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Fuel dumping out of carb, float level is properly set 03 CR250. Whats the issue?

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I have had the float level set to the proper level and I am still leaking a lot of fuel out of the small hose at the bottom of the carb. 

 

Its an 03 with the TMX (which is dialed in and running great fwiw)

 

I am considering putting on a longer hose and making a loop or two with it... before I run it out by the rear shock.

 

 

Unless somebody has some a better idea as to why this is happening and how to fix it? 

 

Thank you! 

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double and triple check the height, or the needle and needle seat need tobe replaced because its not sealing shut anymore.

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Replace the needle and seat as mentioned above then set the float height again.

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double and triple check the height, or the needle and needle seat need tobe replaced because its not sealing shut anymore.

 

Which # exactly refers to the two parts you are referencing? 

carb break down.PNG

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Your actual float could have taken in some fuel not allowing it to raise up high enough to seat the float pin, I have had that happen before.

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I have a 2004 cr250 and it does the same thing, it will leak sometimes and not other, but hasn't done it lately so it leads me to believe it probably my fault. Two days at the track and not once did the carb leak, so I think it might be a couple of things. It can be an engineering flaw since this issue is posted all over the net. I think personally think it is due to the velocity or the flow rate of the fuel. Race fuel flows with very little gravity. If a little fuel flows out one of the sh$t tubes it will continue to flow. Some people will say that can't be because the float should cut off the flow, but if gas is coming in at the same rate it's leaving the hight of the float would stay the same. I find if I let the engine come down to idle and let it sit for a second and then shut it off it stops this suction effect. I now shut of the fuel valve as much as possible as it the only way to be sure it doesn't happen. Just one of joys of owning a CR.

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The o ring around the brass fitting that the float needle goes in to can shrink up. Try replacing it.

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The o ring around the brass fitting that the float needle goes in to can shrink up. Try replacing it.

I completely rebuilt my carb, replaced the valve/seat/oring with OEM parts and the float height is correct, carb still does it. Even replaed all the vent hoses with new OEM hoses, routed per manual. After all that, I think it does it worse that when I saved the bike from a bar, hadnt been rode in 10 years

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Basically two kinds of late model CR owners.  Those that have gone through these issues and finally ditched the Mikuni for a PWK, and those that will.  Of course there is always an exception.

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Basically two kinds of late model CR owners.  Those that have gone through these issues and finally ditched the Mikuni for a PWK, and those that will.  Of course there is always an exception.

 

So you are telling me Honda designed their bike to puke out all it's gas because of poor design? I find that hard to believe. 

 

BTW, my TMX Mukuni is dialed in just as good as the PWK (actually a bit better overall) was when I had it on my bike. S7 nozzle did the trick. 

 

I will try replacing those two parts. I am also going to check the fuel lines and in tank filter to ensure that there isn't any crud anywhere. 

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So you are telling me Honda designed their bike to puke out all it's gas because of poor design? I find that hard to believe. 

 

BTW, my TMX Mukuni is dialed in just as good as the PWK (actually a bit better overall) was when I had it on my bike. S7 nozzle did the trick. 

 

I will try replacing those two parts. I am also going to check the fuel lines and in tank filter to ensure that there isn't any crud anywhere. 

 

No, that isn't what I'm telling you.

 

I'm just saying that the PWK doesn't seem to have the many issues of the stock mikuni.  I have two CR's.  Both stock carbs are in a drawer.  I run PWK's on both bikes.  No issues anymore.

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No, that isn't what I'm telling you.

 

I'm just saying that the PWK doesn't seem to have the many issues of the stock mikuni.  I have two CR's.  Both stock carbs are in a drawer.  I run PWK's on both bikes.  No issues anymore.

 

So how do you explain all the "How do I jet my PWK" threads that have been popping up lately?

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So how do you explain all the "How do I jet my PWK" threads that have been popping up lately?

 

There's plenty in info out there already.  And jetting options continue to evolve as folks experiment with different needles and slides.  Keep in mind that changing carbs to something non oem means no oem specs or support.  What threads are you referring too?

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So how do you explain all the "How do I jet my PWK" threads that have been popping up lately?

 

This is one reason why I went back to the TMX. S7 nozzle and race gas. There are factory specs for it, where as the PWK is a guess. 

 

Honestly there may be too many variables for some people to properly jet in a bike that does have a more finicky carb than others. Not that I am pro or expert because I had to get help dialing mine in. Once I got it though, it was just as good, if not better then the PWK I had on the bike previously. 

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Go to jd jet.com they sell new pwk carbs and will install the correct jets based on your area and riding stile. This option takes away any of the guess work and is the plug and play option. I believe they also sell matching throttle cables. The carb with the jets are $250. I think they also might have a pwk carb that allows the tps throttle position sensor to just be plugged right in. With out the tps the bike is has the ability to bog when under load at low rpms. This will be noticeable when a rider gets tired a stops working the clutch.

While your in there put in some new reeds, if you really want to finish off the job get a boyesen exhaust flangy and a 304 PC pipe. Then all you have to do is hold on because the bike becomes a rocket. I put race gas in mine just to calm it down.

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While your in there put in some new reeds, if you really want to finish off the job get a boyesen exhaust flangy and a 304 PC pipe. Then all you have to do is hold on because the bike becomes a rocket. I put race gas in mine just to calm it down.

 

Haha

 

Wut 

 

Not sure if trolling on that race gas part.... 

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