Top end jetting?

[Ginxd00]

I have a 440EX with the mods listed in my sig. I had a race today, and it was going to be a little sloppy. So I installed the air box lid for the protection. Before the race with a new plug I did a full throttle test and it seemed to be fine with the jetting it had. 165 main. Well during the race on some big steep, lomey uphills, if I didnt ride the bejesus out of the clutch it would fall on its face and I would have to feather the throttle to clean it up. That would indicate a rich condition correct?

[NacsMXer]

Sounds rich if it's cutting out on top like that.

[FasstMidnightZ]

Sounds rich, I notice you got a FCR41 but a 165 Main isn't that big.
Does it do the same thing with the air box lid off?

[Ginxd00]

Originally posted by FasstMidnightZ
Sounds rich, I notice you got a FCR41 but a 165 Main isn't that big.
Does it do the same thing with the air box lid off?
No it dosent, I have the head ported and also 1mm bigger intake valves, so its a pretty efficient head setup. It dosent like a big main in there with the vented lid on. I am going to go with a 160 and see how she does. I am guessing the test I did was in a flat field with not much load on the motor, but as soon as it got load on it I really could tell. It reminded me of my old 330R when it was fat on the main.