Any light duty grease would do the trick .

Thanks, probably go with the patroleum jelly as it is the easiest

I would just dab your finger in whatever oil you are trying to keep in or keep out, run same finger on sealing surface of crankshaft and lips of the seal, me personally I do not use any lubricant on the outer surface of the seal, if you are lubricating that area to make installation easier then you are also lubricating it to make it easier to pop back out, which you don't want.

GFrench trick of windex on the outside or I sometimes use blue loctite on the outside.

I can’t figure this one out. I changed the crank seal and it fouled a plug today while riding. It’s been a problem for the last year and I thought I had finally solved it. I have it premixed right for now so I know it’s for the right amount of oil… I guess it could maybe be oil left in there from the bad crank seal. 

Pic of fouled plug please, as it came out. Does it just need a good thrashing. Is the carb Oring not sealing making it run super rich--does it rev out fully. Was it a very cold plug like a 9 & easily oiled up. maybe i'd best read back n see what lead up to this. Those right side seals are pretty solid & reliable on the big motors, double lipped & sprung. Never had one leak but not doing miles on the road like you guys & just full song around the paddock.

Haha I haven’t put many miles on this one myself. I’ll get picture up when I have a chance! The carb o-ring as in the manifold o ring on the front there? It probably could use a new one of those but I thought if anything they would make it lean? Plug is an 8 

Okay here’s the best pictures I could get of the plug with this lighting right now. It’s not what I thought it was going to look like. Also maybe I got ahead of myself when I said fouled as it will start but it was acting like it was when it was fouling plugs. I rode it for a couple of miles and then the rpms drop and won’t come back up untill it dies and then very hard to start after if at all. On initial startup with new plug it starts well and runs strong although I feel it should be zippier than it is but could need top end. 

How much have you ridden it since you changed the crank seal? Mine smoked quite a bit for a while after I changed the seals, it was burning out trans oil left in the crankcase. Eventually it all stopped, and now I only get a little bit of smoke when it's cold, then hardly any after it's warmed up.

I changed it yesterday and probably only rode 5 miles before the issue started again. I expected smoke but not this to hapoen