2 Stroke 2003 CR 125 help

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Tonystarks

Hey guys I'm new to this forum, a few months back I bought a 2003 cr 125 (first bike ever) for 1400 dollars. I take the bike home it blows up on me not even 20 minutes in. Long story short it has a fresh bottom and top end built by a good friend who has built many bikes before. Started up after fiddling with the carb for a while and got it running. Broke it in for a while and then it fouled a plug. A few days later I come back to it with fresh plugs, air filter, throttle cable, and refurbished carb. Now it won't start. Tried jump starting it and it just purs a little and dies. Me and my buddy are lost, if anybody has any suggestions I'd greatly appreciate it.
 
T

Tonystarks

MikeinFresno:
see if it has spark with another NEW plug, if it does then dribble some gas in the spark plug hole, quickly put plug back in and try to start it.
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ossagp:
When you take the plug out after trying to start it, what does it look like? Wet, dry, black, oily etc.
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It has spark and the plug still looks new, i even tried switching it out with an another new one for good measure. I'm going to pep boys today for some carb cleaner and i'm going to try the whole carb/ float thing out.
 
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ossagp

So new and dry looking. Sounds like fuel is not getting where it is suposed to be.
Memory tells me that one has a Mikuni carburetor. The needle jet and holder assembly is removable on that one, if so. Therefore it has to come out and be cleaned too.
 
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PawPaw

Is the gas turned on at the tank?
Is it flowing to the carb?
If you lean the bike over to one side does fuel come out of the carb over flow hose?
If yes to all the above...Pull and clean the pilot jet.

Paw Paw
 
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ossagp

If the plug is coming out dry especially after a failed push start attempt, my thought of it being very very flooded is out the window, something I would have almost bet on after fouling a plug and putting it away for a few days.
 
T

Tonystarks

ossagp:
So new and dry looking. Sounds like fuel is not getting where it is suposed to be.
Memory tells me that one has a Mikuni carburetor. The needle jet and holder assembly is removable on that one, if so. Therefore it has to come out and be cleaned too.
Click to expand...
PawPaw:
Is the gas turned on at the tank?
Is it flowing to the carb?
If you lean the bike over to one side does fuel come out of the carb over flow hose?
If yes to all the above...Pull and clean the pilot jet.

Paw Paw
Click to expand...
ossagp:
If the plug is coming out dry especially after a failed push start attempt, my thought of it being very very flooded is out the window, something I would have almost bet on after fouling a plug and putting it away for a few days.
Click to expand...
I'm over in Pa right now with some family i will try the above when i return. Thanks again for the help.
 
T

Tonystarks

Just an update.... cleaned the shit out of the carb put it back in and got it running again. Problem is it pisses gas even when running and also whenever I turn right the revs sky rocket (maybe faulty throttle cable) ?
 
SRAD97750

SRAD97750

Moderator
Staff member
Tonystarks:
Just an update.... cleaned the shit out of the carb put it back in and got it running again. Problem is it pisses gas even when running and also whenever I turn right the revs sky rocket (maybe faulty throttle cable) ?
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Float is not set right, dirty, or the needle has deteriorated.
Fuel level is controlled by the float alone.

The engine revving up in a right turn only is a cable routing issue. Something gets too tight when you turn it right.
-BIG DAN:thumb:
 
T

Tonystarks

SRAD97750:
Float is not set right, dirty, or the needle has deteriorated.
Fuel level is controlled by the float alone.

The engine revving up in a right turn only is a cable routing issue. Something gets too tight when you turn it right.
-BIG DAN:thumb:
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Mihylo33:
Yeah what Danno said!
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Fiddled with the float a little bit and its working just as it should now. And with the routing of the cable it seems to be the most optimal route but i will try another way. Thanks again guys you were a big help!
 
Mihylo33

Mihylo33

Tonystarks:
Fiddled with the float a little bit and its working just as it should now. And with the routing of the cable it seems to be the most optimal route but i will try another way. Thanks again guys you were a big help!
Click to expand...

Make sure that the cable is properly seated into the carb and that it has the correct slack.
 
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