carb or timing? which way to turn!
Alright. Here we go! Bike is a 98 Honda foreman 450s (a beautiful faded yellow finish I may add!). The issue is as follows. Bike runs rough at idle. Very rich. Sounds like a lawn mower and blows black. I went in the carb and gave it a real good clean using compressed air and cleaner. Reinstalled it and had the same problem. My second thought was a sticking choke so I triple checked that and it seems to be seated and sealing as it should. I took off the small inspection plug on the right side and found two marks on the flywheel that line up with a mark on the case. At this point both valves are closed and I have proper valve clearance. I turned it over by hand and both valves seem to be opening and closing smoothly and completely. I took it for a ride and it seems to go pretty good cruising down the road and under load but anything slow it spits and sputters and takes some finesse to keep it running.i can see the vacuum secondary jumping a good bit at idle.if I hold it with my finger to keep it from jumping it smooths out and runs ok. All the Jets are the correct size. Needle jet is correct and set to spec. So do I focus on the carb or is it sounding like timing jumped a tooth. I got the bike like this. I hate to start ripping the front off only to find everything is fine. Thanks for any ideas you have.