my 2000 650 keeps cutting out at wide open. feels smooth until rpms get high and then it starts to fall on its face. sad when a 350 rapter is out running you lol. I changed the plugs and it did not help. any suggestions? i cleaned the carb out before all this started. took jets out one at a time and cleaned them. checked the diaphram and its in good shape so im lost. want to go ride tomorrow but wont if i can fix this issue. thanks for the help

 

I think 2000's had the lowest rev limiter of all year DS's. Are you sure you're not hitting the limit? That's tripped up allot of people, especially after a tire or gear change, even exhaust.
Next, I would consider the diaphragm but you've checked that.
The petcock under the tank has filters on it inside the tank, might check there next. A few others are poor ground, crusty fuses under the seat or bad or weak battery. Possibly the charging system.
You say you cleaned the carb before noticing this so I'm wondering if that caused it somehow. Did you change the main jet or move the needle up or down? Did you alter the float level? Take a piece of clear hose and connect it to the carb bowl drain. Now bend the hose up higher than the carb and open the drain. The fuel level should be right about at the carb-bowl junction. Is your choke sticking? Are you sure you got the diaphragm top seated in the groove?
Good Luck

 

i have a ron woods cdi on my ds so the rev limiter should not be an issue. ill check a few things and see what happens

 

The DS has a breather hose that starts by the fuel cap and wraps around the gas tank a few times before exiting along side of the radiator.
If the hose gets pinched, it will lean out the fuel at top end.

OMR

 

and the air tube from the carb to the air box, the old models had flimsy ones and they will collapse at high rpm's

 

Might just need a little Sea Foam run though it.

 

may have figured it out. i have a pre filter on my k&n and it was pritty dirty so i removed it and tried a few runs and it did not stumble at all. gonna take it out to the trails tomorrow and see how she does. maybe all the grime was not letting in enough air at wot