XR Carb help

I don't know nearly as much as I'd like to about my carb ('95 XR600R).

I went ride this morning and when I turned on the fuel, noticed a steady stream of gas running out of the overflow tubes from the bowl (?? the bottom part of the carb).

I fiddled with the throttle for a minute and removed the drain bolt from the bowl. As soon as I turned the fuel on again, gas just poors out of the bottom.

I rode the bike hard for hours last Saturday without any problems at all. It's been parked since.

I'm planning on pulling the carb off tomorrow. Any help on what I should be looking for? Obviously something that should be closed is stuck open, but I'm not really sure where, or what I should be looking for.

Thanks for all your advice!!

Your float is out of adjustment. Your manual should have specs on what the float measurement should be. You normally measure while holding the carb at a 45 degree. The manual should tell you.

But most likely the float is stuck open so the little needle is staying open and allowing fuel to constantly flow into the bowl.

I'm not sure if it will work on your XR6, but it's worth a shot. Simply remove the seat and tank, then loosen the hose clamps that hold the carb in the rubber boots. At this point you should be able to rotate the carb so you can get to the top and/or bottom. I rotate mine towards the right side of the bike, then I can access the bowl from the left side of the bike.

It sounds like your floats are stuck. When fuel enters the bowl, the floats 'float' which closes off a valve and keeps anymore gas from entering (kinda like the 'float' in your toilet bowl.) After you burn off some gas, the floats drop and let more fuel in, then float back up and shut off the fuel flow again. If the bike ran fine before, the adjustment, float height, should be fine. It sounds like the linkage is in a bind, or a bit of trash is making it stick. If the float height does need adjustment, you usually do so by bending a little tab.

Long story short, you should be able to fix this by simply rotating the carb to the side so you can get to the bottom. Otherwise, to totally remove the carb, you will have to swing up the rear subframe and airbox to get the carb free, and that's a pain in the arse.

Good luck.

To free up my float I usually just hit (or tap rather hard) the bowl with a rubber mallet. If you are on the trail and something like this happens, then a rock will work pretty good.

I work on bikes and see this problem all of the time. 90% of the time a spec of dirt will have got under the float valve and is stopping it from seating, thus the fuel runs out of the overflow. You'll need to pull the carb out (it's not that hard) and you might as well remove all of the jets while you're at it and blow everything out with compressed air. pull the floats out and make sure the float valve is clean and blow out every hole in the carb and remove any crud from the bottom of the float bowl. When everything s back together check the float level with the carb turned cylinder head end facing straight up (turned 90 degrees) and measure the distance from the bottom of the carb body to the bottom of the floats. The measurement should be 14.5 mm.

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