I've been running full synthetic in my 08 roadliner since 4K miles. Did the 600 mile service with Yamalube which is a blend, but synthetic since then with no problems. Couple guys on the Facebook group for these bikes are scaring everyone about synthetic in these particular engines. Saying it causes problems with the lifters and valves among other things. This just doesn't make any sense to me. I would think an air cooled big v twin would be an excellent application for full synthetic oil. Am I wrong? Does anyone have any experience with these bikes? The other guys are saying it's basically a ticking time bomb since I'm using syn.