Honda guys say 10w30 but kinda seem like yahoos lol.i figured id get better advice here! I bought a big red 600 miles great shape etc.from nephew in law a nerd couldnt remember service or find manuals.so i tune up change oil.pretty much right away notice trans slips cold intermittent.so i get on some forums find out the 10w30 is wet clutch specific.i used high grade conventional duh! Anyway dont think any harm is done but im having trouble finding oil local that meets everything they say to use.aka 10w30 j a s o ma.everything local is 4t 10w40.on the forums (honda)overall problems with slipping if any weight used except 30.my question is i found lucas synthetic 5w30 j a s o ma and wonder what you guys think?i want to change oil and get going today as im cutting trees and the big red sure would be handy! But i dont want to do anything that would hurt it either!.soany input,tips,experience,advice greatly appreciated! Thank you! Lance.