Let me premise this short story with another short story. My 1998 FXDL, 80"EVO has had a primary side leak since possible forever. I bought the bike from the original owner and the documents he gave me with it say its been leaking since 2004...at least. I took it to my local indy and had them do all inner prim. seals and main shaft seal. Still leaks...Iv owned the bike just over a year and put roughly 12K on it.

I took my first real ride on her today yesterday when I rode from Memphis to the gulf (360mi+-) and back the next day (today) I change my oil every 2500 to 3k like a religion. I had not checked the oil in it in probably 1000 mile when I left for my ride. When I got to the gulf I was a full QT. low..WTF It rode like a champ...better than ever infact...no noise or anything. I rode all over town and found some bike oil (not Harley) castol vtwin 20-50 I believe, and topped it back off. I just got home and have not checked it again yet.

**I do not run synthetic
** I usually have a quarter-size stain under the primary after longer rides. I the bike doesnt get fully warm it doesnt drip.
** bike doesnt smoke and if I hold my hand in front of the exhaust it doesnt blow any oil dots on it...just burns my hand.
**bike has 50k on it. new cambearing and lifter 3kish ago. everything looked good in rocker boxes and cam chest.


so where did it go. burnt off, leaked out at speed?

 

Look in the primary, if the bike truly isn't leaking or burning it then that's the only place left.
John