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XR70 Fuel Overflow

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I just purchased a barely used 03 XR70R for my two boys.  The bike had sat for a very long time so I purchased a rebuild kit and overhauled the carb.  Did a full teardown, 5 cycles through the ultrasonic cleaner, and rebuild.  The problem I am having is the bike continues to leak fuel from the overflow tube on the bowl.  I have tried the following without any real improvement:

1.  Swap out the float needle with the original

2.  Bend the plastic tab on the original float

3.  Replace the float with a metal equivalant

4.  Bend that tab so it closes the needle valve sooner

5.  Polish the needle seat with a cut off qtip on my drill

I read somewhere that the main jet needle can cause this symptom but don't see how that is possible.  I have WAY too much time into it now and unless someone can enlighten me I might just replace the whole carb.  I see they have many on ebay.  The aftermarket ones are very cheap but an OEM looks like it would be $100.  Typically you get what you pay for but I wonder if anyone has had good success with the aftermarkets.


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The vast majority on EBay are larger carbs that will require a slip on air filter and additional tuning, assuming they are good enough quality to tune. If a larger aftermarket carb is what you want would be better off buying a 20mm from TBolt USA for a free dollars more.
If not, Motosport has stock carbs for $103.87 with free shipping.

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It won't leak fuel IF the float level is set correctly and the seat is seating (stopping the flow of fuel).
Easy to check, carb in your hand, float bowl off, fuel line hooked up.
Turn on the fuel, let the float down and up , see if the flow stops.
If it does the seat is working but the float isn't floating up to shut off the flow.
I'd say we've bought at least 50 small Hondas with "bad carburetors" only to bring in the shop and adjust the float level.
Some times the guy has bought a new carb - off eBay - he throws in the old carb, we fix the float level and we're good to go.
We've got a box of eBay carbs.

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