I have a 2000 M2 and let it sit too long- bad gas, varnish. OK, so I rebuilt the carb and put in '88 needle jet and #45 slow jet and I drilled out the slide to .109". The main jet is #195. I also removed the plug and adjusted the idle mix screw 2-1/2 turns out, then 1-1/2 turns out.
In either case I could not get it to run with the enricher out or in for more than 30 seconds before it died. Replaced nearly everything and the slide moves as it should, the fuel line is not pinched and the tank vent was disconnected but it still dies after about 30 seconds. I thought ,vacuum leak but can't keep it running long enough to test-kind of doubt it though. New gas and all- I'm stumped- any ideas, similar experiences? I can't seem to throttle it much either, all though it will throttle but as any normal cold start would, maybe a little weaker. I need a carburetor genius-can't afford $500 dyno tune in SF Bay area.
I have Bub's Bad Dog pipes and one of those round, open side, cast aluminum air cleaners-fairly open. I've down loaded a pile of stuff- a beatch to read since everyone mixes terms.
Thanks folks.

It would have been better to just clean out the carb and get the bike running to check the plugs before making jetting changes. How do you know the carb needed the changes you made?

The float bowl could be running out of gas, check the needle valve and float level.

I do not have a lot of experience with CV carbs.

The #45 slow jet is probably a good choice; should run well with about 1,1/2 turns out on the pilot screw. There is a Sticky post in the IronHead section on setting the pilot screw. The procedure is exactly the same for your CV carb.

The 195 main is way too big. Go back to a 180. Then do some scientific testing. Run it down the road at high RPMs; release the throttle a very small amount - then twist the throttle a very small amount; repeat several times. If it accelerates when you release or bogs down then the main is incorrect.

It would have been better to just clean out the carb and get the bike running to check the plugs before making jetting changes. How do you know the carb needed the changes you made?

The float bowl could be running out of gas, check the needle valve and float level.

What he said plus you need to check whether or not fuel is even flowing fast enough to the carb keep the float bowl full. It sounds like it's running out of gas.

45 is a good slow jet and the 195 is stock in the 2000 M2 so it should run ok although further tuning down the road may indicate a slight variance from that. I'm also at sea level (east coast though) and run 45/195 in my 2000 M2. I have not drilled out the slide and my screw is @ 2.25 turns with a Forcewinder intake. The first thing that I would suspect is a blocked passage way in the carb. Use some carb cleaner to soak parts (no contact with rubber) and then gently blow it out. The buells also are famous for leaking intake seals which can cause many poor running issues. One way to check is when running, spray some WD40 or similar around the intake manifold (not directly in the intake). If they are leaking you will notice a change. Actually if I had the carb off, I would pull the intake and change the seals anyway. Dennis Kirk has replacement 'blue" seals that are reported to be very good however I have not tried them personally. If everything is clean and sealed it should run and allow you to fine tune. These are really basic bikes. For more Buell specific info try a google search for badweatherbikers and you will find lots of Buell friends and know how. Have fun!

What he said plus you need to check whether or not fuel is even flowing fast enough to the carb keep the float bowl full. It sounds like it's running out of gas.

+2 on that. Sounds like fuel starvation.

I am still plagued by essentially the same problems having tried numerous jets. I guess I'll have to do the intake rubbers- I have hard time getting those damn bolts- large gut.

Remove fuel petcock & check to see if the filter sock is plugged up with varnish from old gas, then make sure the vacuum petcock is working