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Hi all,

Before I go tearing my bike apart, I want to have a plan of action. My 2007 SV650S was sitting for about a year and only ridden a few times in that period. I recharged the battery and got her going again after changing the oil. As she was warming up, gas started pouring out of somewhere high up on the motor. Could be a cracked fuel line but she only leaks gas (and a lot of gas!) while running. I'm thinking it might be the fuel pump. Anyone have this happen to them? No gas leak while sitting, but pouring gas while the motor is running? Fuel pump? Thanks in advanced.
 

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With the Tank up and the engine cold place some toilet roll under the fuel lines(1 sheet thick) or around the them around them and under the fuel pump and the T-junction pipes between the Fuel bodies. Crank the engine and see if you can spot any part of the tissue darken.

My fuel pump is mechanical but I think yours is Electric but some of the same rules apply.

When the engine cranks a partial vacuum is created from the rear fuel body pipe and that pulls down a Diaphragm in the Petcock which is a valve that allows fuel to flow.

This then goes to the fuel pump. From the fuel pump it goes to the fuel bodies via a single shorter fuel pipe that splits via a plastic t-Junction.

Sometimes leaks only appear when the engine is running and there's a bit of pressure in the lines.
 
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With the Tank up and the engine cold place some toilet roll under the fuel lines(1 sheet thick) or around the them around them and under the fuel pump and the T-junction pipes between the Fuel bodies. Crank the engine and see if you can spot any part of the tissue darken.

My fuel pump is mechanical but I think yours is Electric but some of the same rules apply.

When the engine cranks a partial vacuum is created from the rear fuel body pipe and that pulls down a Diaphragm in the Petcock which is a valve that allows fuel to flow.

This then goes to the fuel pump. From the fuel pump it goes to the fuel bodies via a single shorter fuel pipe that splits via a plastic t-Junction.

Sometimes leaks only appear when the engine is running and there's a bit of pressure in the lines.
With an electric fuel pump there's quite a bit of pressure. Like 40psi. Much more than your carbureted bike needs or has.
 

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With an electric fuel pump there's quite a bit of pressure. Like 40psi. Much more than your carbureted bike needs or has.
Good to know. Thanks for the info :)

Is this because of the EFI system?
 

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Yes. It needs to be pressurized so when the injector opens, it sprays a fine mist rather than a stream.
Thanks again. I've only ever had,"Naturally Aspirated" I.C.E engines but have looked into the basic workings of EFI systems. Past 15 years it's been CV carbs :)

From what I understand the fuel bodies on EFI can be balanced the old fashioned way and Electronically depending on the system?

I know i'ts a bit of OT but Carb/Fuel body balance is paramount to great engine performance for me. I suffer from Industrial VWF(Vibration White Finger) so have to keep my Motorcycle/s vibration free for comfort and stop hand fatigue.
 

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It depends how sophisticated the system is. On a early 2gen SV with its rudimentary electronics, you adjust some things mechanically. But later SVs make a lot of adjustments on their own via electronics.
 
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