Wom I read on the KLR650 forum (Tried-and-true engine and fuel fixes sub-forum) that these sorts of minor problems can be expensive to fix if done by the dealer. However, rather than asking your dealer to fix it - no dealer should be allowed near a KLR650 apparently - just use the bottom (not lid) from a 425g can of tuna. Gently tap it into place with half a house brick using another can as a drift. You will need to use some electrical tape to thicken up the gasket. The repair will still cost nearly $4 for the parts if you buy new cans unfortunately.