I seem to be having the same or similar problem with my 2000 ds. i would like to talk to you if it is not a problem so i can seek some advice or tech help. Email address is ritab@frontiernet.net. phone numberis 304-898-6216. I have free long distance so i can call you if thhis is a problem thanks, John

 

I have a 2000 ds. It only had like 10 hrs when i bought it four months ago. Ran fine about a month ago it would backfire sometimes when you would rev it a little while putting around. Then it Started sputtering like you have the choke on when you fed it throttle. This would happen after you really opened it up for a long distance like a mile or so. I took it and had it serviced he said the valves had tightened up and not closing so he adjusted an dsaid everything was ok. I took it hame ran fine until i ran it through the mile straight away, then it started sputtering again. I found i had a tore diaphram I replaced it today. Ran better than ever for about an hour or so even winding it out. Then it done the backfire thing and started the fluttering/sputtering thing Please help thanks, John

 

I felt like I'd been called out or in trouble at school over the loud speaker" Brian, please report to the dean's office" and everybody goes Ooooooooo
Take a hammer like the guys on Orange County choppers and beat on that carb - lol
I have done everything except boil the carb. And I don't know what the hell that would do anyway. It has been completely taken apart and cleaned at least 50 times. New everything. Still no worky. I put a different carb on and it runs perfect.
I wish I had a magic cure, but I don't.
I know there are several out there on this forum who will part with a stock carb for under $100