it could be the stator,
but with it cutting out when your riding, i'd be trying another cdi in it.

if you were to ride it each day on the same track, would it cut out at the same spot ?
or is there a bump, a hard corner or something you go over/around and it cuts out ?
 
Yea basicly ay not as much the same spot on the track but every time I hit a certain rpm (fairly high),I'll try my brothers CDI today. But it is Way older than the onion my bike, so is the stator for that matter.. But yea like Tim just said his only lasted 4months., so I supose I should try changing the CDI, and stator coils. It starts first kick, sounds completely normal.. It will even not cutt out if. Am lucky in 4th on a big straight.. Most of the time, I'll get to 4th because I can't use high rom in 3rd because of the Cuttout, and it will get to top speed then start cutting out really bad, I will re cheak the plug i put in yesterday to see if it has gone black, but it shouldn't have. Seing as I moved the needle clip up one (lowering it), if it is black what could that mean? I will also be checking valve clearences and cam timing today but I highly doubt either are causing this problem
 
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Is this why people hate china bikes? Because their stators, cdis and could last f all? Taking an guess pitpro is a china bike right?
 
My brother said it went hard just like his after I did all that stuff from loud pop band lifan thread, eg helicoil, replaced bent valve, changed ignition coil.. As far as I'm concerned it did go hard after that, up untill I went through that fence. So I'm thinking going though that fence has f'd somthing? ..
 
It sounds like a blocked emulsion jet to me.
Pull the fuel bowl off, and remove the main jet.
Poke a strand of wire through it a couple of times then blow it out.
Now the brass jet where the main jet screws into in the base of the carby, remove that with an 8mm spanner and take it out.
check the hole thoigh the middle is open, and the 12x holes that go across the jet are all open.
poke a strand of wire though them to make sure, and blow it out.
before you refit those 2x jets, blow though the base of the carby where they screw into, incase there is anything in there too.
now reassemble the carby and try it out.

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If i hated chinese bikes i wouldn't be here!
They are just as reliable as a Jap bike, especially when they are looked after and maintained/serviced regularly.

half the faults you may have come across could well be caused by the user from what i've read.
 
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Already did that yesterday, but il re do it anyway.. The inlet valve had no clearence so I'll be trying it agin soon with.004"

I know Almost everyone on this site loves them, I have seen ktms and kawis in worse shape than china Ike's from the same track. But I'm talking about the quality of the ignition system, are they pretty crap compared to jap bikes or are they pretty good... Hope it's just the loss of clearence doing this cutt off at high rpm though and not the electrics. Carb should be okay though, only did it yesterday and have been keeping the air filter clean.. Not oiled because it's not a foam filter
 
Your Air Filter need's to be oiled, paper or foam.
with no oil on it it can let dirt/dust etc get through and into your carby/engine
if will also run too lean and could cut out at higher rpms


Having valve clearance's tight/closed will make the bike harder to start, and won't run as good as it can.
If left like that it will do damage to your engine.
 
Do you mean rich or lean? Because wouldn't a un-oiled air filter make it run richer ? And my sparklug is still on the dark side
 
Yeah that makes sence, wouldn't want it any richer than it is so I'll leave it in-oiled and test it when I take front brakes off or find a long enough bolt to put them on
 
Ok, i'm not sure how that relates to hitting a fence? lol

I was sure you said that you had adjusted the valves, and they were good
 
It dosnt, that's just the last time it felt like it actualy went properly, a bigg stall could have slightly bent the rocker arm mabey? Turning 0.004" into0.000" I adjusted them then had do do my bros clearences and a few things to my bike before I Could test it, I just posted that to clarify the what was causing the problem. S mabey someone who is having the same problem can use it as a reference. I know it was dam hard trying to find a clear 'do the gave clearences and it will go away" on the net everything I could find n the subject was different
 
Nah, there is no way a backfire can cause a rocker arm to bend .
An engine running at 6000 tpm is putting well over 100 times that pressure onto the rocker arm, compared with a backfire
And even if it could happen, it would open up the gap more, not close it.
 
Not a back fire, s big stall. But yes ours right, even if it could it would have bent it the other way, must have just been a coincidence that it lost its clearence then...
 
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