05 LTZ 400/455 Jetting Issues

Hey All, just joined and love the forums. This is my first post, so take'r easy on me. I have tried searching but can't seem to find my exact issue. So here it goes...

Ride in CO at 5000 - 8000 feet. Picked up a 05 LTZ 400. The guy I bought it from installed an Ice Cube 455 big bore and high compression piston. Dynojet Stage 2 kit with air box lid removed. The quad would idle very rough and want to stall but seemed very clean otherwise. Trust me, couldn't pass up the deal.

Here's what I found before I started tinkering:

Valves were tight.

No air box lid, dirty K&N Filter and no pre-filter.

Carb settings: Dynojet Needle at Clip #2. Pilot Jet 47.5. Main jet 175. Fuel screw destroyed, I had to us an easy out.

Here's what I did up to this point (per the Dynojet stage 2 recommendations):

Valves are adjusted to Suz spec.

Air filter / Pre-filter clean

Current Carb settings: Dynojet Needle at Clip #2. Pilot Jet 30. Main Jet 155. Added a manual adj fuel screw about 2 1/2 turns out.

Quad idles better, but not great. Seems to rev high when cold, then want to stall when warm. Idle screw adjustments just don't seem to work. Fuel screw adjustments help, but haven't been able to get it right. When its sitting, it seems to rev out good. When I get on to ride, it stalls out about about 1/2 throttle and I get nothing at full throttle. Then it wants to stall out and die. While at the track testing, I did a quick change on the needle setting moving it to clip #3 but then it just wouldn't idle at all and it would just stall and die.

I've cleaned the carb, blown out all jets, and can't seem to figure out what the heck is going on. Slide moves up and down ok. I haven't been able to remove the carb completely from the bike as I can't seem to get the choke cable out. (Could use some advise on this) And didn't want to disassemble the throttle side at the track.

Forgot to add.... it has a Yosh RS3 exhaust with a spark arrestor/quiet core insert.

Any and all help / suggestions are appreciated!

Jetting issues are RESOLVED! Come to find out, the Pre-filter was causing all the issues after I removed/replaced the stock fuel mix screw. I removed the pre-filter, set the jetting to: 155 main, 22.5 pilot, Clip #2 on the DJ needle, Fuel screw is approx 2 turns out at 8,000 - 10,000 ft. I could have gone down to a 150 main, but I was tired of working on the bike in the 30 degree weather. I'll be looking for a filtered air box lid as we mostly trail ride. I will NOT be using a pre-filter any more.

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