Not exactley sure but....

[short4stuff]

On my yamaha 225DR It seems that it sometimes smokes... And when it does that sometimes it lasts for about 5 mins and smokes like hell. I am not exactley sure how the valves work, but could it be that one of them stick and a bunch of oil gets into my cylinder and takes 5 mins before it burns off??? What other explanation can you come up with?

[yamaha200E]

well my ytm200E smokes everynow and then but not bad and every one tells me not to worry bout it till it gets real bad so i would do that sameif i was u but thats my oppinion u may figure it out i dont know. kyle

[YamaChuck]

My DR is starting to do the same thing. Hey 18 years old now, it should be time for at least a top end rebuild. My guess is that it is a valve sticking.