Not arguing, but if the following is true, then pulling the cover should lean out the mix and give more power, right?
"4. Jetting. ALL of the inline fours came rich from the factory. At sea level, we started with a 10 size less than what it came with. Here in Colorado, it's not unusual to drop a 30 size main jet. The jet needles are almost always set too high (except the 500/550, too low). The cutaways on the slides were close for sea level, too low for high altitude by about .030". My 750K2 runs at 20 less than stock for general cross-country touring."
(From "The Wisdom of Hondaman.")
http://forums.sohc4.net/index.php?topic=7401.0I did the exact same thing i replaced the filter and put it back together and it did the same thing so for the hell of it i took the filter out and ran it without just to see and she run freaking great but i didn't want to run without a filter ofcourse but luckily when i pulled the tank to check the petcock ( just to be sure) i saw that vaccum hose not connected.
All the carbs are tied into a T joint and one hose comes off that and goes back to the air box if your not sure you have em hooked up right i would really find out for sure and correct the problem, i asked hondaman what was happening so i could learn and he said basically with the hose not hooked up the engine was gulping gas at an uneven rate and starving each carb of it's share of gas. With the hose hooked up it made a nice smooth fuel delivery to all 4 carbs at high RPMs which was my problem.
I just read your problem and it was the exact same as what i had just gone though and thought i would bring it up to help. anyways after you figure out the right vaccum hose orientation and make sure they are hooked up right and your still experiencing the same issues i would suspect a cracked hose but just for fun see if that hose comes off the T joint and goes right back to the airbox is hooked up right and not cracked and ill bet that loose hose goes to the airbox.
The new filter helped a little, but the real fix was removing the filter cover.
I am not sure if I have all the hoses connected right. I seem to have one hose that comes out over the carbs but is not connected to the enging.
One of those things I need to check out some day. 
Lee
So the new filter fixed the problem or do you have to modify the cover now? the only reason iam asking is i just went through this exact senerio with my 82 after doing the top end over the winter and it ended up being the vaccum hose that attaches to the air box was knocked off and i missed it. ( just wondering if you have a vaccum leak on that hose or it's not attached like what happened to me.
Yes. I was leery of it at first, myself.
However, my bike's symptoms (intermittent lack of power above 60-65 mph) vanished as soon as I removed the cover. And that was after I installed a new air filter!
Lee
A bit late reporting, but it works! Bikey has run like a different bike since I removed the air-filter cover.
I still haven't gotten the adjustment cover off to fiddle with the clutch. Maybe I'll stop at the auto parts store today and see if they have something that will work on that big screw thing.
I also probably need to invest in a new clutch cable one of these days.
Lee
Oh sorry only part of your question I answered ......Yoda.
Basically you leave the stock air filter plastic door off and using the same screws with fairly wide washers attached to hold the air filter inside it's wee cave.
Don't ask me if it works, I haven't tried it yet. 
Just so we are on the same page, you have to take the airfilter cover off so it runs better?
