if its blue then its burning oil so yes it could be piston ring/valve stem seal..take the dipstick out and have a look at the condition of the oil,this will tell you if there any water in it..(head gasket failure)if its clear,as in no white sludge/mayonaise,then take plugs out and a compression test is the next best thing to do as that will tell you if theres valve/piston damage.

lilallstarz wrote:Could it be be a piston ring or an valve stem seal problem? And I think it's blue smoke

Could be an awful lot of things.

How / when did this problem come about? Were there any issues with the bike prior to it happening? How many miles / km has the bike done?

How long have you had it / how well is it maintained and ridden.

Valve stem seals tend to get gradually worse over time.

Any odd noises / Rattles? Have you rode it since?