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Hi all,
I'm just wondering about bikes these days... If a bike has a fuel pump, does that automatically mean that it has a fuel injected system?
I always thought that a carbeurated bike is gravity fed and therefore wouldn't require a fuel pump.
A friend of mine said that in the newer carbeurated bikes, the fuel pump serves more as a fuel pressure regulator than an actual pump.
Does anyone have a solid answer as to why a bike with carbs has a fuel pump?
Thanks for the feedback.

Chris
 

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Retired twice: Navy and as a govt contractor
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My 07 RSTD has a fuel pump and 4 carbs. Fuel pump brings up fuel pressure when you first turn on the key and then maintains that pressure as you ride. Now I have been told that you can (in an emergency) bypass the fuel pump and gravity will provide enough fuel to get you home if that pump fails.
 

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Lots of carburetor equipped bikes have fuel pumps. They help to insure a consistent and steady flow of fuel to the carburetor(s) which can be especially important depending on where the fuel petcock is, and where and how the carburetors are mounted.

Generally speaking, fuel pumps on EFI bikes operate at higher pressures and maintain constant pressure to the fuel rail, while fuel pumps for normally aspirated bikes operate at a lower pressure and fill the float bowls, rather then keep any constant pressures up in the fuel lines.
 

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Sometimes the bike has the fuel tank lower than the carbs. The 1983 Honda Magna is an example of this. To look at one, you would never realize it, but the upper tank empties into the lower tank which has the fuel pump.
 
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