2002 Ace Deluxe 750 wont rev without choke out 1/8"

[2002shadowacedeluxe]

I have a few questions and i need some new thoughts.

Symptoms, The bike will warm up fine with the choke on, it will rev fine with the choke on during warm up, once warmed up, shut the choke off, bike will idle fine, but when revved once, revs fine, try to rev it twice and it stalls, hold half throttle and it just sucks likes its not getting any fuel, and will not rev up. Open choke 1/8" and it will rev fine, no problems.
It was popping out the rear cylinder exhaust randomly, i didn't notice it doing this last night. Normally i would associate this with a valve issue, but the compression tests seemed fine. I haven't done a leak down test on the cylinders yet. This popping does go away when the choke is out 1/8"
The original motor had 120,000 miles on it, my friend bought another off ebay that has 22,000 miles on it as it was more economical than buying all the cam chain rebuild parts and installing them on a engine with 120,000 miles.

Here's what has been done
Ebay Motor, valve lash checked, 22000 miles. All within spec.
Ebay carbs, opened up all passages are clear.
diaphrams, not cracked.
New fuel filter
Plugs
Removed new carbs, replaced with old carbs, same issue.
Choke cables have no adjustment so i cant see that being a issue ?
Compression test both cylinders are within one another by 10 lbs.
Used mapp gas to check for carb leaks.
checked exhaust crush rings, no apparent leaks on new rings.
swapped coils.
ohmed pick up.
carbs synced.
removed fuel cap from tank its not air locking.
Both cylinders seem to be firing and it runs fine as long as the choke is applied some.

So i know i have forgotten other things i have checked or tried, perhaps im missing something obvious.

I can't see the air cleaner box being removed from the engine causing too lean of a condition. Perhaps i am wrong.
Is there any issues with the front breather that is coming off the carb's to the mount on the front head possibly causing a lean issue, i am grasping at straws here. It has been hooked up everytime.
I dont see the screen in the tank causing an issue as i had a seperate fuel supply hooked up and thought maybe it was the issue and it wasnt getting enough fuel, the bike ran okay before it was all torn down, so i am leaning towards the new parts and a lean condition.
The intake boots are in great shape, no dry rotting or cracking.

I am at a loss and would associate all of these problems with a lean condition somewhere but at this point in time im just not sure.

[Scrapdog2grand]

If you are running it with out the air box, it will not take throttle.
If anything while running without the airbox , hold our hand over it and restrict the air flow.

[ibwaki]

Originally Posted by Scrapdog2grand

If you are running it with out the air box, it will not take throttle.
If anything while running without the airbox , hold our hand over it and restrict the air flow.

What he said, you have to have the air cleaner in place or you will not run rite. Too much air and you will have no throttle it will just bogg down.

[2002shadowacedeluxe]

Originally Posted by ibwaki

What he said, you have to have the air cleaner in place or you will not run rite. Too much air and you will have no throttle it will just bogg down.

Im gonna go try it, perhaps this motor is just more temperamental than any other one ive ever worked on lol

[ibwaki]

Let us know how it turns out.

[justinmahn]

Not sure if you've done this, but have you set the idle pilot screws yet? The covers have to be drilled out, so it's not an obvious adjustment.

[2002shadowacedeluxe]

I have a slight air leak behind the air box, where it connects to the boot that goes to the intake ram, but it pretty much solved it, its still a slight lean condition, i will get the sticks back out and re sync it and reset the air idle screws, Thanks for all your help.
I forgot to mention the bike has basically straight pipes on it, like i said its not mine, it is a friends who got it for free from another friend kinda deal.
Thanks again, i will let ya know tomorrow how it all works out.

[edwardl]

Yeah removing the airbox is gonna cause a way way too lean condition. Get a filter on there and rejet those/that carb(s)!!

[2002shadowacedeluxe]

Originally Posted by edwardl

Yeah removing the airbox is gonna cause a way way too lean condition. Get a filter on there and rejet those/that carb(s)!!

Currently the carb's have 150s in them if my memory from last night serves me correct.