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Carb cleaning--Getting away with liquid carb cleaner-Other Carb questions

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Honda_Dan:
I have a 76 CB750F. When I put on full choke I can get the bike to start almost immediately. It runs and revs for about a minute and the engine sounds good, but when when I  would normally start easing off the choke as the bike warms up, it dies. (it does this regardless of whether I ease off the choke.)

I bought some carb cleaner additiive, which I added to a couple gallons of new gas. Do you think that running this tank of gas through the bike willl help the carb problem or will it require taking off and indiviually cleaning the carbs. I'm trying to avoid that, as I have never done it before and have heard it is difficult, and I will likely have to retune the carbs after cleaning.

Any thoughts? If I do take off the carbs, do I need to soak them, or can I get away with spraying carb and choke all over them.


Dan

Harry:
Seems to me the problem is getting enough fuel to carbs, not carbs themselves. When engine dies, open gas tank, if you hear air sucking in you have a vacuum = blocked tank cap vent. If not check tank filter in petcock and fuel lines for blockage. D'you have an inline filter - replace this.

Honda_Dan:
Would it also work to try to drain the carbs immediately after the bike dies? Or would a fuel flow problem not necessarily mean that they are empty. What about measuriing how much fuel comes out of each carb?

What about blowing in the tank cap vent?

Also, how do not know if I have an inline filter? How do I check this? Would it be in the petcock somewhere? 


Really appreciate your help.


Dan

Honda_Dan:
Also, I don't think this bike has a tank cap vent. It looks like it has another hose coming out the back of the tank and this is how air circulates.

Danh

Harry:
You need to be sure the flow of fuel into the carbs is sufficient to replenish the consumption of fuel by the motor.

When bike "dies" do the described gas cap test to hear if a vacuum in the gas tank is the cause.

If ok, close petcock, open drain screws under each carb (after placing a bottle under the drain tubes) and empty carbs. Open petcock and confirm you have a decent flow of fuel from each carb.

You have now identified/eliminated fuel flow to the carbs as your problem.

Report back here, and someone will take you through the next step.

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