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Hello All,

Ok I have a 82 xt 125. The idle was high so I cleaned the Carb and soaked it. Put everything back together and fired up on the third kick. Now I have an issue with gas coming out of the drain on the bottom of the carb. The bolt is new and the o-rings are as well. Does anyone have any ideas why this would be leaking out? Also my high idle is back as well. Would this be causing that assume?

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Either the float is stuck or the needle and seat are bad. Try lightly tapping on the side of the float bowl, if that doesn;t work you can try to clean the needle/seat and reset the float level or replace the needle/seat.

Basically, when the bowl fills with gas, the float floats up pushing on the needle (pointy part) into a cone shaped recess in the seat, ultimately shutting the fuel off. When the engine uses the fuel in the bowl, the float comes down opening the needle/seat to let more fuel in. Setting the float to the proper level keeps the correct amount of fuel in the bowl so 1) the engine doesn't starve for fuel and 2) so the fuel doesn't overflow out of the carb.

A dirty or worn needle/seat will not shut off correctly allowing fuel from the tank to constantly flow.

needle&seat.jpg

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+1 on all of the above................also, if you have an all-metal needle you might be able to get away w/ lapping it into the seat w/ some fine valve lapping compound, rubbing compound, or even polish if you have the time. I've gotten away w/ this on older bikes where the needle/seat was either unavailable or wicked expensive.......if it's all metal.

Your high idle may be from the high fuel level in the bowl; it oughta go away if everything else is clean and adjusted properly after you fix the float-needle issue.

If the bike has a metal tank, you may have chronic issues w/ leaky float vlaves from rust flakes holding the needle off-seat. An in-line filter will keep the larger chunks from getting down to the needle.

Edited by HodaddyB
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thanks all for the advice. I got the gas dripping problem fixed. However, now im running really rich. I took the carb back apart and blew the needle back out. I thought maybe since I had clean the needle that maybe backing off of it some would help. That worked but im still running rich. I went a 1/8 turn and now just another 1/8 turn. Once above 3rd gear it wants to start running rough. Anyone have any ideas? Also does anone have really good instructions on adjusting the float. I have seen on the interent but it seems like everyone has a different idea. Thanks again for eveyones help!!

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Have you removed and cleaned the needle jet?

If you don't, the fuel will not atomize properly and you'll also draw in too much fuel. Generally the main jet holds the needle jet in place. Once the main jet is removed, you simply push the needle jet out from the carb bore side. There ought to be some holes in the side of the needle jet.

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It would also be worth ensuring the air passages to and from the needle jet area are clear too. If you put your finger over the hole in the carb bore where the needle goes into and spray alcohol/brake clean/contact cleaner/even WD-40 into where the main jet screws in, you have it come out of the hole in the carb flange (where the air filter mounts) and it should also come out of the tiny holes in the carb spigot, on the engine side of the venturi. If these aren't clear you'll also pull too much fuel.

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Also does anone have really good instructions on adjusting the float. I have seen on the interent but it seems like everyone has a different idea.

This is the way I did the 4 carbs on my 900. To attach the clear tube I removed the bowl drain, then used the tip of a PaperMate pen and threaded it into the hole. I then used the other end of the pen to attach the tubing.

Pic makes more sense.

IMG_8960.jpg

clear_tube_combo.jpg

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I've always just measured the float height from the float-bowl mating surface, but not all manufacturers use that method, and some designs/tech data leave you guessing where to pull the measurement from on the float. They usually are looking to have the "hinge" area of the float parallel w/ the parting surface of the bowl/body.

If your tech data provides the measurement for Jeekins' method, it is by far the most accurate way to determine what your fuel height will be w/ the carb mounted. Most books I've seen provide a fuel height spec.

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Ok, since my original post I went ahead and adjusted the float along with the main jet. I have fixed my problem with it missing in 3rd gear or higher at about 35mph on the throttle. Now though my new problem is in first and second off of a take off. Any ideas on this? Or did I over adjust something? Thanks again for eveyone helping out.

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If you have tech data for this bike and have not modified anything, a clean carb w/ the nominal jet sizes and settings should be darn close.......Florida humidity notwithsatnding.

Is there anything about this bike that's non standard? What do you mean by "adjusted the float along with the main jet"?

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The bike is completley stock. I'm at a lost right now because I can not figure what im doing wrong. It is still running ruff in first and second. It is also running ruff at a constant half acceleration. On the main Jet I see it is adjustable. What is the common adjust on the main jet? Thanks again for everyones help!!

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I post this here becuase it is enduro. It is mainly ridden on the street since I purchased it. I did not change the main jet it the same one. All i did is back the jet out some thinking that would how my running rich problem.

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Hmmmm, unless Yamaha did something kooky (and the '80s were a kooky time for Yamaha in particular), your main jet ought to be just like any other main jet - a piece of brass that either screws into the needle jet or the portion of the carb body that holds the needle jet. It shouldn't be adjustable. If it's anything but screwed in snugly it'll most likely fall out into the float bowl.........causing poor running.

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I just took a look at an online fiche and it appears that your carb (if your bike has a stock one) is a pretty standard rig. The main jet certainly doesn't look adjustable. The weird thing about it, but not for the '80s, is that it does NOT appear to have a pilot screw. The good news is that it's one less adjustment to fiddle with, the bad news is that to make any adjustments, you have to swap brass. If your bike was running fine, but now it's not, you may still have a dirty carb. If you are absolutely positive that it is indeed clean, you may have another issue. But something is definitely fishy if all you have told us is accurate. If you haven't owned this bike for its entire life, anything can be possible in regard to what you have for a carb, and then all bets are off concerning what your solution may be.

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