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Discussion Starter #1
My bike has been idling poorly for awhile. I crashed it pretty hard this spring and haven't ridden it since and just figured the pilot circut shellacked up a bit. Well, I pulled the bowl and everything is really clean with no dirt or grime anywhere. I pulled the pilot jet, and was looking on the Easy TK cleaning post and it said that I should see light through the end as well as the side drillings. The side drilling are very clean, but I could not see through the end. I took a small drill and just using my fingers to turn it tried to clear the passage through the bore from the end. No go from either end. It appears to be blocked by brass as though it was made that way. Do any of you have you TK apart and can look? Or are any of you positive. I don't want to drill it through and then find that was the wrong thing to do. TIA. BTW, my TW is a 2003
 

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Step away from the drill bit.....



Soak it, blow it out, probe it with one strand of soft copper wire but no NOT put anything resembling a hardened drill bit through it. If you increase the size of the hole in the process of cleaning it the bike won't run right when you're done.
 

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Discussion Starter #3
Step away from the drill bit.....



Soak it, blow it out, probe it with one strand of soft copper wire but no NOT put anything resembling a hardened drill bit through it. If you increase the size of the hole in the process of cleaning it the bike won't run right when you're done.


Thanks for all of that, but what I need to know is if it is actually bored lengthwise. if so is it a reduced orifice for just that little distance. It is a fairly cheap part from Ron Ayers, but then it might not run until then. Of course it doesn't run good enough to ride right now. If it is just a reduced orifice for that small distance, does anyone know the dimention. I have a numbered drill set and the number on the bottom of the jet is 31, but I don't know if that means .031" of if it is just a Yamaha or TK ID number.
 

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You're correct. The actual orifice is in the end of the jet and is stepped down from the i.d. of the portion with the bleed holes.



It's a #40 jet, but it's a Teikei #40 and not neccessarily a #40 drill size.



Be patient and be careful with it. I prefer to use a Guitar "E" string or remove one strand of copper from a length of #14 stranded wire to loosen the crud after soaking. Personally I never try to clear a dry or hardened deposit without pre-soaking. Tends to cock things like drill bits sideways into the brass.
 

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Discussion Starter #5
You're correct. The actual orifice is in the end of the jet and is stepped down from the i.d. of the portion with the bleed holes.



It's a #40 jet, but it's a Teikei #40 and not neccessarily a #40 drill size.



Be patient and be careful with it. I prefer to use a Guitar "E" string or remove one strand of copper from a length of #14 stranded wire to loosen the crud after soaking. Personally I never try to clear a dry or hardened deposit without pre-soaking. Tends to cock things like drill bits sideways into the brass.


Ok, thanks, I will try soaking it first, but whatever is in there looks like a piece of brass stuck in sideways. I haven't been able to push anything through from either side so far. In the mean time, I think I will just get a new one on the way.
 

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That center/end hole is where the fuel/air mixture is fed into the pilot passageway. Air comes through the side holes, and fuel comes through the bottom hole.







The stock pilot jet in your 2003 is a #31. The end hole is so small that the thinnest carb cleaning wire will not pass through.











Jb
 

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Discussion Starter #8
That center/end hole is where the fuel/air mixture is fed into the pilot passageway. Air comes through the side holes, and fuel comes through the bottom hole.







The stock pilot jet in your 2003 is a #31. The end hole is so small that the thinnest carb cleaning wire will not pass through.











Jb


That's perfect, thanks!
 

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The stock pilot jet in your 2003 is a #31. The end hole is so small that the thinnest carb cleaning wire will not pass through.





Jb


Good call on that. Early slide carbs had the 40's. My bad.
 

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What are you using that #34 on?
I have it in my 2005 TW. It's from an XT250.



I have no explanation, but my bike starts and runs better with the #34. It does run rich, according to the plug color, but does run better, IMO.



I'm not making a recommendation to others. It works for me.



