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Discussion Starter #1
OK folks, so it's been a long while since I've needed to ask a question here.

So, did some searching, can't find my answer.

Just today, pulled the tank back apart and put in new fuel.
Starts up fine, runs as well as an MV should, however it won't go past 7k while accelerating on the road. All gears seem the same.
Seems to rev past 7k in N on the stand.

Sort of thinking it might be the pump?
I'm nearing 10k on the mileage, 2009 B4.
 

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If it was fine before you pulled the tank off I'd say you need to check you've put it all back together correctly. If the fuel lines are pinched or the orings on the connectors aren't right then you don't get enough fuel flowing.
 

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Could be a pinched external fuel line under the tank. Lift the tank and take a peek and set it back down carefully. Happened to me before.
 

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Restricted fuel flow somewhere....time for a new filter?
 
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Discussion Starter #5
The bike went into "limp mode" where you can go over 30 mph. Which I know doesnt exist but there isn't another term for it.
So this is why I took it all apart.
It hasn't been fine for a while and I finally went through the tank to investigate. Always runs fine on the stand but then as soon as I head out something happens.

No fuel lines are not pinched, double checked
Filter was recently replaced but not this past go around and was fine before today
Seems like I replace the filter every time I pull the tank.

Filter might be the cheapest thing to investigate but I'm getting tired of pulling the tank to find nothing and have the same issue with a new filter. This is the third time it done this now.

I'm going to look into getting a new pump and see what that effect has.
 

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KingKole02;
Only thing left is the fuel pressure regulator......never heard
of one failing.....but that doesn't mean it can't happen
I need to make a simple plug in adaptor so I can test them
while mounted in the fuel pump plate
 

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@KingKole02: This sounds very similar to an issue I had with an '07 F4 312R. The bike would run for about 28 miles and then stumble and eventually die.

The problem was eventually determined to be poor connection at the fuel pump plate connectors. I had a mis matched set. Replacing those connectors and ensuring proper connection solved the issue.
 

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As Noel has said, pumps rarely fail, pressure regulators rarely fail. This sounds like fuel line connections...which do fail.
 
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Discussion Starter #9
The knurl and silent service, these are the kind of suggestions I’m looking for.
I’ve been over the fuel lines a hundred times, changed filters 3 times and it continues to exist.
However I’ve never considered looking more at these areas mentioned.
Persay I buy a whole new “used” assembly and swap it and it still exists then I look into the fuel rail as the whole pump plate assembly will have been eliminated as a problem.

however before doing that I will look over the pressure reg and the electrical connections.
I will say my level gauge doesn’t work as I’ve run out of fuel while testing and had to walk the bike home in the neighborhood
 

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The fuel rail is an open pipe. Problems on that end would be injector related.
 
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Discussion Starter #11
The fuel rail is an open pipe. Problems on that end would be injector related.
Okay, then injectors would be my next step. In my past experience injectors are usually the last thing to check.
 

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You can have injectors cleaned and tested...relatively cheap, like $20~25.

If you can't find a service near you reach out to Race City Injectors in Mooresville NC....usually one day turn around.
 

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It's not injectors it's fuel flow......
Lines aren't pinched, new filter
What's left?
Fuel pressure regulator and the only thing that can go wrong
is the spring breaking, which will raise the fuel pressure
And the quick disconnects, which are known to fail
I'm with Chuck
 
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Is the fuel vent clogged or restricted?
Won't make a difference...the pump will vacuum the tank down to the point of implosion on metal tank bikes.
 
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