Hard starting and warm up

[kevdog]

I have a 2002 Katana 600 with a micron muffler, the previous owner installed it. My guess is the carbs are stock. When its cold out or if the bike hasn't been started recently its very difficult to start and it will idle poorly until its been running a while. Occassionaly now when I ride and stop at a stop light it will idle high, around 3000 rpms. Any ideas?

[woobie]

Do you know the bike's history?

Being a 6 year old bike I wonder did the previous owner follow the maintenance schedule?

Any idea if the carbs have ever been cleaned? Have they been sync lately?

[kevdog]

I doubt the carbs have been cleaned or synched, it had pretty low mileage when I bought it.

[woobie]

Try running a adding some seafoam to a few tanks of gas and see if that helps.