Jetting Carb Tuning AF ratio Questions 4th Gen

Gordo is a 1995 Honda VFR750F, he has this kind of airbox w/ a uni foam filter:
[image: Posted Image]
And a TBR slip-on exhaust.

#130 Mains all around, #40 pilots all around, mixture screws unknown
(I'm assuming these are Factory Pro Jets:)
[image: Posted Image]
Front Plugs:
[image: Posted Image]
Rear Plugs:
[image: Posted Image]

The problem I'm having is when it is very hot, I will encounter bogging and extreme flat spots all over the place in the power band. Is my setup (de-snorkeled, drilled airbox, slipon, #130) a bit too lean for the rear two cylinders? Where should my next tuning step be?

First off, why the drilled airbox? That's not going to do much good for ya.

Second, I'm in the camp that you don't need to up the jets for just a slip on. #125 mains are stock. Try going back to those, or at least bump down to #128s.

Did you do a carb sync? Can you adjust the pilots and put them back to stock? How's the fuel filter and air fliter? It's a start.

Drilled airbox: how the bike came. Why is it not good?
I should mention this is a CA bike, but with all the modifications done it wouldn't be a far stretch to imagine it has 49 state cams. It is on my 2do list to check.
Carbs were synced professionally 1,991 miles ago, when the plugs were replaced. Pilot (or slow) jets are the stock #40, pilot screws (I call them mixture screws) I can't adjust because I don't have a tool to turn them. Fuel and air filter are clean.

I may try going down to #128 in the front since they seem to be a bit rich.

One more question, what does to sub air cleaner do? I seem to be missing it on my bike, the connection in the carb for it just vents to open air...

Might be part of the PAIR system.

Drilled airbox is pointless. Doesn't do anything except hurt the design and airflow.

Why would you think someone swapped the cams? I don't know if they are different or not off my memory.

I believe the secondary air filter is an emissions thing for a breather tube that vents out to atmosphere.  Mine was so dry it was turning to dust, so I took mine out.  Whats the heat range on your plugs?

Your pilot screw - would it only rotate 3/4 the way before hitting a stop?  I'm just trying to see if what I saw was the pilot screw.

NGK CR9EH-9

I have no pictures above of the pilot (what I call mixture) screw.
The pilot JET is the bottom left brass flat head drive piece.

The Sub-air filter is some kind of vent for the carb slides. I just cut a little piece of filter foam to fit.