Runs poorly at low revs.

Did you check for water in the spark plug cavity? Really, it kind of sounds like it could also be low speed carb jetting issues.
dan

what are your carb specifications.pilot,needle,main jet.
At what temperature you mostly ride in Degrees Celsius.

Maybe I can give you then some info.

greetings Mathieu

drop the needle two clips!

regards

taffy

we had a 2004 fs 650e today to repair a couple of items.one was while idling the bike it would seem to miss a beat every so often at randon.this occured at least every 60 seconds.once the bike even stalled.this occured after full warm up.the bike has about 45 hours of use.we did 4 things to the bike and it then behaved properly.dont know which item fixed it ,or even if it is fixed at all.first we dropped the float bowl and a small amount of debris was removed,then we richened carb mixture screw about 1/2 turn,then we replaced spark blug with iridium one and last we replaced stock spark plug cap with a ngk one that did not use the screw

on top of the spark plug.the plug cap that came on the bike seemed to fit somewhat loose on the spark plug.all is well at this time.dan.