NC23 Fuel Gravity Feed?

[DK-Tandy]

what is the postive and negative's of this?
will it still run ok or will i need to get a new pump for the fuel?

can someone enlighten me on the situation please?

[tanuki]

are you saying you want to remove the fuel pump and have it gravity fed like a 30/35?

Personally I'm not so sure it would work, Honda fitted the fuel pump to the 23/29 for a reason I'm sure if they could have got away without doing so they would have.

and also you run the risk of filling your sump with petrol if your carbs are not set up and pristine or if you are just unlucky and get a sticky float.....this would obviously only happen if you forgot to turn your fuel tap off everytime you stop.

Pros.....cant think of any, unless you want to save the 800 grams a fuel pump weighs....

[DK-Tandy]

Ooh ok, thanks, my fuel will go through to the carbs via the pump, but won't start, where as if it's gravity fed, the bike will start ? I will try linking back to my pump to see if it will start :)

[amorti]

are you saying you want to remove the fuel pump and have it gravity fed like a 30/35?

Personally I'm not so sure it would work, Honda fitted the fuel pump to the 23/29 for a reason I'm sure if they could have got away without doing so they would have.

and also you run the risk of filling your sump with petrol if your carbs are not set up and pristine or if you are just unlucky and get a sticky float.....this would obviously only happen if you forgot to turn your fuel tap off everytime you stop.

Pros.....cant think of any, unless you want to save the 800 grams a fuel pump weighs....

you'd have thought so, but they fitted one to first gen fireblades and deleted it on later models

I think the difference is that the fuel tap on the 400 is lower than the carbs so although it'd work, it would only work until the fuel level got to a particular height!

Definitely a valid point about the fuel draining through the carbs. All it'd take would be a sticky float. Most bikes without a fuel pump will have a vacuum operated tap to protect against that failure.

[DK-Tandy]

im still struggling to see how when the pump is conencted it will still move the fuel towards the carb (through the pipes etc) but wont start the bike? whereas without the pump, the bike will start?

[Matchlessman]

Have you checked the pump is working?

You can test it by connecting it directly to the battery. if you have the pipe off that goes to the carbs you should get a nice squirt of petrol out of it. (obviously make sure you arent smoking etc when you do this)

The pump doesnt seem to do much untill the bike is running, you should be able to feel it pulse once the bikes started, it pulses more frequently with higher revs.

[DK-Tandy]

well i presume the pump is working because once i fitted the restricters, i forgot to connect the pipe from the pump to the carbs and when i pressed the starter motor, fuel pissed everywhere..

once i connected the pipe up, it struggled to start, it finally started and sound ok, once i turned the bike off and tried again, the bike wouldnt fire untill i tried the bike with gravity fed fuel to which it started..

[amorti]

Check your battery voltage

[DK-Tandy]

if the voltage was low, wouldnt the headlights not be bright when ignition is on?

[amorti]

if the voltage was low, wouldnt the headlights not be bright when ignition is on?

Probably. But that's the first you've mentioned about headlights, we can't guess