Crf80 wont rev

[blkwdw]

Having problems with the carb on my daughters crf80. It will start and can eventually get it to idle but give it a rev and it dies when the revs come back down instead of idling. Also it won't rev out.
At first at half throttle it would rev right out but any more or less throttle and it would rev not far above idle and sound ****. We raised and lowered the clip on the fuel needle and each time it ran worse so we put it back to the centre groove. All jets are clear and no dirt in carby. Float level is what I'm hoping is the problem.
At first the fuel would piss out the overflow. So I bent the flap and no fuel came out. We then got it so fuel dribbled out but still having same problems. How quick should the fuel come out?
Bike has a new plug and clean fuel and new stator and cdi. Plenty of spark. Air filter is clean. Played with the fuel mixture screw and it didn't change a thing.

Will note the bike ran fine before putting on the new stator, cdi and carby. Could the timing possibly be out as the stator originally on it had 3 wires with 2 of the wires joining near the one of the plugs but the new stator has all 3 wires seperate and one of them not plugged in as there is now where to plug it in.

 

[my67xr]

what year is the bike and the carby ?
and what model carby is on it ?

 

[blkwdw]

The bike is an 08 model and the carby is a kein or however its spelt carby

 

[my67xr]

ok a Keihin, so what i your float height set at ?

 

[blkwdw]

No idea. I just bent the tab up to stop it overflowing but bent it to far and no fuel came out. I then just u bent it until fuel steadily came out.

 

[blkwdw]

Carby model PC20B CKJ7

 

[my67xr]

with the fuel bowl off,
the float should be sitting almost level (slightly lower), and the tab just touching the tip of the needle (needle and seat)

 

[blkwdw]

Ill hav a look when i get back home. Ive tried finding specs on the carb but having no luck. The carby isnt even listed on the keihin site. Will this be the cause to my problem though?

 

[my67xr]

the float height governs how much fuel can get through the Main jet,
and at what ratio the fuel mixes with the air

 

[my67xr]

here is a basic tuning guide for the Takegawa/Keihin PC20
http://www.takegawa.co.jp/files/03-05-024.pdf

 

[blkwdw]

Played with the float height today and it didnt change a thing. If it was running fine before and all i did was change the carby, stator and coil lead surely it cant b anything else

 

[my67xr]

if the bike was running fine before, why did you swap the new parts onto it ?

with it stalling after revving, it sounds like the Pilot jet might be too big, or the mixtures are very rich?
have you compared the size with the one from the original carby ?
how many turns out is the mixture screw ?

 

[blkwdw]

I bought 2 bikes. An 97xr80 and a crf80 both cheap as they were both needing parts and the xr needed more. The crf was runing just needed new plastics. I took all the parts of the crf to put on the xr80 to get it running so i sell it. I didnt want to put new parts on the xr since i was selling it and keeping the crf so wanted the new parts on it. I had the problem with the carby on the xr80 so swapped carbies so i could quickly get rid of it which i did. That meant i needed a new stator and backing plate, coil, clutch cable and lever setup etc etc. now we pulled the brand new plug out and it was black as and since the bike hasnt been ridden with it im guessing thats a sign of to much fuel. Theres is also blackish smoke coming out exhaust which it never did before. Float levels havnt changed a thing. Dont know if u can change the timing. The more u rev it the worst it gets until it dies.

 

[blkwdw]

I know what the problem is. I dont know anything about carbies so couldnt tell what should and shouldnt b in there. The main jet i thought i was looking at isnt the jet. Its the jet needle holder. After getting an exploded view of the carby i have found its missing the jet holder and main jet itself. Wish i had picked up on that earlier but now i know whats wat in a carb.

 

[my67xr]

yeah, ^^ that'd do it, lol