dying out in midrange after WOT!!

[redbarchetta]

Here is what is happening after running at WOT for a short period of time I let off throttle then hit it again and machine will bogg out and will actually die if I dont release throttle and push again!! I had jug renicked last year on clutch side and noticed the small compression port is plugged with nickasil, is that a factor for powervalves or not!! It seems to get worse as the machine warms up, any help would greatly be appreciated!!!

Here is what I have 04 mtcat 900 new crank and top end, gutted airbox slp pipe and silencer, boyesen reeds and jetted with 390 mains, needle clip center postition.

 

[kingkat1150]

bogging

Maybe your throttle safety switch? Unplug the harness to the swith and try it.

 

[Rixster]

Maybe a bit lean in the mid range and you are getting a lean bog.

 

[redbarchetta]

Maybe your throttle safety switch? Unplug the harness to the swith and try it.

My machine is a carb I think what you are referring to is a efi machine is that right?

 

[redbarchetta]

Maybe a bit lean in the mid range and you are getting a lean bog.

I'm really not sure about a lean bog as it will completely die out if I don't let off throttle, would a midrange lean spot cause that? Any ideas on the compression hole that enters the power valves rixster?

 

[Idcatman1]

The compression hole you are talking about is there only to make it easier to pull the rope to start, it has nothing to do with the power valves. The earlier 900 cylinders didn't have it. When I get cylinders replated I always plug the hole anyway, it gives you a couple lbs of compression increase.
Check to make sure your power valves are working. When you start the engine and give it a little throttle the servo should cycle once. If there is something not right it will cycle again, if it cycles three times it will not open the valves when running. It doesn't really sound to me like it is the valves but it is still worth checking.

 

[kingkat1150]

bogging

All cats came with a safety switch on the throttle. The switch cuts out when the throttle freezes up or sticks. It also acts up when your cable is out of adjustment or if the switch its self malfunctions. My switch went bad and it would try to kill the engine every time i let off the throttle.