I recently bought a 2011 750 axi. I was having problems with it accelerating like it should. I put a new fuel pump in it with the filter to find out the new fuel pump was junk. So i put old fuel pump back in with a new filter as the old one was plugged up. It starts up and idles now but from and idle to a certain rpm you have to feather the throttle to keep it going then as the rpms get higher it runs good. Any ideas what i should check? I also added a ground wire from the battery to the frame. Thanks in advance!

 

That range of King Quads are prone to getting dirt in the injector filter. If you start getting running problems, this is the first thing to check, the filter screen is in the injector inlet, it can't be removed, but can be poked clean carefully with a tiny screwdriver, then blown out with compressed air. If that doesn't cure it, check the pump pressure, should be over 40psi. Not sure if the TPS is adjustable on the 750, it was on the 700 but not on 450/500s, this doesn't usually need altering anyway, but if all else fails ---.

 

Well I tried cleaning the injector. Made a little difference. But still isn't right. Trying to come up with a fuel pressure tester to test the fuel pressure. Could it be that some of the plugs under the plastic in the front being corroded and not making good contact and cause that too?

 

The wires from the handlebars have plugs under the front, so I guess a bad connection there could give trouble. Are you getting the FI light coming on when running?

 

Nope.

 

Just one point, you haven't mentioned the spark plug. I can't count the number of times rough running has turned out to be a faulty plug.

 

Well I put a new spark plug in it and it hasn't changed anything either. I took it for a ride and all it wants to do is backfire through the exhaust and intake and hardly go at a slow speed. At a loss now. Any more ideas? I am done spending money on it so it might be going down the road

 

Afraid not. Check the voltage across the battery with the engine running. Over 15v and the regulator is shot. I did have one that seized a cam due to the owner running it out of oil. It had freed off, but didn't run. Also had a 500 that sheared the flywheel key and put the ignition timing out.

 

It runs great once you get it up from an idle. It just stumbles and tries dying from an idle up a little bit in rpms. I just don't understand why it only does it from an idle up and then just quits and runs great. I wish I could send you a video so you could see and hear it and you would have a better understanding of what I am dealing with.