Oops I did it again, she played with my heart, Lifan 140cc

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Hahaha, such a noob..... I'll try adjusting the other screw tomorrow


Try doing the mixtures too(not sure if anyone mentioned this above). So you need to turn in the idle screw til the idle speed is upto around 1200-1800 rpm somewhere in there.

Bike fully warm(idling at 1200+ rpm) then, turn your mixture screw in half a turn, if it starts to bog. Go back out 1/2 a turn, then another half turn, the bike should pick up in revs(basically you want to turn that mixture screw in or out until the revs pick up), keep turning the mixture screw out until it is at its smoothest revs(will increase in revs one direction either in or out) point ie when its running as nicely as it can be. Then wind the idle screw back in until you reach normal idle speed again! That may help with starting it.

but definitely, check the jets really well on the carby, that they are all clean and you can see through them :thumbup: seems like most older bikes i've gotten have had gunk in the jets! Some worse than others I had a carby the other day start pissing out fuel from everywhere then the bike bogged and died(flooded) All the jets were blocked above the idle jets...hence the problem!

Craig is right about the jets :thumbup: so technically if you have to screw the jet more than 3 turns outwards from 'standard' the jet is to big.

With the mixtures correct you should have to use the choke kick it over it will idle for about 20 seconds then flip the choke back off when it starts to bog down...the bike should be warm enough by then to sit at idle correctly.

I was noob too not that long ago, still am, but learning very fast! Don't worry you'll learn quick, opened my second gearbox today....I pretty much have the internals mapped out in my head now...will be fun the first time I try it without expert help...and I mean fun as in, I'll end up with a sore brain, probably from hitting my head on the wall to many times, getting better at cleaning out carbys etc. Can bleed brakes like a champ now after doing that about 20 times!! Fixed a puncture, that was about my biggest win today :thumbup: after getting the pitpro $70 bike built up and then took it for a run and had no gears after 1st...and lots of crunching :thumbdown: hence pulling it apart!
 
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Bike fully warm(idling at 1200+ rpm) then, turn your mixture screw in half a turn, if it starts to bog. Go back out 1/2 a turn, then another half turn, the bike should pick up in revs(basically you want to turn that mixture screw in or out until the revs pick up), keep turning the mixture screw out until it is at its smoothest(will increase in revs one direction either in or out) point ie when its running as nicely as it can be. Then wind the idle screw back in until you reach normal idle speed again! That may help with starting it.

With the mixtures correct you should have to use the choke kick it over it will idle for about 20 seconds then flip the choke back off when it starts to bog down

Thanks man, the problem that I have is, the idle screw is easy to get at to adjust while the bike is idling, the only way to get at the mixture screw is to pull the bloody carby out..... There isn't much room under there at all....

Ive worked on a few carby's now, but all have been cheap stock China's so the idle and mixture screws are on the side and easy to access, but yeah like u said, any old carby's I've come in contact with have been gunked up, so that was the first thing I did with this one, blew the **** outta it with the air compressor and cleaned all the jets and that, it's nice and clean and can see thru them all now, starts easy now, just not idling and mixing as well as I'd like.

The kid I baugh t it off was using it to do burnouts and that, I don't think he had done much actual riding, and what he has done was go fast, took it for a little ride around the farm today, and it goes alright (although still revving too high and fast) at high speeds, but almost stalls in low gears.... So heaps more tuning yet, and def smaller pilot jet.

Oh, and I found out there was no back brakes..... Will need to flush the fluid and bleed them and see if that helps....

Glad I rode it to find out all these little things.....

I also heard like a crunching sound in the front forks, so will have to do some research on how to pull them all apart and check there is nothing grinding in there or broken, as that's what it sounds like...... This will all be new for me, as I've not done anything with forks before! Eeek.

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Thanks man, the problem that I have is, the idle screw is easy to get at to adjust while the bike is idling, the only way to get at the mixture screw is to pull the bloody carby out..... There isn't much room under there at all....

Ive worked on a few carby's now, but all have been cheap stock China's so the idle and mixture screws are on the side and easy to access, but yeah like u said, any old carby's I've come in contact with have been gunked up, so that was the first thing I did with this one, blew the **** outta it with the air compressor and cleaned all the jets and that, it's nice and clean and can see thru them all now, starts easy now, just not idling and mixing as well as I'd like.

Yeah those carbys are a pain in the bum!! Try using a flat head screw bit and some gloves can sometimes work or you can get a carby spinner thingo to turn it around for tuning!!! Reminds me I still have to do the VM25 mixtures, although I think that carby is near on perfect as it is now....I gave up on the mixtures tbh and pulled the bike apart and just started painting it instead...will do mixtures when needed, even though the 150 is going in that bike when its eventually fixed!
 
Cool, I will have to see what I can do, I have a mate might have a carby spinner....

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Cool, I will have to see what I can do, I have a mate might have a carby spinner....

To easy! Can he make up gaskets as well? So good to have mates who can teach you this stuff :hail:

Yeah I was so noob when I tried the carby spinner I couldn't get it to work properly....but next lesson for me in carbys is flat slide....well d-slide...
 
Dunno, I hope so, he is pretty good with engines and things though, problem is he's a busy man and hard to pin down......

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Dunno, I hope so, he is pretty good with engines and things though, problem is he's a busy man and hard to pin down......

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Free beer always helps....come to think of it I may have to keep my eye out for cheap cartons of diet coke as my teacher of all things engines like that more than alcohol! Probably why he's so good at what he does...

Good luck!
 
Free beer always helps....come to think of it I may have to keep my eye out for cheap cartons of diet coke as my teacher of all things engines like that more than alcohol! Probably why he's so good at what he does...

Good luck!

Good tip, aren't all home based trades based on the currency of the carton! Lol!

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Good tip, aren't all home based trades based on the currency of the carton! Lol!


Nah not quite everyone has bills to pay,but for a beer drinker free beer will get you most things you want(that stuff isnt getting any cheaper)!!! Just make sure you watch closely then you get to learn stuff and will be able to do it yourself later :Thumbup:
 
Had nothing helpfull to add, so heres to keeping thread on topic ;)

[video=youtube;CduA0TULnow]http://www.youtube.com/watch?v=CduA0TULnow[/video]
 
Had nothing helpfull to add, so heres to keeping thread on topic ;)

[video=youtube;CduA0TULnow]http://www.youtube.com/watch?v=CduA0TULnow[/video]

Pre skank stage Britney....yeah ill admit she was rather decent looking back then!!

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Nice one timeeh.... That's where I was going with it.... Lol


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Yeah measure that shock! Ive got this laying around! Will do $100 ono including postage on this one !!! Not blown,fully adjustable...$220 new....
 
Cool....I'll measure tomorrow and check with the boss and get back to u...... :) cheers man!



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Glad to help! Its a nice shock!

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ebu5e9a2.jpg


This is the bike it's going into.... 280mm, 1000lb on it at the moment, with almost no spring in it...

5ymuvunu.jpg


Close up...

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To easy this shock is coming out of the exact same pitpro frame lulz :thumbup: so no worries at all, should all match up perfectly!
 
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