Vintage Dirt Bike Q & A

Hey there! This MT 125 we just got runs fine, but it sat in the barn for a few months without running; the last time I started it up the carburetor leaked gas like crazy, seems like it came from the bowl. I think I remember that it was coming from the tube that is connected to the bottom of the bowl, it only leaks when the engine is stopped and the gas valve is open, gas does not flow from that tube when engine is running.

Anyone ever had that trouble? I'm guessing that it means the float is stuck down, but I have not wrestled the bowl off the carb as the clearances are tight and I worry about having to find a gasket if needed. So what is that tube for, the one that comes out of the bottom of the carburetor bowl? The repair book I have shows that tube on the bowl for every model, MR, CR, and MT. It looks like it is just a drain.

Would love to hear your answers.

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Got this old Honda Elsinore, a 1976 MT 125, that runs good but has a problem here or there, I hope to benefit from your experience...

Sounds like the float is stuck or the needle valve is stuck or 0-ring on needle valve seat is leaking or just plain ole crud preventing the valve from seating.

easiest way is to take the intake manifold off with the carb.

you can get gasket kits off e-bay for the carb.

OK, thanks. I'll give it a try as soon as I get the chance.

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Got this old Honda Elsinore, a 1976 MT 125, that runs good but has a problem here or there, I hope to benefit from your experience...

Your problem may be cracked stand pipe inside your float chamber, I had this on my mt250, it was a very fine hairline crack going along the side of pipe which I repaired by soldering after cleaning. I think it was caused by water trapped inside pipe then freezing. Make sure that your carb is drained and dry when storing in cold locations or you will pay.

OK Chinooka, freezing is a potential problem, that's for sure. Thanks for your comment. Best regards, Steve

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Got this old Honda Elsinore, a 1976 MT 125, that runs good but has a problem here or there, I hope to benefit from your experience...

I also had a cracked stand pipe. I bought a piece of copper tubing to fit at a hobby store and replaced it.