2 Stroke CR 125 01 Fouling spark plugs

O

ossagp

scroll up. but i still think that it is more than jetting as you are pretty much on stock jetting and the flooding and fouling seems on the extreme side. if i was buying a jet it would be no larger than 50 though.
 
M

madguru100

ossagp:
scroll up. but i still think that it is more than jetting as you are pretty much on stock jetting and the flooding and fouling seems on the extreme side. if i was buying a jet it would be no larger than 50 though.
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Do you think its a float leak? Well i it wouldn't foul instantly but when i deaccelarate it starts fouling you could hear it not going through the rpms after 20 minutes of running time it fouls . I'll get a 48 jet ? or? thanks
 
Mihylo33

Mihylo33

I'm reading through this even tho I didn't post just to follow and see where we end up. If I remember correctly it was owned by an ex racer, correct? Now when I raced a small bore as a kid my dad mixed oil heavy and jetted fatter. @ossagp is it possible that previous owner ran his mix at say 24:1 and has it jetted correctly for that ratio?
Just a thought.
 
M

madguru100

Mihylo33:
I'm reading through this even tho I didn't post just to follow and see where we end up. If I remember correctly it was owned by an ex racer, correct? Now when I raced a small bore as a kid my dad mixed oil heavy and jetted fatter. @ossagp is it possible that previous owner ran his mix at say 24:1 and has it jetted correctly for that ratio?
Just a thought.
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Yea it was owned by an ex racer he might of jetted it that way but that's just too much oil
 
Mihylo33

Mihylo33

madguru100:
So i should try to put more oil in it ? Even though there is a lot of spooge coming out of the exhaust header i bought the gasket i'm awaiting it
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Merely speculation on my behalf. Without the bike right in front of us we can only give our ideas and opinions on what might be wrong. Ossa is guiding you in the right direction and working you through it. That's the right way. I just thought I would add a thought I had so he could take it into consideration rather than chase a ghost.
 
M

madguru100

Mihylo33:
Merely speculation on my behalf. Without the bike right in front of us we can only give our ideas and opinions on what might be wrong. Ossa is guiding you in the right direction and working you through it. That's the right way. I just thought I would add a thought I had so he could take it into consideration rather than chase a ghost.
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Yea true well i'll try the choke knob and jetting first thanks mate
 
O

ossagp

Turning down the choke knob treats a chronic problem with this carburetor. You have no chance at idling but its pretty easy to deal with. The way I test for leaks at the float is to put enough hose on the carburetor that I can hold it up and see the float mechanism well and blow into the fuel inlet line while I hold the float in the same position you set it at (16mm) you should be able to shut the airflow off right at that point rather easily. see if it is leaking. It isnt fool proof. Under vibration they can still leak a little.

Oil in your mix can amount to about half a jet size (when you compare 20-1 with 50-1), and in this case amounts to fine tuning again . So for now work on the mechanicals of this critter would be my suggestion.
 
M

madguru100

ossagp:
Turning down the choke knob treats a chronic problem with this carburetor. You have no chance at idling but its pretty easy to deal with. The way I test for leaks at the float is to put enough hose on the carburetor that I can hold it up and see the float mechanism well and blow into the fuel inlet line while I hold the float in the same position you set it at (16mm) you should be able to shut the airflow off right at that point rather easily. see if it is leaking. It isnt fool proof. Under vibration they can still leak a little.

Oil in your mix can amount to about half a jet size (when you compare 20-1 with 50-1), and in this case amounts to fine tuning again . So for now work on the mechanicals of this critter would be my suggestion.
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Do i first set the 48 pilot jet in the carb then turn down fully the choke knob ? Apparently you can test to see if their are any float leaks by putting them in boiling water and see if air escapes from them thanks mate
 
O

ossagp

Not the kind of float leak I was talking about. AGAIN before replacing parts I would work with the ones there. So I would simply start by screwing the knob down and riding off.

I test the floats for leaks in the buoyant lobes by placing the float assembly in water and seeing if the float level from side to side. Shake them and see if you can hear liquud in them etc. None of that tells you if you are keaking fuel at the seat or behind the seat in the sleeve that I believe I mentioned.
 
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