Jb
 

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Discussion Starter #11
lizrdbrth and jbfla Thanks again. I finally did find the hole (I think lack of hair was the problem), it was plugged solid. Just about anything that might get through could plug that tiny thing. I do have a filter in line, but I suppose a bit of hose or o-ring could still come loose and get in there. Anyway the bike is running perfect again and I appreciate your expert help.
 

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.... Just about anything that might get through could plug that tiny thing. I do have a filter in line, but I suppose a bit of hose or o-ring could still come loose and get in there.
It's my theory that crud gets sucked into the carb through the carburetor air vent, which has no filter on it. It needs one.



There is a screen on the petcock, one in the inline fuel filter, and a fine screen on the needle valve seat.



There's no way the black specks of crud in this bowl could get through all those filters.









Jb
 

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I think you're correct. I use weedwacker fuel filters on my vents. Hardly ever get sediment in the bowls.
 

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I think you're correct. I use weedwacker fuel filters on my vents. Hardly ever get sediment in the bowls.
Thanks for the tip. I'll give it a try.




Jb
 

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It's my theory that crud gets sucked into the carb through the carburetor air vent, which has no filter on it. It needs one.



There is a screen on the petcock, one in the inline fuel filter, and a fine screen on the needle valve seat.



There's no way the black specks of crud in this bowl could get through all those filters.









Jb
Great info guys! Seeing that a picture of the main jet splash ring has been posted, I was wondering how important is it?

When I got my '94 there was quite a few spare/extra parts. One of the parts I received was that splash ring. I don't know if it's a spare or the previous owner forgot to put it back in. The bike, once it's warmed up, runs great- with a 20% choke. It kinda bugs me but if that small amount of choke is all it takes to run well, I'll have to wait 'till I have some real spare time to mess with it. TIA OM
 

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...Seeing that a picture of the main jet splash ring has been posted, I was wondering how important is it?....
The pick-up end of the main jet sits in the middle hole of the splash ring. The splash ring keeps fuel around the end of the main jet from sloshing back and forth.



On smooth pavement the splash ring may not be absolutely essential. The engine will run without it.



On rough, off road terrain, or in any situation where the bike is bouncing around, without the splash ring, there may be an inconsistent draw of fuel through the main jet, causing the engine not to run smoothly.



Needing to use the choke after the engine is warmed up, indicates that the engine isn't getting enough fuel through the pilot and main fuel circuits.



Jb
 

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The pick-up end of the main jet sits in the middle hole of the splash ring. The splash ring keeps fuel around the end of the main jet from sloshing back and forth.



On smooth pavement the splash ring may not be absolutely essential. The engine will run without it.



On rough, off road terrain, or in any situation where the bike is bouncing around, without the splash ring, there may be an inconsistent draw of fuel through the main jet, causing the engine not to run smoothly.



Needing to use the choke after the engine is warmed up, indicates that the engine isn't getting enough fuel through the pilot and main fuel circuits.



Jb
Great, that gives me an idea on how it works. There may be one in there- I haven't had the carb apart to check. I'm sure it could use a good clean-out. OM
 

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....I have no explanation, but my bike starts and runs better with the #34. It does run rich, according to the plug color, but does run better, IMO.

Jb
Actually I do have an explanation.... about using the #34 pilot jet.



I was having starting problems, and thought a pilot jet that would allow a bit more fuel at idle might help.



It didn't. The problem turned out to be a faulty ignition coil.



Once I replaced the coil, the bike ran so good I decided to leave in the larger #34 pilot jet.



I did adjust the idle mixture screw in about 3/4 turn.



To repeat, I'm not making any recommendations. To paraphrase Lizrdbrth, not having the idle mixture screw adjusted properly for your specific bike, may only be compensating for problems with other parts of your carb.



Jb
 

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I think you're correct. I use weedwacker fuel filters on my vents. Hardly ever get sediment in the bowls.


Sorry,but...a weedwacker filter in/on your carb vent. Any site's or pictures so I'll know what I'm looking for?.....my weed wacker is battery operated. TIA
 

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