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Fuel Drain - Newb Q

Ginger Ninja

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Hello All,

New to this forum and just bought an '81 750 to restore to semi Café Racer. It is in pretty good mechanical condition so far. My question is that if I don't shut the fuel valve, a good amount of fuel is coming out the drain onto the floor (none when bike is running). I've owned several bikes before but no Hondas and none this old, so my question is, is if this is normal? If not what could be the problem. The bike has been modded a little (some good, some not) any comments? As well, I'd like to put some exhaust wrap on, any advice?

Thanks in advance
 
I don't know anything about the later 750s, but a lot of the times carbs have a screw/valve in the bowls that allows to bowls to be drained. I always drain my carb bowls before putting the bike away for the winter. Maybe one of yours is still open.
 
I am having a similar problem with my 1971 Honda. I can give you a few hints regarding where to start. It may be leaking from the vent hose to the float bowl, if your carbs are similar to my older model. You might be able to trace the leak by identifying which vent hose is leaking and tracing it back to the carburetor that is causing the problem. If you don't have vent hoses on your float bowl like my older bike has, take off the air box and turn on the petcock to determine which carburetor is leaking. Your problem is probably ( not necessarily ) related to the needle valve to the float or with the float itself in one of the carbs.
 
Agreeing with Steve L, you most likely have a needle valve or float issue. Check your float hieght, its a common issue with carb overflow
 
I posted questions on this web site about a leak from a carburetor vent tube on my 1971 K1. Another owner posted that I should look for cracks in the brass vent tube in the float bowl. That turned out to be my problem. So, Dirt Digger would probably also recommend that once you determine which carburetor is leaking, that you inspect the brass vent tube. I needed a magnifying glass to see my crack.
 
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