Author Topic: cb125 single, carb  (Read 1456 times)

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snoop

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cb125 single, carb
« on: March 28, 2007, 09:56:20 AM »
I got the bike and it wasnt receiving fuel. I manualy adjusted my float so the slow jet could recieve fuel. It starts up with 1 kick now.  I went in and adjusted the air screw.  I held the throttle at 2k rpms and adjusted the air screw to where the bike had the highest rpms.  It has a very responisive throttle but wont idle.  So I adjusted the idle screw(this is a screw that physically hits the slide and prevents it from moving down further) and it will idle now.  Sounds great except when I rev it up it will stay in the high RPMs and very slowly come down. 

Should I lubricate the tip of the idle screw so it slide easily on the slide?

Dave L

  • Guest
Re: cb125 single, carb
« Reply #1 on: March 28, 2007, 02:49:13 PM »
HI
I would suspect that the mixture or float is to rich and that the revs drop through to much fuel rather than to little , but you realy need to go with the manuel,
this should not be a hard bike to get running right .
The colour of the plug and its performance should give you a clue

Dave

Offline crazypj

  • I'm brill, me
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Re: cb125 single, carb
« Reply #2 on: March 31, 2007, 01:20:46 AM »
Depending on type of float (brass/plastic) the level could be anywhere between 12.5 to 22mm.
Do you have an air screw or mixture screw?
Air screw is on air box side of carb,before slide and meters air to pilot jet
 Mixture screw is between slide and manifold and meters fuel/air mix from pilot jet
 Mixture screw further out richens idle mix.
 Air screw further out leans idle mix
PJ
I fake being smart pretty good
'you can take my word for it or argue until you find out I'm right'