Motorcycle Repair: Honda 504, 1975, mail thanks, rusty tank

Question
Dear Rich;
Hi, Hope this mail finds U in best of health. I'm a real dummy when it comes to motor bike repairs. My motor bike very often spills fuel from below the carburetors, especially when I ride on it for some distance. I have got its carburetors repaired many times but the problem persists. I would like to ask U if this problem is repairable as in Islamabad U can't find spare parts of such bikes. There is a real real shortage of heavy bike mechanics in Islamabad. I had to load it every time on a truck to take it for repairs to another city. Please do reply to my e-mail. thanks
Best Regards
Dr. Haroon

Answer
Haroon, the problem is that the floats can't control how much fuel is going into the float bowls so the fuel is running out the overflow vents. The problem could be incorrectly set floats, worn out needles and seats or dirt in the fuel line coming from a rusty tank that's getting between the needles and seats.  

This isn't a hard problem to fix if someone is a little familiar with motorcycles.  If you were a little closer, I'd be happy to try and help you get it fixed.  It's only a couple hours of work.

Regards
Rich