I bought a Royal Enfield Himalayan two months ago and did the first oil change at 274 miles. The bike calls for a 15w50 oil. I bought some Motul 5100 15w50 for $12.99 a liter. I saw Advance Auto near me stocks the Shell Advance Ultra 4T for $12.99 a quart. It seems to be a pretty good price for a full synthetic. The price of the Motul 7100 is $6.00 more a liter over the Shell. Is the Motul 7100 worth the higher price over the Shell or Motul 5100 at $12.99 a quart/liter?