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Hi - I'm brand new - first post! So far I've leaned a lot by just reading. I inherited a 1995 900 SS from my father in law RIP. He was a great guy, great flat track racer and had a small collection of bikes. The 900 had always been maintained, and the carbs had recently been rebuilt, new plug wires, caps (the plugs were a mess and I changed them). The bike would crank but it would not start. I drained gas and put in VP 98 and got it to start firing on full choke. After it cleaned out it was running pretty good, occasional mis fire and "popping" a bit but both cylinders were firing so everything was going in the right direction. I was going to ride it this AM but it's raining. What I didn't notice at first is that the fuel pump is not running when I turn the key on. I checked the fuse and it's good. The wiring under the tank looks ok but I don't have a multi meter. My question is; is the bike supposed to run (it won't idle - won't run below 1100 rpm) without the pump running? Choke is closed bike seems pretty crisp running on the stand, I've revved it up to about 5500 and try to feather it down, under 1100 rpm just dies. Is the pump hard to swap out? Anybody have a link of how to do it? Thanks!
 

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If the tank is full of fuel it will run until the fuel level reaches somewhere around 1/3 to 1/2 of a tank, then the fuel level ie pressure to feed the fuel to the carbs gets too low and it will then die
 

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If the tank is full of fuel it will run until the fuel level reaches somewhere around 1/3 to 1/2 of a tank, then the fuel level ie pressure to feed the fuel to the carbs gets too low and it will then die
Wow, I'd love to have an RD 400 Daytona Special! So, if I have more than a 1/2 tank the 900 SS should idle with or without the fuel pump?
 

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yes it should run with over 1/2 a tank
 

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The pump should run continuously with unnecessary fuel returned back to the tank. If you have more than approximately 1/2 tank of fuel the system will feed fuel with gravity only even if the pump is not running.
 

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if it won't idle, but will run otherwise i would expect the pilot jets are blocked. often worth just buying now ones rather than cleaning the originals.
 

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i once forgot to reconnect a pump after working on a bike. ran on the bench and road fine for me, customer got many km away and it finally died on the freeway in the pouring rain. he got some more fuel into it, but it didn't run well until he lifted the tank and plugged the pump back in.

if the pump has been running and the lines have fuel in them, it will siphon fuel up and around and out to the y piece in the hose with the pump off. but once it loses that it's done.
 
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