I have oil leaking from the plate where the oil filter goes.  It's leaking quite a bit and making a huge mess.  This began after I changed the oil (and oil filter) to Shell Rotella with the hope of stopping my sprag clutch from slipping (the Rotella, along with avoiding shorter rides, seems to have cured that problem).

When I changed my oil and filter I did use a new rubber gasket on the filter cover plate.  I think that it was fully embedded in the cover and do not think that I pinched it. 

Before I change the oil again and put in a new gasket, anyone have any ideas about what I might have done wrong or tips to prevent future leakage?  I've never had any leak there before.  TIA!

Been there, done that, got really hacked off with it. One simple thing to check (and sorry, but you need to get the filter plate off again); ensure that the mating surfaces are scrupulously clean.  If you're absolutely sure of that (and I was), I ran a thin smear of the devil's goo (AKA silicon gasket cement) around the filter plate on the area outside of the sealing ring. That stopped it without any worry of getting gasket cement inside the oil sump.

I never did find a definitive reason why but I suspect a slight warpage of the filter cover. It's only thin cast ally.

Thanks Dai. Good advice. It's always possible I warped the cover by overtightening one of the bolts last time I reinstalled it. Will try giving it a good clean and using some silicone.

I had a similar problem. After checking the o ring and that the surfaces were clean, it still dripped. I used a small amount of hondabond, which should be safe in that envirinment.

had a similar apparent issue

turned out to be not the oil seal ...but the screws holding the oil filter plate

I had installed some cheapo screws that hold the plate n place ...after a bit of observation I found that the thread pitch was correct ...but the thread thickness - depth was wanting ....replacement screws were obtained ..and without any silicon or resurfacing involved at all ..the issue disappeared

food for thought at a minimum

good luck

While you're at it be careful not to overtighten the cover plate screws. DAMHIK