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Discussion Starter · #1 ·
hay so can some one explain to me what todo to my bike as when i checked the spark plug its black and oily so can you walk me throuh how to limit the fuel and also do the idle as well and also does anyone know where i can get the carb gaskits from?
 

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hay so can some one explain to me what todo to my bike as when i checked the spark plug its black and oily so can you walk me throuh how to limit the fuel and also do the idle as well and also does anyone know where i can get the carb gaskits from?
Sounds like you need jets and a bowl gasket but its possible you have the float set too high[rich]
 

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Going to need a jet kit. There is the choke jet which I believe is permanent, pilot jet and main jet, and the 5 slot clip on the carb needle. Alot of adjustments. It's hit or miss, my 50cc, ( 46cc ), has the 19mm rep carb, and I am running a 1.01mm main jet, atleast 6 sizes bigger than stock, the biggest jet in the kit.
 

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Discussion Starter · #7 ·
right ill explain what happend

i was runing the bike the engine wos fine and very fast then as time went on about 25 mins in to runing as i was going alone then opend the throtle up it sort of boged down like a flat spot but befor it didnt do that and it was fine?

i know its runing rich so ill do the air/fule scrue and the idle as well but any idears what it could be as it wos fine before when i wos runing it in?
 

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Discussion Starter · #8 ·
just found this is that right? and should i do it?

How to adjust and select idle jet and atomizer.

1.Remove carburetor from box or bike and write down all jet, needle, and atomizer settings and part numbers.
2.To set your idle speed screw, look into the engine side of the of the carburetor's bore. Turn the idle screw counter clockwise until the slide is just closed. Now turn the idle screw in 1 1/2 turns.
3.To set the brass idle mixture screw, turn it in all the way in slowly BUT not tight, just until it touches the bottom, then turn it out 2 1/2 turns. This is just a base setting and you will need to fine tune it later.
4.Install carb: pull the choke and start it up. Count to seven and turn off the choke. Let it warm up.
5.Now give it 3/4 throttle than let go.
6.What you want is the motor to settle right down smoothly without it hanging on to the rev's or loading up.
7.Now turn the mixture screw till you get a nice snap and set idle speed
8.If the low speed idle/jet mixture screw gets lower than 1 turn out you need a smaller idle jet and if it gets higher than 3 turns out you need a bigger idle jet.
9.Now do full throttle range plug chops to set an select slide needle and main jet.
10. Repeat steps 5 6 7 8 9.

NOTE if the idle jet gets smaller than a #38 you might need a leaner atomizer or steeper slide with bigger vent holes. If the idle jet gets bigger than a #52 you might need a richer atomizer. And if your idle speed screw is more than 3 1/2 turns in you might need a higher number slide, like a #40 with it's steeper angel and bigger vent holes. Needles with longer tapers are earlier because they begin to meter the air fuel mix at a lower throttle position, Needles with a shorter taper are later because they begin to meter the air fuel mix at a higher throttle position, The AU 260 – AU 262 or AU 264 atomizers and AU bushing fix most PHBG. Most 19mm to 21mm carbs will need a #40 slide, W9 – W3 - W7 or ? some carb setups if you use a W7 it can be to lean with the clip in the top/leanest notch. 17mm #30 slide 18mm carbs will use a #30 or #40 slide and use W7 – W4 or ? on smaller carbs 30 or 20 Slide or ? And check your float the 2 stroke one is the lighter one p/n 9450.1 - 4 grams. The p/n number's or on the floats. Every set up and combination will be different to tune in.
 

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Id try resetting the float first...Set it a tad leaner so the fuel doesnt get so high in the bowl...it may be set too rich and flooding the engine as the bike runs and leans when riding............
 

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Discussion Starter · #10 ·
so just tern it in 3 and half terns and see if that is cool on the spark plug right im suer you said that ?
 

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Discussion Starter · #12 ·
okay so bend it to the lets say seat? so up right and also is that a 19mm rep carb? my air fillter is a sbunge one i wont a k and n one like yours?
 

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Yeah, it's a rep carb, both me and Cam2 have tried to make that carb work on a Cag engine. That's what you see in the picture. Nightmare, they work better on the W/C 2 strokes, but got to run them rich cause there is alot of air differences from 12mm Cag and a 14mm Dell to 19mm.
 

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Yeah my carb was installed on a 5 port cag with 14:1 compression running a top speed of 45mph with my bro on it geared 7/47...........

It took some time to get it dialed in but its definately a very tempermental and twitchy carb......I blueprinted mine and stuck it on my PW80.......runs like no PW youve ever seen with all the other mods done to it which basically turned a 26mph 3 speed semi-auto into a semi auto YZ hitting 42.........LOL

 

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Perfect for an 80cc bike. I have done that many times, get a carb for one bike, and it don't work, and you put in on something else and it works great,lol.
 

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Perfect for an 80cc bike. I have done that many times, get a carb for one bike, and it don't work, and you put in on something else and it works great,lol.
Yep and thats better when that happens......LOL...Then you dont feel like you wasted money or stockpile them for posterity.........LOL
 

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Discussion Starter · #17 ·
so maybe i should get a carb thats better right anyidears of any that are really good and not so tuchy

iv just found out that evan if i get the rich or lean right that when i use top tend its completely diffrunt and that theres 3 jets whys the mix scrue there if it dosnt do much?

im wurryd that if i get it right and then do top end all the time that it will blow sorry for spelling also if you could help me i wont like a plan of the carb so i can see how to pute it back to gether but all the ones i found look so pore like thay have bean made with a scanner so cant see where bits go

the air filter the spoung one that came with the carb didnt before i did the run on the bike but arfter it i sore its sucked the spong away so would that do anything? cuz it would have bean sucking air thru the hole right?
 

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Could be a coil not working right at top speed. What size is your main jet?
 

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Discussion Starter · #20 ·
well i have no idear or how to find that out im wurryd that if i take it apart it wont go back together haha also you might be right about the coil iv bean told thay dont larst 5 minuts and that to buy a polini one is best as the china ones burn out and the polini ones let you have more revs maybe thats it
 
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