What bike are you riding? Did you say "differential"? So maybe BMW?
If you're riding an old dry clutch air head, then no worries about using Synthetic oil with friction modifiers (which ruin wet clutches on bikes so equipped).
So, this means you can use any high quality, name brand synthetic oil if you have a dry clutch BMW. Otherwise, use caution. Mobil One make several good synthetic oils WITHOUT friction modifiers. I've been using them for over 10 years and 100,000 miles on several bikes. All good. It's car oil, works perfectly in any bike. And yes, as said above, you can switch back and forth from Syn to NON syn oil no problem, mix and match as you please.
In Mexico you will see lots of US oil brands (Havoline, Penzoil, Quaker State, Castrol and more) It's ALL Pemex. (made in Mexico !!) ... it's relabeled Pemex (Mexico's only oil). The US companies sold licensing for the use of their label and logo ... but the oil is simply Mexico's Pemex ... which honestly is real crap.
Ever wonder why even fairly new cars in Mexico smoke? Crap oil. So, the American companies sell the label but not the secret formula and additive packages in their oil.
Mexican Pemex has none of the modern additives common in good US
and Euro brand Oil. Ask knowledgable local bikers about this ... they ALL know and use only made in USA oil.
Look for speciality bike or car shops, you may find "the real thing", that is, oil made in USA, France, UK, Germany or Italy.
ALL contain modern additives and are "real" synthetic oil.
You'll never, ever find AMSoil down there but ... maybe
Mobil One. (car oil ... which is one of the best!)
I was able to find made in USA Mobil One at Mexican Wal-Mart stores but it's a bit rare ... and costs more than Hecho en Mexico Mobil One, which is also for sale and like all the others, is just Pemex in a Mobil One bottle. So, check the label for where it's "hecho'd"
Good luck from the guy who installs new sprockets with a new chain!
Why in God's name would one continue to run a worn out Sprocket with 20K miles on it? It's $30 and my new chain is $150.
In certain circumstances you may have no choice, but given the choice ...new sprockets when possible please.
A worn sprocket will EAT UP a new chain in short order. So instead of 20K service life, you get 10K!
In reading ride reports the last 10 or 12 years, failed drive lines (either chain or sprockets or both) are the number one show stopper for amateur travelers.
They simply IGNORE their drive line. Seen this several times ... IN PERSON ...
and when pointed out to traveler ... they had no clue the trouble they were in. Pretty common.
You're lucky, you have a shaft drive bike ... and they never fail ... right?

Where is Touring Ted and Ta Rider when we need them?
