I have an Issue with my 1999 750F4 its when it starts its not running well. When cold With choke it revs out over 4000rpm then if you roll choke to half it's either cutting out or throttle response is very poor like it's miss firing. It's running on all cylinders so I'm thinking it's fuel issue. If it gets up to temperature is sometimes still has issue with no choke. It will just not rev out cleanly and revs flutter then it stops, again as if it's struggling for fuel.

Has a dynojet power commander 3 fitted and was set up on dyno before I bought it. I was thinking of disconnecting this incase it's causing issue.

Any ideas or has anyone faced same problem?

Thanks

When is the last time the fuel pump plate was pulled and the hoses and filter serviced?

While you have the tank off to service the hoses and filter you should put some new plugs in her. NGK CR9EIX iridium are the way to go.

We call it a choke but it ain't a choke..It's a little cam that opens the throttle plates a touch to increase revs. The ecu controls the fueling.

So when you close the " choke" you are effectively closing the throttle plates to minimum and there is it seems, not enough fuel getting through..

EDIT or maybe your air filter is dirty and there isn't enough air getting through.

Bike needs to be in a good state of service to have a start point..It may already be !

Also check all the vacuum hoses are connected and not split.

Does it only do this "when cold"?

In other words, if you keep at it long enough that the bike gets up to normal operating temperature...does it run ok?

Hi All, thanks for all the advice. I'm pretty sure plugs and air filter are good as it's hardly done any mileage since service. But I'm gonna check all the points you have all suggested and I'll get back to you in a couple of weeks. Tnx again

Is the fuel pump plate a cleanable filter? When u say hoses do you mean clean out the fuel supply hoses?
I need to get myself a workshop manual to make it a bit easier to get around this fine machine.

When you undo the plate at the bottom of the tank, you'll see all the hoses, fuel pump and filter . The fuel filter is a replaceable Mahle filter.. KL 145. It's not cleanable.

Do a search and you'll find all the info you need as to how to do this as this ground has been covered a good few times.

We used to have manuals on here that you could download...

Joe

Manuals here: Team Double 3 Racing | MV Agusta

This image shows the emissions lines and arrangement inside the fuel tank:



This image shows the parts you need to check or replace on the fuel pump plate:



The hoses are specific material to be immersed in fuel. They are J30R10 spec high pressure fuel lines. The fuel filter is Mahle KL145. The fuel pump plate connections are CPC and the originals are plastic and can be fragile. (They can also be a source of fuel starvation if detritus is trapped there.)

When you are ready to do this, contact me and I can help you source parts as I have most of that in my garage for forum use.