The situation: Overnight, rust started coming out of a moulded tunnel in the piston housing of my bike. The housing is Aluminium - so it shouldn't rust! I didn't cover the bike yesterday and the afternoon storms gave it a good soaking. Just behind the tunnel is where the sparkplug threads into the front cylinder, so I think that this is the source of ferrious metal. On the VTR250, water can pool around the bottom of the sparkplug recess on the leading cyclinder, and there was water pooled there this morning. The plugs were last removed last October for a 18,000 km service at Peter Stevens. If water is getting down the thread, what is coming up? The engine has been a bit rough - missing on one cyclinder - on starting until properly warmed up - could this have been the source? Is the tunnel to cool the sparkplug? Anyway, anyone got any advice? Take it to Peter Stevens? Or remove the sparkplug, try to clean the rust out, grease and reseat the sparkplug, and try some extra grease on the sparkplug seat?